AFMA - what range do you see in your body and lens combos?

YuengLinger

Print the ones you love.
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Dec 20, 2012
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drolo61 said:
Just calibrated my new 5DMarkIV to my existing range of lenses using FoCal 2.4.

I have
50 1,4
135 L 2,0
24-70 L 2,8 II
70-200 L 2,8 IS II

I got AFMA values between +1 to +8, with "excellent fit" for the "L"s and a relatively inconsistent focus on the 50.

Would you consider that range "normal"?

Same as yours, but on 1.4 tele-extender, +12
 
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AlanF

Desperately seeking birds
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Aug 16, 2012
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Go into the compare menu in FoCal and it will give a chart for the range of values found by other users for each of your lenses on the 5DIV as well as your other bodies. It's a useful guide and can stop you worrying. For example, my 300mm/2.8 II is +7 on the 5DIV and was +9 on my old 7D, but I now know that these values are typical. In general, most of my other lenses hover around 0, but also find that the 1.4xTC can raise to +10.
 
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this is a meaningless question. a body that is off by -20 and a lens that is off by +20 will together be zero, while a body that is -5 and a lens that is -5 will together be -10. that certainly doesn't prove anything about the quality control of anything. end of the day, if your pairing afmas to zero, or to +/-20, or anywhere in between, you are good. you only have an issue if +/-20 isn't enough.
 
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Whenever I upgrade to another camera, I will definitely get a model that supports AFMA. I recently bought an ancient 1D mark II that is currently being serviced by Canon for backfocusing (something that I could have easily corrected for myself if it supported AFMA).
It was backfocusing on both my Tamron 28-75 F2.8, and my Canon 50mm F1.8 STM.
Canon tested the 50mm lens and said it was spot on (and that the camera was the problem).
 
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Mar 25, 2011
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Something that is often overlooked, but is a real issue is shipping damage that throws AF out on lenses. Cameras are usually closer to being in spec, but can also suffer AF inaccuracies.

I found quite a variation from camera / lens combination from lens to lens and camera to camera. Generally, most lenses were well within specification but I had a occasional combination that was far enough out to benefit from AFMA. The adjustment amount is normally different from camera to camera, but some lenses were perfect on various bodies.

I attached a old chart which compares the AFMA settings originally obtained from using one of the commercial calibration tools to using Focal on my 5D MK II and 7D. I will not buy a camera which does not have AFMA unless its DPAF, which uses contrast detect as a final tweak to the autofocus, or it did originally.
 

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