Finally!
I don't think it's going to hang around, though, unfortunately, but boy was it fun last night. I wasn't the only one, either - every other car I saw was going sideways, including one older E-class Mercedes round by the town hall, on the cobbles. The tracks on the road made it very clear that pretty much everyone was planting too much pedal!
Muchos excellentes ;-)
29/11/2011
27/11/2011
more A2 suspension stuff
A rewrite of a post talking about FSDs and suspension in general on the Audi A2, and an extension to the post here.
My FSDs are just over two years old and have rolled 30 thousand kms in that time. Bought via Larkspeed in the UK.
I'd argue that FSDs aren't stiff. Especially in combination with 15s. With 17s I found them fine, with light 15s and Eibachs fine. However, this was all with worn droplinks.
The car pitches and rolls to a certain extent and this was improved significantly by the swap to lighter summer wheels. I have a set of TD Pro Race 1s and another of Rial Milano. The Uniroyal summer 195/50R15s were originally on the Rials and then moved to the Pro Race 1s. Difference? Significant - and there are two changes there: the rials are 6,5x15, TDs 7x15; and the weight. The Rials probably weigh 1kg more per wheel (though I don't have accurate numbers).
First thing I'd do, though, based on my recent experience, is change the droplinks to Meyle HD ones. Don't go original, they won't last. I'm on my fourth set, though I do drive a *lot* of gravel. They will tighten the ride up massively on their own.
The Nokian Hakka 7 in 185/60R15 on the Rials I have on right now have bedded in - as have the droplinks - and things are now more jiggly than they ever were with the summer tyres. Remember, though, that an awful lot of that *might* be attributable to the tyres, as they're winter ones and therefore have different properties by definition. Still, I drove the car several times with the new winters on and without the droplink change and it's seriously better now. But it also reports far more accurately what's going on at the front wheels - when there's no grip, that is telescoped through the wheel in a way that I've not seen in a while.
I will probably also play with the tyre pressures. I think they're at 2.5/2.7 front / rear at 10C. I'll probably drop it to 2.1/2.3 and see if that also improves the ride, which I expect it will.
I have a very strong feeling that the ride in the summer will be awful and that the droplinks will have made the difference. Then we'll end up on Bilstein B6s. FSDs also seem to be inconsistent between batches, so if you want the deliberate sportiness, don't do it and go B6 instead. Why the ride will be bad? Simple. Without preloading (i.e. a full car) the FSDs don't damp enough. They're pretty good when it's warm, but when it's cold they're like toffee. So you get the pitch and roll and nod and squat all the time when it's between +0 and +10 or so. For me that's not *too* much of a problem as we tend to drive long distances fully loaded and the rest of the time it's cold anyway.
Testing different suspension setups is one way to go, but remember that any one of those is affected by the wear and tear on different components. I seem to tear through droplinks and other rubber bushes, mainly because of the kms I drive on gravel.
There are a bunch of parts which make a huge difference and most people ignore them.
- Gearbox mounts
- Engine mounts
- Dogbone
- Wishbone mount rubbers
- ARB
I'll go through why: the system is set up based on the "aggregatenträger" or subframe. The frame is bolted to the car with I think it's 8 bolts.
On the left and right of that frame is a "konsole" which has the rear section of the wishbone attached with a large bolt. This is buffered against NVH ("noise, vibration, harshness") with a large rubber mount. That rubber degrades over time. Repeat on both sides.
The ARB is bolted to the "konsoles". The early car bars are mounted with plastic sheathes. Underneath these, the bar corrodes, splits the collars and then starts moving. There are no limits on the bar - say, a 3mm thick "collar" around the bar, as on the later versions - to movement. The "collar" stops lateral movement, of course. My ARB was moved by Stealth a couple of years ago and I moved it again myself last week. I want a new one with collars or it'll move again. Jubilee clips will not hold it in place.
The rubber bushes alone aren't enough, but they also tighten up the ride if they're replaced. Left-right movement is not supposed to happen - that's supposed to be stopped by the ARB - so if it's not tight enough, you get roll.
The ARB is connected to the suspension strut with the droplink. These get an awful lot of work and I'll agree with an opinion expressed on the German forum that they're undersized. Meyle now do HD ones - MAKE SURE YOU HAVE THE PERFECT TOOL TO BOLT THEM IN! The originals were relatively simple to bolt in but the meyle ones have a deliberately mis-sized nut (or Nyloc, I'm not sure and I haven't taken the others apart to see) so you absolutely must have something to turn the thread while you use a 16mm spanner to hold the nut. If it's even remotely the wrong size, you will break the rear section of the nut, meaning you need to get the flex out to remove it and replace it. I had to flex one of my old ones off and that's the first time that's been necessary.
The rear section of the subframe is connected to the gearbox with the dogbone. This also makes a signficant difference in NVH but less in handling.
Major other sources of NVH are worn engine mounts. The bolts *can* shear, so I'd suggest changing them if you're doing everything else, because you'll increase wear on the old parts.
The bottom of the suspension strut joins to the wishbone with a balljoint. On early cars - up to 2003 - the wishbone is cast iron and the ball is non-replaceable. The later cars have replaceable ones and wishbones made of steel pressings. So you can't replace this without the entire wishbone. If you're going to do both rubber mounts, then you could argue this would be a good idea.
The main thing, though, is that the car is essentially completely imbalanced. 75/25 front rear is slightly OTT but not very far off. This also means that any change you make at the front is disproportionately effective but also that most of the wear is at the front.
My FSDs are just over two years old and have rolled 30 thousand kms in that time. Bought via Larkspeed in the UK.
I'd argue that FSDs aren't stiff. Especially in combination with 15s. With 17s I found them fine, with light 15s and Eibachs fine. However, this was all with worn droplinks.
The car pitches and rolls to a certain extent and this was improved significantly by the swap to lighter summer wheels. I have a set of TD Pro Race 1s and another of Rial Milano. The Uniroyal summer 195/50R15s were originally on the Rials and then moved to the Pro Race 1s. Difference? Significant - and there are two changes there: the rials are 6,5x15, TDs 7x15; and the weight. The Rials probably weigh 1kg more per wheel (though I don't have accurate numbers).
First thing I'd do, though, based on my recent experience, is change the droplinks to Meyle HD ones. Don't go original, they won't last. I'm on my fourth set, though I do drive a *lot* of gravel. They will tighten the ride up massively on their own.
The Nokian Hakka 7 in 185/60R15 on the Rials I have on right now have bedded in - as have the droplinks - and things are now more jiggly than they ever were with the summer tyres. Remember, though, that an awful lot of that *might* be attributable to the tyres, as they're winter ones and therefore have different properties by definition. Still, I drove the car several times with the new winters on and without the droplink change and it's seriously better now. But it also reports far more accurately what's going on at the front wheels - when there's no grip, that is telescoped through the wheel in a way that I've not seen in a while.
I will probably also play with the tyre pressures. I think they're at 2.5/2.7 front / rear at 10C. I'll probably drop it to 2.1/2.3 and see if that also improves the ride, which I expect it will.
I have a very strong feeling that the ride in the summer will be awful and that the droplinks will have made the difference. Then we'll end up on Bilstein B6s. FSDs also seem to be inconsistent between batches, so if you want the deliberate sportiness, don't do it and go B6 instead. Why the ride will be bad? Simple. Without preloading (i.e. a full car) the FSDs don't damp enough. They're pretty good when it's warm, but when it's cold they're like toffee. So you get the pitch and roll and nod and squat all the time when it's between +0 and +10 or so. For me that's not *too* much of a problem as we tend to drive long distances fully loaded and the rest of the time it's cold anyway.
Testing different suspension setups is one way to go, but remember that any one of those is affected by the wear and tear on different components. I seem to tear through droplinks and other rubber bushes, mainly because of the kms I drive on gravel.
There are a bunch of parts which make a huge difference and most people ignore them.
- Gearbox mounts
- Engine mounts
- Dogbone
- Wishbone mount rubbers
- ARB
I'll go through why: the system is set up based on the "aggregatenträger" or subframe. The frame is bolted to the car with I think it's 8 bolts.
On the left and right of that frame is a "konsole" which has the rear section of the wishbone attached with a large bolt. This is buffered against NVH ("noise, vibration, harshness") with a large rubber mount. That rubber degrades over time. Repeat on both sides.
The ARB is bolted to the "konsoles". The early car bars are mounted with plastic sheathes. Underneath these, the bar corrodes, splits the collars and then starts moving. There are no limits on the bar - say, a 3mm thick "collar" around the bar, as on the later versions - to movement. The "collar" stops lateral movement, of course. My ARB was moved by Stealth a couple of years ago and I moved it again myself last week. I want a new one with collars or it'll move again. Jubilee clips will not hold it in place.
The rubber bushes alone aren't enough, but they also tighten up the ride if they're replaced. Left-right movement is not supposed to happen - that's supposed to be stopped by the ARB - so if it's not tight enough, you get roll.
The ARB is connected to the suspension strut with the droplink. These get an awful lot of work and I'll agree with an opinion expressed on the German forum that they're undersized. Meyle now do HD ones - MAKE SURE YOU HAVE THE PERFECT TOOL TO BOLT THEM IN! The originals were relatively simple to bolt in but the meyle ones have a deliberately mis-sized nut (or Nyloc, I'm not sure and I haven't taken the others apart to see) so you absolutely must have something to turn the thread while you use a 16mm spanner to hold the nut. If it's even remotely the wrong size, you will break the rear section of the nut, meaning you need to get the flex out to remove it and replace it. I had to flex one of my old ones off and that's the first time that's been necessary.
The rear section of the subframe is connected to the gearbox with the dogbone. This also makes a signficant difference in NVH but less in handling.
Major other sources of NVH are worn engine mounts. The bolts *can* shear, so I'd suggest changing them if you're doing everything else, because you'll increase wear on the old parts.
The bottom of the suspension strut joins to the wishbone with a balljoint. On early cars - up to 2003 - the wishbone is cast iron and the ball is non-replaceable. The later cars have replaceable ones and wishbones made of steel pressings. So you can't replace this without the entire wishbone. If you're going to do both rubber mounts, then you could argue this would be a good idea.
The main thing, though, is that the car is essentially completely imbalanced. 75/25 front rear is slightly OTT but not very far off. This also means that any change you make at the front is disproportionately effective but also that most of the wear is at the front.
23/11/2011
3ware 9650 red LED
go on, google will find it.
There isn't much on the web about this. One thing that has just occurred to me - I go the little blinking red LED on Saturday and figured the card was dead. One thing I haven't tried / checked is that the cache memory had been swapped out earlier. Since someone claimed this might be to do with the BBU, I figure it might also be to do with the cache... I'll take it out and test, but not right now.
PCI-X is supposed to be an extension of PCI, right? Well, I haven't managed to get the card to be accessed reliably in only a PCI slot. PCI-X is fine (if it's screwed down and only then) but PCI seems extremely unreliable.
Several different boards tested, all with similar results. 1TB and 1.5TB disks, Samsung, WD. Always the same - either they don't get identified every time or the don't get identified at all (the P5QL doesn't see anything, the P4SCI always sees them, the D945GCLF2 occasionally and the D510MO until they're in the same case). Go figure.
I think I'm going to be looking for a NF99-525 from Jetway with the extra ports on very, very soon.
- Bret
There isn't much on the web about this. One thing that has just occurred to me - I go the little blinking red LED on Saturday and figured the card was dead. One thing I haven't tried / checked is that the cache memory had been swapped out earlier. Since someone claimed this might be to do with the BBU, I figure it might also be to do with the cache... I'll take it out and test, but not right now.
PCI-X is supposed to be an extension of PCI, right? Well, I haven't managed to get the card to be accessed reliably in only a PCI slot. PCI-X is fine (if it's screwed down and only then) but PCI seems extremely unreliable.
Several different boards tested, all with similar results. 1TB and 1.5TB disks, Samsung, WD. Always the same - either they don't get identified every time or the don't get identified at all (the P5QL doesn't see anything, the P4SCI always sees them, the D945GCLF2 occasionally and the D510MO until they're in the same case). Go figure.
I think I'm going to be looking for a NF99-525 from Jetway with the extra ports on very, very soon.
- Bret
22/11/2011
"Don't tell anyone this, but it's..."
I heard this, this morning, followed by an explicit set of instructions how to spell the password in question. I'd got the username as well.
Couple of thoughts:
- You should not need to give users an admin password EVER. Give them an admin account local to the machine and then they are responsible for it.
- Don't assume that just because you're in a different country, someone won't understand your language.
- Admin passwords should not be simple enough to explain in terms of words (the password in question was laughably weak).
- If you need to administer lots of passwords, then use a password tool. Examples include password safe or keepass, both of which are cross-platform. Choose a decent passphrase!
- Bret
Couple of thoughts:
- You should not need to give users an admin password EVER. Give them an admin account local to the machine and then they are responsible for it.
- Don't assume that just because you're in a different country, someone won't understand your language.
- Admin passwords should not be simple enough to explain in terms of words (the password in question was laughably weak).
- If you need to administer lots of passwords, then use a password tool. Examples include password safe or keepass, both of which are cross-platform. Choose a decent passphrase!
- Bret
21/11/2011
the swimming pool
This was harder than I thought, and teh ISO levels are plain silly (ISO 4-8000) to get f5 and 1/500.
Anyway. Here a couple which I like despite / because of the noise...
- Bret
Anyway. Here a couple which I like despite / because of the noise...
- Bret
20/11/2011
server now sort-of running...
but without the RAID card - it appears to have died on me, which is a real pain. In the mean time I have 6 ports on the board, so I'll be using those.
I've hung three of the drives á la "Silentpcreview" in 5.25" slots with elastic. I am astounded by how much quieter they are.
Let's leave it at "those disks are the only ones in the server for the time being" and it's still louder than I'd like, though significantly more tolerable than it was.
Next up is to get some more memory and maybe a new case. Partitioning is causing a headache, too, as I could create a nice fast draft partition.... but since I've tended to work without too many backups, that would be a nightmare. So maybe slightly slower IO performance will still be acceptable. I'll have to test.
That's really the next set of steps: get the machine so far that I can put it where it's supposed to be going and let it run for a while.
- Bret
I've hung three of the drives á la "Silentpcreview" in 5.25" slots with elastic. I am astounded by how much quieter they are.
Let's leave it at "those disks are the only ones in the server for the time being" and it's still louder than I'd like, though significantly more tolerable than it was.
Next up is to get some more memory and maybe a new case. Partitioning is causing a headache, too, as I could create a nice fast draft partition.... but since I've tended to work without too many backups, that would be a nightmare. So maybe slightly slower IO performance will still be acceptable. I'll have to test.
That's really the next set of steps: get the machine so far that I can put it where it's supposed to be going and let it run for a while.
- Bret
17/11/2011
Servers, SAS, SATA and memory pricing
Since the server hasn't really got off the ground yet, I've found myself daydreaming about its replacement already. The hardware intended for it is kinda old (P4 3GHz and 'only' 4GB RAM) so I was looking... and was astonished to see that it would make all kinds of sense for me to scrap the DDR2 board I was looking at using and go straight to DDR3.
DDR2: €25 or so for 2GB and €45 for 4. DDR3? €20 for 4GB. Huh? That's pretty extreme.
Then again, the controller I'm using to get lots and lots of SATA ports - motherboards with more than six ports are rare - is a PCI-X one so to get the full value I'd need to replace that. Which then automatically means a new board and they tend to come with PCIe.. At least Intel and Supermicro have internal JBOD controllers with 8 ports in the €100 or so class.
Only fly in the ointment? None, really, except I find myself wanting an Intel S1200KP with 16GB and a PCIe x8 RAID card for 14 SATA ports. But that's also going to run a rather large amount of money. So, for the moment, the server's going to have to "make do" with 4GB. It is probably going to run Ubuntu as of now, as I want a Samba server running with its own domain. Might be a bad idea (may well be) but I don't want to run Win2k3 as I figure that will be even more resource intensive. Let's see. Performance isn't too important right now.
The HTPC board - P5QL Pro - will also get 8GB as and when, probably in two chunks. 6GB now and then later to 8, unless it also gets replaced (which I can't quite see, but hey). That case also needs building, and I will have to get on with that this weekend.
- Bret
DDR2: €25 or so for 2GB and €45 for 4. DDR3? €20 for 4GB. Huh? That's pretty extreme.
Then again, the controller I'm using to get lots and lots of SATA ports - motherboards with more than six ports are rare - is a PCI-X one so to get the full value I'd need to replace that. Which then automatically means a new board and they tend to come with PCIe.
Only fly in the ointment? None, really, except I find myself wanting an Intel S1200KP with 16GB and a PCIe x8 RAID card for 14 SATA ports. But that's also going to run a rather large amount of money. So, for the moment, the server's going to have to "make do" with 4GB. It is probably going to run Ubuntu as of now, as I want a Samba server running with its own domain. Might be a bad idea (may well be) but I don't want to run Win2k3 as I figure that will be even more resource intensive. Let's see. Performance isn't too important right now.
The HTPC board - P5QL Pro - will also get 8GB as and when, probably in two chunks. 6GB now and then later to 8, unless it also gets replaced (which I can't quite see, but hey). That case also needs building, and I will have to get on with that this weekend.
- Bret
Hard drive pricing...
following on from hard drive crisis - well, it looks like silly prices are back and hanging around.
I bagged 3 TB the day I saw prices going up, and I'm glad I did. A HD204UI is going at Reichelt for over €200 and that's been "coming down". Wow.
There was an article over at Tom's hardware (it's in German: link) about the situation and apparently the analysts claim it won't get any better until Q2 next year. I can understand that...
Bret
I bagged 3 TB the day I saw prices going up, and I'm glad I did. A HD204UI is going at Reichelt for over €200 and that's been "coming down". Wow.
There was an article over at Tom's hardware (it's in German: link) about the situation and apparently the analysts claim it won't get any better until Q2 next year. I can understand that...
Bret
16/11/2011
colorifying with GIMP and other PP stuff
I've been doing quite a bit of PP work lately, and today was no exception. Apart from that this was for work...
We have some clipart. We wanted the guy to have a different coloured shirt.
Right. After several completely false starts, I worked out the (a) way to do it.
- use the magic wand to select correctly, based on Saturation (not composite!) - though the white also worked well with all of the others.
- copy-paste the reserved section to another pic
- the stuff you want to colour: edge-detect
- convert to grayscale
- invert
- set the levels so you have mainly black / white / grey
- remove any imperfections (do it properly or it will show!)
- re-set the levels. I needed to return this lot to grey, because of the application (this is easy - move the bottom-left anchor point of the curve up the left axis - sorted)
- if you need to clean up again, do so
- now use colorify
- don't forget that colorify works as a glass filter, therefore it's over the top of what was there before. Since this is company stuff, the colours need to be right, so I was pasting the shirt as a new layer into the pic with the face - and then removing again after saving.
Don't forget that PNGs have transparency available, but if you're saving from a website, the transparency may not exist, leaving you with nice backgrounds you can't necessarily explain.
There's doubtless another way to deal with this stuff with another layer, and I'll probably try that next time I have to do something like this, but for the moment I'm reasonably happy.
The Color mixer did some interesting stuff, but it never really hit what I wanted. In an Ideal world, I'd probably actually convert the inside of the shirt to transparent to have consistent shirt outline colours, never mind what the internal one is. Since it's "only" for some PPTs, I'm not going to worry too much about that right now. It looks OK and I don't think we'll be using this stuff much.
I'm surprised, but the trick with edge-detect and grayscale and inversion was way more effective than I expected, so I'm happy.
Another thing I got hammered home over the weekend: use smudge with minimal opacity (say 10%) for minimal corrections. Another layer, of course, would do the same thing and allow you to change the opacity of the complete layer, but localized also works for certain things. cloning and using local colours is absolutely essential to cover up small imperfections (teeth spinach), as is working at pixel level. Even a single pixel shows up really well if it's the wrong colour.
- Bret
We have some clipart. We wanted the guy to have a different coloured shirt.
Right. After several completely false starts, I worked out the (a) way to do it.
- use the magic wand to select correctly, based on Saturation (not composite!) - though the white also worked well with all of the others.
- copy-paste the reserved section to another pic
- the stuff you want to colour: edge-detect
- convert to grayscale
- invert
- set the levels so you have mainly black / white / grey
- remove any imperfections (do it properly or it will show!)
- re-set the levels. I needed to return this lot to grey, because of the application (this is easy - move the bottom-left anchor point of the curve up the left axis - sorted)
- if you need to clean up again, do so
- now use colorify
- don't forget that colorify works as a glass filter, therefore it's over the top of what was there before. Since this is company stuff, the colours need to be right, so I was pasting the shirt as a new layer into the pic with the face - and then removing again after saving.
Don't forget that PNGs have transparency available, but if you're saving from a website, the transparency may not exist, leaving you with nice backgrounds you can't necessarily explain.
There's doubtless another way to deal with this stuff with another layer, and I'll probably try that next time I have to do something like this, but for the moment I'm reasonably happy.
The Color mixer did some interesting stuff, but it never really hit what I wanted. In an Ideal world, I'd probably actually convert the inside of the shirt to transparent to have consistent shirt outline colours, never mind what the internal one is. Since it's "only" for some PPTs, I'm not going to worry too much about that right now. It looks OK and I don't think we'll be using this stuff much.
I'm surprised, but the trick with edge-detect and grayscale and inversion was way more effective than I expected, so I'm happy.
Another thing I got hammered home over the weekend: use smudge with minimal opacity (say 10%) for minimal corrections. Another layer, of course, would do the same thing and allow you to change the opacity of the complete layer, but localized also works for certain things. cloning and using local colours is absolutely essential to cover up small imperfections (teeth spinach), as is working at pixel level. Even a single pixel shows up really well if it's the wrong colour.
- Bret
14/11/2011
security
Something very basic that a lot of us forget... don't use the same password for multiple online usernames, whether they're related or not.
It's relatively simple to find you, it's simple to find what forums you're on and if they're smart, they will use the initial password and ruin your reputation.
So:
- use complex passwords. I already linked to the cartoon, read it - use lots of words, the first and last or first two or last two and then maybe add a couple of numbers and / or punctuation. That's then easy to remember. The example I used yesterday was 'tree' 'cloud' 'sky' 'snow' - Te+cD-sy+sw-%128 is seriously complex but isn't *that* hard to remember.
- Alternative is to use a password safe of some variety - keepass springs to mind, as does "password safe" ;)
- make sure you have a password set on your computer at home and that that is different to each of your forum passwords.
- when you've changed a password, USE IT a few times to get it into your fingers. Don't change passwords - especially for example work ones - on a Friday! Do it Tuesday morning, when you get the opportunity to remember it and use it and you're awake enough to figure a decent password out.
I know, this becomes a lot of passwords. But that's the way it goes...
oh, and keeping your password safe on a service like dropbox is a very stupid idea.
- Bret
It's relatively simple to find you, it's simple to find what forums you're on and if they're smart, they will use the initial password and ruin your reputation.
So:
- use complex passwords. I already linked to the cartoon, read it - use lots of words, the first and last or first two or last two and then maybe add a couple of numbers and / or punctuation. That's then easy to remember. The example I used yesterday was 'tree' 'cloud' 'sky' 'snow' - Te+cD-sy+sw-%128 is seriously complex but isn't *that* hard to remember.
- Alternative is to use a password safe of some variety - keepass springs to mind, as does "password safe" ;)
- make sure you have a password set on your computer at home and that that is different to each of your forum passwords.
- when you've changed a password, USE IT a few times to get it into your fingers. Don't change passwords - especially for example work ones - on a Friday! Do it Tuesday morning, when you get the opportunity to remember it and use it and you're awake enough to figure a decent password out.
I know, this becomes a lot of passwords. But that's the way it goes...
oh, and keeping your password safe on a service like dropbox is a very stupid idea.
- Bret
13/11/2011
couple of proxy links
12/11/2011
some pics I've just found...
these are a couple of years old now, but I think they deserve an airing...
- Bret
- Bret
10/11/2011
that iframe thing - it was a hack
Bit more information on the iframe thing: it really is a hack / sploit (exploit). If you're using VBulletin 4, update ASAP to the latest releases please.
Bret
Bret
09/11/2011
security in your browser
Since I've just seen that one of the forums I use has an "interesting" iframe situation, I'll explain it in simple terms. I work in the security industry and write for work. So here a couple of tips and ideas about browser and browsing security:
- get yourself an up-to-date browser and keep it that way. That means running and accepting ALL updates. Knowingly so. Ninite.com provides apps to keep things up-to-date and they're rather good
- update *all* your applications, but especially the big ones. Adobe is on Reader X, Firefox is version 8 (yes, really) and Thunderbird? I can't remember but it's not 2. Update. Now. The same for Windows. Yes, there were six or so updates yesterday, it was Black Tuesday.
- Use something like ABP and NoScript. ABP - AdBlockPlus - kicks butt for removing scripts off of your page. Now it looks a bit like the iframe *may* have been an advert - or could be seen that way - but it gets stopped by the popup blocker. I'm not that bothered, I have my ABP stopping it, even if it's on a website / system I normally trust. ABP at least gives me the options of looking at things... NoScript is a pain to configure at the start, but that's the way it goes.
- Change your passwords regularly, and use complex ones, preferably using the first few or last few of a bunch of random words with some letters, numbers and punctutation thrown in. Read this - http://xkcd.com/936/ - for some background - but the concept is completely true. Password safes are to be recommended, but please use a real passphrase on the password safe and not just "mypasswords"...
- Defence in depth is the only way to go. Firewall on the outside, another one on the inside, software on the machines, AV updated regularly and preferably some kind of object reputation testing - is pretty damned essential if you're going to be messing - and the best bit is this: you are only ever as safe as the worst admin on all of the websites you surf. How good are they? Do you really, really know?
- Educate yourself on the important bits about computer security. What do your kids know? Where are they surfing? What are they trying to do? There was a great story on a forum about and 11-year-old who'd worked his way up from bikini girls to porn within a week. The only reason he'd been found out was through the browser history. Now, if dad didn't know how to deal with this stuff....
Get on top of at least the basics. Start now. Ask your kids for help if you need to, they'll enjoy the turnabout and it'll bring you closer together. You want something from me? Fine, ask! I will do what I can.
- The other nice bit is that the issue above might actually not have anything to do with the website, it could be a dodgy ad. You don't know and you can't prove it. It's not relevant anyway - wherever it came from, you don't want it and the best way around is to defend at all layers.
And keep a good, reliable, consistently updated backup or be prepared to lose all your data....When was the last time a hard disk of yours stopped working? Did you have a backup then?
- Bret
- get yourself an up-to-date browser and keep it that way. That means running and accepting ALL updates. Knowingly so. Ninite.com provides apps to keep things up-to-date and they're rather good
- update *all* your applications, but especially the big ones. Adobe is on Reader X, Firefox is version 8 (yes, really) and Thunderbird? I can't remember but it's not 2. Update. Now. The same for Windows. Yes, there were six or so updates yesterday, it was Black Tuesday.
- Use something like ABP and NoScript. ABP - AdBlockPlus - kicks butt for removing scripts off of your page. Now it looks a bit like the iframe *may* have been an advert - or could be seen that way - but it gets stopped by the popup blocker. I'm not that bothered, I have my ABP stopping it, even if it's on a website / system I normally trust. ABP at least gives me the options of looking at things... NoScript is a pain to configure at the start, but that's the way it goes.
- Change your passwords regularly, and use complex ones, preferably using the first few or last few of a bunch of random words with some letters, numbers and punctutation thrown in. Read this - http://xkcd.com/936/ - for some background - but the concept is completely true. Password safes are to be recommended, but please use a real passphrase on the password safe and not just "mypasswords"...
- Defence in depth is the only way to go. Firewall on the outside, another one on the inside, software on the machines, AV updated regularly and preferably some kind of object reputation testing - is pretty damned essential if you're going to be messing - and the best bit is this: you are only ever as safe as the worst admin on all of the websites you surf. How good are they? Do you really, really know?
- Educate yourself on the important bits about computer security. What do your kids know? Where are they surfing? What are they trying to do? There was a great story on a forum about and 11-year-old who'd worked his way up from bikini girls to porn within a week. The only reason he'd been found out was through the browser history. Now, if dad didn't know how to deal with this stuff....
Get on top of at least the basics. Start now. Ask your kids for help if you need to, they'll enjoy the turnabout and it'll bring you closer together. You want something from me? Fine, ask! I will do what I can.
- The other nice bit is that the issue above might actually not have anything to do with the website, it could be a dodgy ad. You don't know and you can't prove it. It's not relevant anyway - wherever it came from, you don't want it and the best way around is to defend at all layers.
And keep a good, reliable, consistently updated backup or be prepared to lose all your data....When was the last time a hard disk of yours stopped working? Did you have a backup then?
- Bret
Some Icetrack shots
I've just dug these out for a page, so I'll post 'em here as well. Click to make them larger!
- Bret
- Bret
08/11/2011
The "A2 common fault guide" in English
I'll help to update the German version of this later... in the mean time:
The petrol should sound like it's doing work; pickup should be clean from tickover and the red line is around 5200rpm. It won't zing all the way round, especially if it's wearing 17s, but it should be clean and pull strongly from 2500 and only fade off at 4800 or so.
If it's earlier, the airfilter is probably due for a change (which is a good idea anyway).
AUAs can have a software upgrade which is well worth it, it improves the way it hangs on the gas and makes it more drivable.
Drive over a small bump or two with some lock on the steering @ 15-20mph; there should be no "clongs" and if there are, you need the ARB or connecting rods looked at / replaced. It's no biggie, but still.
1.4s have no discs at the rear, so as long as the handbrake is pulling equally on both sides, no issue.
For the springs, I don't think you'll really notice it's about to break, but if it does it will make nice noises when you turn the wheel whilst standing still.
Other quick stuff to check:
- the left button on the instrument cluster - check when it thinks the next service is due
- kerbed alloys
- climate: put the fan on 3 or 4 bars and then try diverting the air around. If it has a problem pushing it (you should hear it, but do this while the engine's not running), there is a flap issue (many, many cars have this) and you should think about getting them to replace the central distribution unit as it's something you can do yourself but is a real ****.
Also try the demist button and then Auto. There should be no perceivable draughts once it's reached temperature and no real temp changes (it's a good system).
- drop the back seats, one at a time (move the front ones forward). Pull the handle behind the seat, let it drop. Now pull from the handle at the rear side of the base. When you've checked that the leg to hold it in place is fine and fits (!), drop the seat again. If it doesn't latch, lean on it with some weight and then you can raise the seat back itself back to the upright position.
- check the state of the b-pillar covering on the driver's side. If it's tatty, ask them to replace it. It's not expensive but does get some abuse from nice people who just let the seat belt go.
- put the lights on and check the glovebox light works.
- use the remote to open the boot (from several feet away) and try to shut it again after checking the state of the plastic in front of the door opening. Try also using the key to open and shut the windows: press and hold lock or unlock. If they don't work, reset the window (drop it to the bottom, hold for 2 sec, then raise completely and hold for 2sec) and repeat.
- check under the sills on the outside; there are many who do not understand the correct jacking points and therefore try to raise the car using the plastic sills. These do not take kindly to the treatment.
- take the bonnet off and check the rear corners for scratch damage. You can check the last brake fluid change and the state of the coolant at the same time. Fit the bonnet at the back first, then seat it and push backwards, then turn the locking knobs.
- headlamp levelling appears to be an issue for some
- the state of the inside trim (a-pillar) on the drivers side may be nasty, as it will be the place everyone rests their foot against. it's cheap to replace.
- if there's a cruise control: set it. It should work above 25mph or so. Try accelerating and decelerating.
- if they allow it or are prepared to do it, a VAG-COM readout will tell you more than you need to know.
- Bret
The petrol should sound like it's doing work; pickup should be clean from tickover and the red line is around 5200rpm. It won't zing all the way round, especially if it's wearing 17s, but it should be clean and pull strongly from 2500 and only fade off at 4800 or so.
If it's earlier, the airfilter is probably due for a change (which is a good idea anyway).
AUAs can have a software upgrade which is well worth it, it improves the way it hangs on the gas and makes it more drivable.
Drive over a small bump or two with some lock on the steering @ 15-20mph; there should be no "clongs" and if there are, you need the ARB or connecting rods looked at / replaced. It's no biggie, but still.
1.4s have no discs at the rear, so as long as the handbrake is pulling equally on both sides, no issue.
For the springs, I don't think you'll really notice it's about to break, but if it does it will make nice noises when you turn the wheel whilst standing still.
Other quick stuff to check:
- the left button on the instrument cluster - check when it thinks the next service is due
- kerbed alloys
- climate: put the fan on 3 or 4 bars and then try diverting the air around. If it has a problem pushing it (you should hear it, but do this while the engine's not running), there is a flap issue (many, many cars have this) and you should think about getting them to replace the central distribution unit as it's something you can do yourself but is a real ****.
Also try the demist button and then Auto. There should be no perceivable draughts once it's reached temperature and no real temp changes (it's a good system).
- drop the back seats, one at a time (move the front ones forward). Pull the handle behind the seat, let it drop. Now pull from the handle at the rear side of the base. When you've checked that the leg to hold it in place is fine and fits (!), drop the seat again. If it doesn't latch, lean on it with some weight and then you can raise the seat back itself back to the upright position.
- check the state of the b-pillar covering on the driver's side. If it's tatty, ask them to replace it. It's not expensive but does get some abuse from nice people who just let the seat belt go.
- put the lights on and check the glovebox light works.
- use the remote to open the boot (from several feet away) and try to shut it again after checking the state of the plastic in front of the door opening. Try also using the key to open and shut the windows: press and hold lock or unlock. If they don't work, reset the window (drop it to the bottom, hold for 2 sec, then raise completely and hold for 2sec) and repeat.
- check under the sills on the outside; there are many who do not understand the correct jacking points and therefore try to raise the car using the plastic sills. These do not take kindly to the treatment.
- take the bonnet off and check the rear corners for scratch damage. You can check the last brake fluid change and the state of the coolant at the same time. Fit the bonnet at the back first, then seat it and push backwards, then turn the locking knobs.
- headlamp levelling appears to be an issue for some
- the state of the inside trim (a-pillar) on the drivers side may be nasty, as it will be the place everyone rests their foot against. it's cheap to replace.
- if there's a cruise control: set it. It should work above 25mph or so. Try accelerating and decelerating.
- if they allow it or are prepared to do it, a VAG-COM readout will tell you more than you need to know.
- Bret
tip on A2 suspension
Various parts wear over time.
- Droplinks go "clunk" when the wheels are tyrned and are pushed up at low speed
- loose ARBs go "clunk" over bumps driven at straight-on. If the noise sounds like it's coming from the right, it's coming from the right.
- ARB bushes should be changed as a matter of course at 8 years old or so. Replace with Polo rubber bushes, tighten correctly *with the car on the floor*.
- the front mounts of the wishbones are in the "consoles" themselves and it's relatively easy to strip the threads of the main bolts in the consoles. So replace them if you have to - you can get the complete setup for €55 on Ebay. (or at least you could when I last looked). Symptoms of worn bushes include excessive tyre wear and wobble at higher speeds that is not consistent.
- if you change one side, change the other, too.
- droplink replacements include something from Meyer called a "HD droplink" (google for it using the German word, "Koppelstange"). The ends of the bars are significantly larger than the originals and should therefore hold longer.
- if you're replacing shocks, replace the seats and top mounts at the same time. There's no point not doing it.
- remember that quite a few components on the suspension actually have a limitation on how many times you should re-use the bolt, i.e. zero - so replace if for example, you replace the consoles or the wishbones.
- wobble under braking at low speeds MAY be caused by the track rod ends, it may be the discs are warped. I've swapped the ends and they were a cause of a lot of it, but my discs are still obviously not 100%. OTOH, they are 106tsd kms old, so I'm not complaining too loudly... still on the first pads, too.
- other sources of wobble include the mounts of the engine and gearbox, and possibly the driveshafts. There's not much you can do to specifically isolate one, though the rearmost gearbox mount - "Pendelstütze" - is relatively simple to replace with one from a polo at 1/3 of the price of the A2 one... It will also deal with some of the vibrations.
HtH.
- Bret
- Droplinks go "clunk" when the wheels are tyrned and are pushed up at low speed
- loose ARBs go "clunk" over bumps driven at straight-on. If the noise sounds like it's coming from the right, it's coming from the right.
- ARB bushes should be changed as a matter of course at 8 years old or so. Replace with Polo rubber bushes, tighten correctly *with the car on the floor*.
- the front mounts of the wishbones are in the "consoles" themselves and it's relatively easy to strip the threads of the main bolts in the consoles. So replace them if you have to - you can get the complete setup for €55 on Ebay. (or at least you could when I last looked). Symptoms of worn bushes include excessive tyre wear and wobble at higher speeds that is not consistent.
- if you change one side, change the other, too.
- droplink replacements include something from Meyer called a "HD droplink" (google for it using the German word, "Koppelstange"). The ends of the bars are significantly larger than the originals and should therefore hold longer.
- if you're replacing shocks, replace the seats and top mounts at the same time. There's no point not doing it.
- remember that quite a few components on the suspension actually have a limitation on how many times you should re-use the bolt, i.e. zero - so replace if for example, you replace the consoles or the wishbones.
- wobble under braking at low speeds MAY be caused by the track rod ends, it may be the discs are warped. I've swapped the ends and they were a cause of a lot of it, but my discs are still obviously not 100%. OTOH, they are 106tsd kms old, so I'm not complaining too loudly... still on the first pads, too.
- other sources of wobble include the mounts of the engine and gearbox, and possibly the driveshafts. There's not much you can do to specifically isolate one, though the rearmost gearbox mount - "Pendelstütze" - is relatively simple to replace with one from a polo at 1/3 of the price of the A2 one... It will also deal with some of the vibrations.
HtH.
- Bret
now with speed ;-)
Finally got the firewall machine up and running correctly - gigabit internally, though I need a new switch for that - and the rest seems pretty good.
Pain in the neck with password generation tools: I need to limit the special characters used, so that "?" isn't in there.... oh, and I don't like the idea of backslash in a linux password either :D
- Bret
Pain in the neck with password generation tools: I need to limit the special characters used, so that "?" isn't in there.... oh, and I don't like the idea of backslash in a linux password either :D
- Bret
a post on something completely different: A2 suspension
There are multiple options:
- FSDs are soft-ish
- Bilstein B4s are "standard", B6s a tick harder and B8s shorter
- Spidan springs are as "standard"
- Weitec springs are harder
- Eibach / ABT springs are a *tick* harder
Tyre pressures make a huge difference. I was running 2.3 all round on my car and then changed it to 2.7 or so at the back. The crashiness over potholes increased - and massively, too. I drive a set of gravel roads regularly to the stables and the holes don't change *that* much, so I know where they are - and the difference is amazing. I much prefer the 2.3 setup.
Wheel weights also make a huge difference, so lightweight wheels with low profile 15s, Spidans and FSDs are probably the softest / most effective "magic carpet" combo you will get. B6s will also be not far behind.
FSDs also seem to not be consistent between one batch and another.
From here:
- minimal roll, nod, squat is probably acheived with Koni Yellows, Oz Ultraleggeras in 17x7 with 205/40R17 and Weitec springs
- medium comfort with some roll, nod, and squat: Oz Superturismo, B6, Weitec or ABT / Eibach
- high comfort with some sportiness left: 195/50R15 on, say TD Pro Race, B6 or FSD, Eibach
- comfort: B4, Spidan, pepperpots with 185/60R15.
Do not forget to check the droplinks and the antirollbar mounts as if they are loose or worn, you will get crappy handling.
Addenda to this: I recently replaced the droplinks with Meyle HD ones and the difference is astounding. Much, much better.
Bret
- FSDs are soft-ish
- Bilstein B4s are "standard", B6s a tick harder and B8s shorter
- Spidan springs are as "standard"
- Weitec springs are harder
- Eibach / ABT springs are a *tick* harder
Tyre pressures make a huge difference. I was running 2.3 all round on my car and then changed it to 2.7 or so at the back. The crashiness over potholes increased - and massively, too. I drive a set of gravel roads regularly to the stables and the holes don't change *that* much, so I know where they are - and the difference is amazing. I much prefer the 2.3 setup.
Wheel weights also make a huge difference, so lightweight wheels with low profile 15s, Spidans and FSDs are probably the softest / most effective "magic carpet" combo you will get. B6s will also be not far behind.
FSDs also seem to not be consistent between one batch and another.
From here:
- minimal roll, nod, squat is probably acheived with Koni Yellows, Oz Ultraleggeras in 17x7 with 205/40R17 and Weitec springs
- medium comfort with some roll, nod, and squat: Oz Superturismo, B6, Weitec or ABT / Eibach
- high comfort with some sportiness left: 195/50R15 on, say TD Pro Race, B6 or FSD, Eibach
- comfort: B4, Spidan, pepperpots with 185/60R15.
Do not forget to check the droplinks and the antirollbar mounts as if they are loose or worn, you will get crappy handling.
Addenda to this: I recently replaced the droplinks with Meyle HD ones and the difference is astounding. Much, much better.
Bret
'droid and google accounts
I am astounded to note that essentially I cannot install apps on the work spare phone I have. Why? because there was already a gmail account associated with the phone. Get this: I cannot change the account without resetting the phone completely.
How stupid is this?
I can't even add the phone number and / or create a google account for it without running Market from the phone. So essentially there's no guarantee *anything* will work.
Compare and contrast to Maemo's debian-style catalogues.....
I will not be buying a 'droid phone.
- Bret
How stupid is this?
I can't even add the phone number and / or create a google account for it without running Market from the phone. So essentially there's no guarantee *anything* will work.
Compare and contrast to Maemo's debian-style catalogues.....
I will not be buying a 'droid phone.
- Bret
07/11/2011
I don't get it?
the machine booted. I thought I'd overwritten the IMG again on the USB stick - but all it took to get the pfSense to boot was to remove the CF Adapter. ACPI errors are now gone. WTF?
It's also now running from the USB stick happily. huh? I'll check if this is a suitable long-term solution and then leave it if it is.
- Bret
It's also now running from the USB stick happily. huh? I'll check if this is a suitable long-term solution and then leave it if it is.
- Bret
06/11/2011
ah, bollocks
... and the D201GLY2 WILL NOT BOOT FreeBSD!
I do not get this. We are writing 2011, yet I cannot get a "simple" OS to run on a several-years-old board. I've now spent I don't know how many hours on it and it still will not work....
Last chance: I've hooked up a spare 2.5" disk and am rewriting the image now. If it doesn't work, something else is coming in to take its place, I have had enough.
Win7 is heaven compared to this....
- Bret
I do not get this. We are writing 2011, yet I cannot get a "simple" OS to run on a several-years-old board. I've now spent I don't know how many hours on it and it still will not work....
Last chance: I've hooked up a spare 2.5" disk and am rewriting the image now. If it doesn't work, something else is coming in to take its place, I have had enough.
Win7 is heaven compared to this....
- Bret
interesting escapade with PhysDiskWrite and a USB Stick
A while back, there was an offer in Citymarket for 8GB SanDisk Micro USB Sticks for €10 each. I don't know if it's still a good deal, I'm not really bothered.
I picked up two - I've generally had good experience with Sandisk, so as they were cheap...
Now, today, I'm trying to use one as a boot device for FreeBSD. Fail. Epically. 9 times out of 10. Why? Good question, because if I swap to the other stick, physdiskwrite just goes through. Not particularly fast, mind, but it runs.
So the only thing I can think of is that there's a couple of corrupt locations on the stick and normally in Filesystem use, these won't cause any issue. Right now, though, because this is writing directly to the logical sectors, it fails. Nice to know my stick isn't as reliable as it should be....
I guess I'll have to pick up a couple of new ones at the next opportunity. I have a 16GB one, but I know that to be S L O W. Anyone got any recommendations on fast USB Sticks? Aren't there eSATA sticks?
I picked up two - I've generally had good experience with Sandisk, so as they were cheap...
Now, today, I'm trying to use one as a boot device for FreeBSD. Fail. Epically. 9 times out of 10. Why? Good question, because if I swap to the other stick, physdiskwrite just goes through. Not particularly fast, mind, but it runs.
So the only thing I can think of is that there's a couple of corrupt locations on the stick and normally in Filesystem use, these won't cause any issue. Right now, though, because this is writing directly to the logical sectors, it fails. Nice to know my stick isn't as reliable as it should be....
I guess I'll have to pick up a couple of new ones at the next opportunity. I have a 16GB one, but I know that to be S L O W. Anyone got any recommendations on fast USB Sticks? Aren't there eSATA sticks?
05/11/2011
more hardware lying around...
now I finally have a gigabit card, I can sort the firewall out - and it will use the D201GLY2. There's only one fly in the ointment - I need another harddisk. Maybe I can get away with the CF card I've bought for the purpose and I'll try that before anything else, but I'm a bit sceptical.
The previous card that was in there - a SanDisk CF Ultra II - refused to play ball with FreeNAS and I'm not convinced it's the card over the adapter.
At least the box will be nice and small. The server, on the other hand, needs to be enormous. More on that later. Maybe a loud box will encourage someone to let me have funds to get a quiet one? ;)
Bret
The previous card that was in there - a SanDisk CF Ultra II - refused to play ball with FreeNAS and I'm not convinced it's the card over the adapter.
At least the box will be nice and small. The server, on the other hand, needs to be enormous. More on that later. Maybe a loud box will encourage someone to let me have funds to get a quiet one? ;)
Bret
the five minute home studio setup
I'll keep it short. I've just done a shoot of my little monster - she's out to a party. In fancy dress.
So, of course, I want to take photos. Hmm. But how?
Let's start with the easy bit: camera. 1/100, f14, ISO100.
50mm lens.
Working distance such that the face fills around 2/3 of the frame.
One flash on the camera as trigger. Another on the floor with diffuser at 1/8 power. Directly to my right an Elinchrom DLite2 on 3.5 with a reflective brolly (shoot through would require 4.5).
Bringing the dlite towards the floor so it's lighting up underneath the hat brim means I need to drop the power by another stop (to 2.5), but the rest is fine.
Quick tip: sort your background out. Either shoot into an open doorway (!!) or get some black material for the background. Doorway is a lot faster.
- Bret
So, of course, I want to take photos. Hmm. But how?
Let's start with the easy bit: camera. 1/100, f14, ISO100.
50mm lens.
Working distance such that the face fills around 2/3 of the frame.
One flash on the camera as trigger. Another on the floor with diffuser at 1/8 power. Directly to my right an Elinchrom DLite2 on 3.5 with a reflective brolly (shoot through would require 4.5).
Bringing the dlite towards the floor so it's lighting up underneath the hat brim means I need to drop the power by another stop (to 2.5), but the rest is fine.
Quick tip: sort your background out. Either shoot into an open doorway (!!) or get some black material for the background. Doorway is a lot faster.
- Bret
03/11/2011
duh, I feel silly
I called up a store today complaining that I hadn't received a package. They found my order, confirmed it had been sent... and then said offhand "it'll fit through the letterbox and it's not signed-for".
As I'm walking out of the building, I realise that I haven't checked - and lo and behold, the package was in my mailbox at work. Ha, that'll teach me to check it occasionally.
Should also actually get the new HD droplinks for the car tomorrow, too, so the shoot is on for the 13th.
As I'm walking out of the building, I realise that I haven't checked - and lo and behold, the package was in my mailbox at work. Ha, that'll teach me to check it occasionally.
Should also actually get the new HD droplinks for the car tomorrow, too, so the shoot is on for the 13th.
02/11/2011
bit of a bargain today
actually, three.
One is a PCI gigabit network card. That's great as it means I can use a virtually silent machine as gateway.
Second is two softboxes; one 30x120 and the other 80x100 or so (don't really care, it's not quite square) from falcon eyes. If you've tried to make softboxes, you'll know how difficult it is, and these are also collapsible. Lovely stuff. Striplight, too. Now all I need is a clean car or two to photograph for the calender!
One is a PCI gigabit network card. That's great as it means I can use a virtually silent machine as gateway.
Second is two softboxes; one 30x120 and the other 80x100 or so (don't really care, it's not quite square) from falcon eyes. If you've tried to make softboxes, you'll know how difficult it is, and these are also collapsible. Lovely stuff. Striplight, too. Now all I need is a clean car or two to photograph for the calender!
hyperfocal distance - another effect of crop factor
Hyperfocal distances are interesting. No, really. I'll explain: The eye is relatively easy to confuse. I'll explain that later on.
There's something called the "circle of confusion" (coc) and this is essentially the smallest thing the eye can detect as being "sharp", i.e. not blurred. This is in reality generally around 0.2mm, but changes in Digital circles with the size of the sensor. Bottom line? For an APS-C camera (so a D7000, K5 and the like, but not µ4/3 or full frame) it's considered to be 0.02mm. More here but to be honest, we just need the 0.02. This is another reason why it's nice to know the size of your sensor
Hyperfocal distances use this coc to their advantage. If you focus a lens at a specific distance then everything between half that point and infinity will be in focus. The distance varies for the focal length of the lens used - so a 28mm has a greater hyperfocal distance than a 10mm - and the aperture used. That should start to explain why wide lenses have such a greater depth of field than a long telephoto.
There's a rather good wikipedia article on the subject of hyperfocal distances, and it includes the following formula:
focal squared / f x 0.02
that's it. It's not complex.
Example: 28mm lens, f8.
28 x 28 = 784
8 x 0.02 = 0.16
784 / 0.16 = 4900
Therefore: set focus to 5m and f8 on that 28mm SMC-M and leave it; everything between 2.5m and infinity will be in focus.
I've been testing this at work for video footage and it functions pretty well. Everything really is reasonably in focus, too, and that to infinity.
To make it really easy and to give some reference points, here a quick table, working in mm at both f8 and f16. You can do the rest of the maths yourselves.
Set focus to these distances and everything from within half of the distance to infinity will be acceptably in focus.
mm....f...distance
10....8....625
12....8....900
14....8....1225
15....8....1406.25
16....8....1600
18....8....2025
20....8....2500
24....8....3600
28....8....4900
30....8....5625
40....8....10000
10....16....312.5
12....16....450
14....16....612.5
15....16....703.13
16....16....800
18....16....1012.5
20....16....1250
24....16....1800
28....16....2450
30....16....2812.5
40....16....5000
- Bret
There's something called the "circle of confusion" (coc) and this is essentially the smallest thing the eye can detect as being "sharp", i.e. not blurred. This is in reality generally around 0.2mm, but changes in Digital circles with the size of the sensor. Bottom line? For an APS-C camera (so a D7000, K5 and the like, but not µ4/3 or full frame) it's considered to be 0.02mm. More here but to be honest, we just need the 0.02. This is another reason why it's nice to know the size of your sensor
Hyperfocal distances use this coc to their advantage. If you focus a lens at a specific distance then everything between half that point and infinity will be in focus. The distance varies for the focal length of the lens used - so a 28mm has a greater hyperfocal distance than a 10mm - and the aperture used. That should start to explain why wide lenses have such a greater depth of field than a long telephoto.
There's a rather good wikipedia article on the subject of hyperfocal distances, and it includes the following formula:
focal squared / f x 0.02
that's it. It's not complex.
Example: 28mm lens, f8.
28 x 28 = 784
8 x 0.02 = 0.16
784 / 0.16 = 4900
Therefore: set focus to 5m and f8 on that 28mm SMC-M and leave it; everything between 2.5m and infinity will be in focus.
I've been testing this at work for video footage and it functions pretty well. Everything really is reasonably in focus, too, and that to infinity.
To make it really easy and to give some reference points, here a quick table, working in mm at both f8 and f16. You can do the rest of the maths yourselves.
Set focus to these distances and everything from within half of the distance to infinity will be acceptably in focus.
mm....f...distance
10....8....625
12....8....900
14....8....1225
15....8....1406.25
16....8....1600
18....8....2025
20....8....2500
24....8....3600
28....8....4900
30....8....5625
40....8....10000
10....16....312.5
12....16....450
14....16....612.5
15....16....703.13
16....16....800
18....16....1012.5
20....16....1250
24....16....1800
28....16....2450
30....16....2812.5
40....16....5000
- Bret
01/11/2011
couple of shots from this evening
the conservatory has 10 floors. From the 9th, you get a rather good view (especially at this time of year, because it's dark early so there's still lots of traffic).
On the other hand, I still had the 100-300 on the front... and that was a bit too long. But I had no filters with me, which I would normally use for this kind of thing. Around 35mm and 1.5 - 3 minutes would be excellent, but that's not going to happen any time soon. Anyway, there's light on the inside of the building, so I'd get a reflection of myself in the pic.
These are f22, 25s, ISO80 exposures.
I quite like the way these have come out. (Click to embiggen!)
I really like the "left turn requires brakes!" and then the clean turn with the front lights.
- Bret
On the other hand, I still had the 100-300 on the front... and that was a bit too long. But I had no filters with me, which I would normally use for this kind of thing. Around 35mm and 1.5 - 3 minutes would be excellent, but that's not going to happen any time soon. Anyway, there's light on the inside of the building, so I'd get a reflection of myself in the pic.
These are f22, 25s, ISO80 exposures.
I quite like the way these have come out. (Click to embiggen!)
I really like the "left turn requires brakes!" and then the clean turn with the front lights.
- Bret
crop factor: using it
I wrote recently about crop factor. Well, here's an example of why you might want to be able to understand it....
There's a pic posted and it's from a Canon A720IS. That doesn't save any 35mm-equiv information in the EXIFs (that's the information saved with the file, which includes camera model, shutter speed, aperture etc.). It only saves the "real" number.
Now, I wrote that the real use of crop factors is in converting between systems. In this case, it's most definitely true as someone wanted to know what lens the "5.8mm" was with. The shortest lenses I know of are around the 8mm mark and they are fisheyes - the pic was too "real" to be really 5mm in 35mm world.
This - http://en.wikipedia.org/wiki/Image_sensor_format - tells us the crop format for the 1 2/5" sensor used is around 6, so 6 x 6 = 35mm or so.
So, I think you'll find that the field of view represented by the pic is pretty close to a 35mm on FF or 20mm on APS-C.
Couple of tips:
- at least Windows 7 has the option to show this information in fields in Explorer (try "35mm focal length")
- PhotoME is a great application to read this information from pics, including in my case the camera temperature and shutter actuations.
- Bret
There's a pic posted and it's from a Canon A720IS. That doesn't save any 35mm-equiv information in the EXIFs (that's the information saved with the file, which includes camera model, shutter speed, aperture etc.). It only saves the "real" number.
Now, I wrote that the real use of crop factors is in converting between systems. In this case, it's most definitely true as someone wanted to know what lens the "5.8mm" was with. The shortest lenses I know of are around the 8mm mark and they are fisheyes - the pic was too "real" to be really 5mm in 35mm world.
This - http://en.wikipedia.org/wiki/Image_sensor_format - tells us the crop format for the 1 2/5" sensor used is around 6, so 6 x 6 = 35mm or so.
So, I think you'll find that the field of view represented by the pic is pretty close to a 35mm on FF or 20mm on APS-C.
Couple of tips:
- at least Windows 7 has the option to show this information in fields in Explorer (try "35mm focal length")
- PhotoME is a great application to read this information from pics, including in my case the camera temperature and shutter actuations.
- Bret
audio - quick link
now I'm involved in a lot of audio stuff at work, too, so this is a quickie: http://www.mcsquared.com/wavelength.htm
We've got a conf room that echoes. Two minutes with the Focal test disc #2 tell us approximately where the resonances are - around 500Hz - and therefore how we can begin to deal with them. In this case that probably means thick curtains, spaced at 6" or so apart / 17cm. Let's see if it works...
- Bret
We've got a conf room that echoes. Two minutes with the Focal test disc #2 tell us approximately where the resonances are - around 500Hz - and therefore how we can begin to deal with them. In this case that probably means thick curtains, spaced at 6" or so apart / 17cm. Let's see if it works...
- Bret
droid and google
I've been using a 'droid phone (htc wildfire) for work and to be honest, I'm nonplussed.
I use an N900 on a daily basis and there are still two S60 and one S40 Nokias in the house. I've used S90, S80 and S60 over a period of years.
Things that *really* bug me about the htc:
- I expect a phone to act as one when it's connected to a PC, not just mass storage. DUN as a minimum.
- Keyboards that are that hard to use for people with "sausage fingers" are not funny. My little monster found it great - I hated it. As did the other half.
- When the keyboard covers half of the field you're supposed to be entering, that's plain silly.
- the battery life is a joke (2 days max, without using it)
- why can't I take screenshots?
- why can't I close an application?
- Why on earth do I NEED a google account to install even an app? I can't even download one from the googlemarket without a google account - and this one won't work, because there's no SIM in the phone, so therefore I can't have the account confirmed.
If you think that last point through, that's pretty damned close to the glass citizen. Google would then know:
- what phone I have
- what apps are theoretically on it
- where I am
- my opinions via blog and / or plus
- my acquaintances across the planet via plus
- which blogs I read
add into that a significant proportion of my search history and away we go....
My next phone will not be droid. Probably an N9 or a Lumia.
- Bret
I use an N900 on a daily basis and there are still two S60 and one S40 Nokias in the house. I've used S90, S80 and S60 over a period of years.
Things that *really* bug me about the htc:
- I expect a phone to act as one when it's connected to a PC, not just mass storage. DUN as a minimum.
- Keyboards that are that hard to use for people with "sausage fingers" are not funny. My little monster found it great - I hated it. As did the other half.
- When the keyboard covers half of the field you're supposed to be entering, that's plain silly.
- the battery life is a joke (2 days max, without using it)
- why can't I take screenshots?
- why can't I close an application?
- Why on earth do I NEED a google account to install even an app? I can't even download one from the googlemarket without a google account - and this one won't work, because there's no SIM in the phone, so therefore I can't have the account confirmed.
If you think that last point through, that's pretty damned close to the glass citizen. Google would then know:
- what phone I have
- what apps are theoretically on it
- where I am
- my opinions via blog and / or plus
- my acquaintances across the planet via plus
- which blogs I read
add into that a significant proportion of my search history and away we go....
My next phone will not be droid. Probably an N9 or a Lumia.
- Bret
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