Focus adjustments question

[Chaz Photos]

I have been fine tuning the focus on my lens but one question on a zoom I have n=been doing it at the longest setting is this right?
Or should it be done mid way like if doing the 100-400mm
should it be done at 400mm or 250mm
Is there any where to tell you how it should be done?

 

[swag72]

When I got mine done by lehmanns they suggested that the best focal length to micro adjust on was the length most used. I did mine on 400mm for that reason.

 

[webbEvents]

I've just done this with 2 of my lenses, been out this afternoon to see if I can see any real world difference. (they seemed OK before adjusting) Using the "Moire" method with the downloaded image. (All OK, no viruses or dodgy pop-ups/links)
http://www.northlight-images.co.uk/article_pages/cameras/1ds3_af_micoadjustment.html
Webby

 

[Chaz Photos]

When I got mine done by lehmanns they suggested that the best focal length to micro adjust on was the length most used. I did mine on 400mm for that reason.

So you only had the one lens done then?

 

[Robbo]

How do you tune the lens?

 

[Ceejay]

If you look at Webb Events link, Canon suggest the longest focal length, so for your lens 400mm.
C

 

[swag72]

So you only had the one lens done then?

I only had my 100-400 done when I sent it off to Lehmanns. I was happy with the others so didn't bother with them. Have done them all now though.

 

[philthejuggler]

How do you tune the lens?

Use a 50D / 5D MKII etc that has micro-adjustment. It can remember a number of settings for different lenses. Interestingly if you want to also use an extender you have to tune the lenses with and without and it stores the settings seperately.

Phil