Do you microadjust your lens?

I definitely check every lens and have several that benefit from AFMA.  In my opinion this is one of the best features to come out in recent history for SLR's.

i have never felt any need to F* with my "L" lenses because they were sharp and tuned right out of the box and still are! some people like to fix something that is not broke and that is when they screw up, IMO! i am not suggesting that all lenses are tuned correctly from the factory, obviously there are ones that need fine tuning, which is worth the effort.

It is pretty tedious at first but once you get the hang of it, it isn't so bad.  If you are already happy with your results it probably isn't worth bothering with.  Most of my photography is with long focal lengths where problems are easier to notice.

The 600mm f4L IS II that I had for a while needed AFMA of +6 on all of my bodies and it sure made a difference once I corrected it.  The first 400mm f/4 DO mk2 that I tried needed +18 right out of the box.  The DO was so bad that it was exchanged right away.  Neither of those lenses is a budget model.  I wouldn't just trust that because it is an "L" lens that it can't benefit from AFMA.  Having said that my 100-400 mk2, 70-300L, 300mm f/2.8 mk1 and mk2 were all perfect out of the box.  If you are going to spend all that money on a lens I suggest it is worth at least checking that the AF is properly calibrated.

BirdShooter7 wrote:

The 600mm f4L IS II that I had for a while needed AFMA of +6 on all of my bodies and it sure made a difference once I corrected it. The first 400mm f/4 DO mk2 that I tried needed +18 right out of the box. The DO was so bad that it was exchanged right away. Neither of those lenses is a budget model. I wouldn't just trust that because it is an "L" lens that it can't benefit from AFMA. Having said that my 100-400 mk2, 70-300L, 300mm f/2.8 mk1 and mk2 were all perfect out of the box. If you are going to spend all that money on a lens I suggest it is worth at least checking that the AF is properly calibrated.

no that you have mentioned it, i might try that! i know my 600 f4.0 II doesn't do well with both canon TC IIIs, so that might be one reason. i know my 300 f2.8 II is very sharp with/without TCs. but i might try my 100-400 II as well. my 100-400 II is pretty sharp without TC but slightly mushy (slightly noticeable) with using 1.4 III TC.  i have plenty of time so i could spend a few day doing it if i have to once the weather warms up a bit! thanks for the tip.

I currently have around 15 lenses and have had and sold around 30+ other lenses and with a few exceptions they all needed some adjustments.

Small offsets were visible on 5Dc, but every offset is visible on 20+ Mpixel camera's when cropping and definitely when pixel peeping. I think it is a very little effort with a very significant impact when shooting lenses wide open. It doesn't fix camera misfocus though :-).

TheDigitalDonbavand wrote:

In particular how to ensure the target and sensor are completely parallel.

I believe that if you tape a flat mirror to a flat wall (the target in this case), it will solve that problem. When you see the camera lens in the center of both the mirror on the wall and the viewfinder of your camera, you will be parallel both horizontally and vertically.

Don't forget to find out the MFA needed for each separate lens with each separate body. Your body could be out too. Don't dial in a setting you found from using the lens on another body...

The good thing about AFMA is that is your find that you are getting worse results with it all you have to do is turn it off and everything goes back to normal.

sceneIt wrote:

I adjust them, and if they aren't accurate 99% of the time I send them back to the factory with an 8x10 of me taking a dump on their corporate logo....

That's classy.