micro adjustment not working proberly

Robbo

Robbo

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Yes
just messin on with the mirco adjustment. And through the test I done it came out that 0 was the best. Working from the 50x focal distance etc

How ever when I shoot closer objects, all settings and zoom the same, I find that +8-10 is better??

What the hell?

Is this normal or what?
 
Robbo said:
Is this normal or what?
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Yes - I've said here numerous times that fine tune is simply not suitable for zooms.

How can you have a one-size-fits-all single setting for all focal lengths and focal distances?

Answer: You can't.

Forget messing around. If you have a faulty item, get it serviced.
 
puddleduck said:
Yes - I've said here numerous times that fine tune is simply not suitable for zooms.

How can you have a one-size-fits-all single setting for all focal lengths and focal distances?

Answer: You can't.

Forget messing around. If you have a faulty item, get it serviced.
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No faulty item or anything, I thought thought I would test it out more than anything.

Just going from Canons 'zoom range instructions' ..... obvious its still a load of bull? lol
 
A small discrepency at very close range is quite common. Which is why Canon recommend testing at a greater distance, for the reason that if you correct it for close ups, you will throw it out at longer range which is presumably where you use the lens most.

All AF systems work to a tolerance, and close up pushes that tolerance to the max. +8 or so doesn't sound too far out to me. What lens are you talking about, what focal length, what distance, how far out do you reckon that is and is it significant distance in practical terms?

Unless you have got a massive discrepency, ie a fault, then the chances are sending it back to Canon will do nothing more than you can do yourself with microadjust. That is, choose the best compromise setting for you.

What's it like at 25x focal length?
 
The test I worked from about 3 meters and it was pin point on at '0' using 55mm

When using same focal length just short of a meter away and found it went up to around + 10 ish.

Like I say it's working fine, I was mainly testing stuff out 'just to see', tbh it's mainly going to be used for portraits, landscapes and a few gigs of my mates band. So not really going to be used at that metre working distance.

First time I tested a lens so wasn't sure what was normal, as I know zooms aren't the best to do this with.

As it's fine at the recommended focal and working distance I take it I leave it as is?

It's canon 17-55mm 2.8
 
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Have a look at this thread on AF microadjust, and have a go with the cunning DIY device shown in post #22 ;) http://www.talkphotography.co.uk/forums/showthread.php?t=256831

One of the problems with AF testing is that when you go too close, it's very easy to let testing errors creep in. We are talking about a few mms here. Have a go with the cerial box and a rule, and get some accurate and consistent numbers down. Then take a view.
 
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100% in photoshop and focus charts are two of the biggest problems in photography today.
 
hollis_f said:
Which is a very strange attitude. Why would one avoid a technique that can pull the very best results from one's equipment?
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Because I expect a lens to perform right out of the box and do see why I should mess around with them myself, I tried once when I had a mk3 and 300f2.8 and found it needed +15 to get the best out of it and I was not happy at all, but the lens was perfect on every other body it went on, so if I have a problem I just let canon sort it out.
 
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