Should AFMA on a Set of Lenses Have Similar Spread from One Body to Another?

I have slowly been getting time to AFMA my lenses using Focal on my 7DII, after upgrading from 7D. I've noticed something that is strange to me, but maybe it is normal and I will ask this experienced group. These are the only two cameras I've ever had with this ability. The change in AFMA is not going in the same direction with all the lenses.

35L:
7D -2
7DII +2

50L:
7D -4
7DII -11 (-12 the first attempt but program crashed before saving report)

70-200 2.8II @70:
7D -1
7DII +4

70-200 2.8II @200:
7D 0
7DII +6

I do have some others that were AFMA on my old body that I'll eventually get the time to compare and see the trend. The 35 and the zoom seem consistent enough, but the 50 going the other way by such a margin seems odd to me. Should I be concerned? I used Reikan FoCal in both cases. The old 7D seemed very down the middle, with everything I had for lenses falling in the +- 5 range and better.

As a side note, I hope Reikan come out with an upgrade again soon. I had managed to AFMA a couple lenses before a trip, but only because I read the result right before the program crashed. The only way to stop wasting time and shutter count was to work in manual mode, not terrible, but not as convenient.
 
Mar 25, 2011
16,848
1,835
The fact is that bodies also have a tolerance, so AFMA can be due to a body, but is likely a combination of lens and body tolerances, you are compensating for both.

Different camera models, particularly crop and FF will show a much wider difference with as given lens because a AFMA point is equal to 1/8 of the depth of focus. That means that it is different for each lens and on different sized sensors as well as body tolerances.


http://www.the-digital-picture.com/Photography-Tips/AF-Microadjustment-Tips.aspx
 
Upvote 0
As explained to me by a Canon tech; the lenses should all be calibrated to their factory spec in order to allow a uniform calibration of the body to technically require 0 AFMA.

So, if a lens is in on one body and out on another, chances are greater than the body is out but there's certainly a possibility that the lens is marginally out.
 
Upvote 0