digital paradise wrote in post #17299963
I never thought the camera was defective. If it was no one would be able to take those great images. I was always under the assumption that it got out of spec during manufacturing.
I tried my trusty 300L F4 IS first and it was the same. I have used that lens starting the 30 and 40D that had no MFA and my 50 and 7D and I did not MFA and I can show you tack sharp images from all those cameras. Of course F4 is not razor thin DOF. I sent my 70-200 II to new jersey about a year ago because it was just not right so the shot above was taken with a factory calibrated lens. Actually Dot Tune confirmed it was off but I kept getting difference results. My shooting partner tried it and thought so as well so I decided to send it in. First lens in my collection that ever needed a factory tune up.
That same day when I got the upper shot I took a series of shots (no MFA) of planes with my 5D3 and the 70-200 and they were all bang on. So two trusted lenses were doing the same thing on my 7D2.
I have read the lens rental document and almost every link and article posted. I understand that there is variation in the manufacturing that has upper and lower specs and the lens one be at one end and the cam at the other. Because our company got into a total quality initiative we learned about statistical process control in manufacturing. It was pretty interesting.
I don't really have a wide enough house to do MFA tests at correct distances and it os -25 Celsius out there. I have Focus Tune and just ordered the MKII target with the new ruler which I'll try it out.
To me 13 MFA is not a tweak. That is just plain out. Actually a member here - big country got his back from Canon a few days and just posted shots at Fred Miranda. They looked good. I'm not sure he has done that here yet. I did not check.
My error was I should have thought of this earlier but I never expected that much MFA was needed. Like I said a first for me. Indoor shots were right on but other commitments and with bad weather there was a as much time to test in the field as I would have liked. I was trying to rule out user error first and finally concluded it couldn't be me. Either way that cam was going to Canon.
It sounds like I am newer to this than you but we have similar results.
I am a 2x5D3 shooter for weddings with all the L glass that wedding people use.
I started a thread earlier because I got the 7D2 and then decided to actually do a Dot Tune test - and that is when I found out that nearly all my lenses were forward focused (according to this method) but I never really noticed it with the 5d - except I wasn't completely happy with my 85 1.2 at 1.2. So, I found out, that according to Dot Tune, all my lenses were at least +4 and a few were +8 to +10. I then read that type of light mattered and maybe it was all a Tungsten thing.
All the above said, and lets remove the AI Servo issues for now, I think I have concluded that what we are all talking about is an AI Servo speed of adjustment issue revealing that the DofF is smaller on the smaller 1.6x sensor and then that has revealed that in certain types of light, a bunch of L lens are by spec front focused.
I have now dialled into both my 5D3s and 7D2 MFA of +4 to +8 for every single lens and even +10 on a few - and everything on all cameras and all lens is tack sharp - but yes I don't nail all frames using AI Servo in a 20 frame sequence as I think Intel needs to up the CPU speed another 100 fold for that to happen - or I have to stop using a razor thin DoF on a fast and erratic moving subject.
Hockey and wedding photographer. Favourite camera / lens combos: a 1DX II with a Tamron 45 1.8 VC, an A7Rii with a Canon 24-70F2.8L II, and a 5DSR with a Tamron 85 1.8 VC. Every lens I own I strongly recommend [Canon (35Lii, 100L Macro, 24-70F2.8ii, 70-200F2.8ii, 100-400Lii), Tamron (45 1.8, 85 1.8), Sigma 24-105]. If there are better lenses out there let me know because I haven't found them.