# AFMA not really needed in 5D MKIII?



## Aditya (Jun 1, 2013)

I've been using a 5DMKIII for several months now keeping my MKII as a backup. I've found AFMA has sometimes made a significant difference with the MKII and certain lenses like my 135 f2L (+8). I've put a couple of my most used lenses through the AFMA procedure that Neuroanatomist described http://bit.ly/14ii3An using a SpyderCal target and have noticed a very minor adjustment was 'needed', if at all (+2 or so on a 70-200 2.8 IS II and a 24-70 2.8 II). 

After buying a new 85 1.2 II I tried doing the AFMA process I found that whenever I made any + or - adjustments the focus results were off and relatively inconsistent in a illogically maddening sort of way (10+ shots at -5, -3, -1, +1, +3, etc.) and that the neutral 0 position actually produced the most consistent in-focus results (not front or back focusing too much). I was pleasantly surprised and wondered if the AF system in the MKIII is _that _good?! So far most of the shots I've taken with the 85 1.2 (when focus hits what I want) have been wicked sharp at 1.2-1.6, which is great. 

Anyone else noticed a similar (awesome!) phenomenon with a 5D MKIII? Did I just get super lucky with lens and body combo? The body just came back from CPS for a multi-controller button replacement (and all tuned up with newest firmware) and the lens is brand new.

Photo of a friend with focus on left eye taken from 4 or 5 feet away http://sdrv.ms/17dVD9V

Focus on orange slice http://sdrv.ms/17dVTG9


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## neuroanatomist (Jun 1, 2013)

I suspect you got lucky, which isn't a bad thing!


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## Mt Spokane Photography (Jun 1, 2013)

I find that most lenses are close enough that only software like FoCal and a very carefully setup test can detect the AFMA setting needed. Most, but not all of my lenses are very close. 

Its a combination of lens and camera body, if you have a dozen lenses, it would be pretty unusual that all were a perfect match.


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## mrmarks (Jun 2, 2013)

It depends. My 5D3 body did not need any afma for all my five l lenses. Recently I had to send in the body to canon service for a sensor change. After the sensor change the afma drifted to about +5 to +8. I contacted canon about it and they asked me to resend it in for focus calibration. Some accident happened during the af adjustment procedure at canon and they burnt the board (the tech told me that the af was on for too long during testing). I received the new body and after checking the af, it did not need any afma at all for all five lenses. 

So, it seems that new 5D3 bodies with factory settings seems to not require any afma. However, the local canon service center may not have the same factory equipment for sensor af adjustment, and the af calibration may not be 100% correlated to the factory equipment. Therefore if any sensor change/reassembly is done at the service center, it may require some afma.


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## Act444 (Jun 4, 2013)

I think you just got lucky...

I have had 2 lenses so far that were not focusing optimally at 0...and needed some adjustment. 
Then again, it's possible that it might be the lenses themselves and not the camera body (one needed +, the other -)


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## tjlawler (Jun 5, 2013)

Yea, you got lucky. I noticed that mine was front focused (it would be focused slightly in front of the marked focus spot. Since I mainly shoot birds with long lenses and want to control the DOF this was very obvious (to me). 

Tom


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