Canon lenses calibration

Started 5 months ago | Discussions thread
OP CESA Regular Member • Posts: 477
Re: Canon lenses calibration

Zeee wrote:

Zeee wrote:

CESA wrote:

Zeee wrote:

J A C S wrote:

Why are you doing this? Do you see AF problems?

One of the mistakes people make is to do the calibration with the target too close. This would create more problems than it would solve - been there, done that.

This is very true. That is why I called that PDF link the most comprehensive document. I had lots of links to various Canon information. Some said 50X, others said at location, etc. Even the manuals say best to MFA at location. Then add all the home made versions, etc. There were just too many options which was one reason I never liked MFA. FoCal which follows the sensor parallel to target method made my life easier. I followed it's minimal distance recommendations.

Just use the lenses you normally would and inspect the shots carefully for AF errors. Do MA only if you see consistent front or back focus.

Hi both.

I have purchased the FoCal software to perform the AFMA to my lenses specially the 85mm f1.2.

I have done several tests including at different distances or in this case at 2.7m and 3.1m.

The AFMA returned AFMA value of +5. Nothing like the +17 that I was talking about. But there is a catch.

After performing this calibration, I went out to take some close shots or in this full body and some half chest shoots (what's that, 1m and 1.5m or so) and pictures were not perfectly sharp.

Changed the AFMA to +17 and bang on at those distances (half-chest and full body).

Followed everything they recommend with exception of using their target, the ones they sell which I am still waiting for delivery. to repeat the tests. I have printed the target at the local supermarket so it is what it is and don't know if it is suitable. But have repeated the test several times and it was more or less consistent in the sense that the AFMA that returned were pretty close +5 and one time said between +4 and +6 but then ended up in +5 after continuing the test.

Actually, before performing the tests I went out and had the AFMA set to +5 and pictures taken at say 2m or 2.5m were not 100% in focus/sharp f1.2 and f2.

Now, next time I am gonna take a walk will change the AFMA to +17 and will do some tests.

Will also perform the test at 1.5m and see if the camera will show the same AFMA that I got by doing real life tests.

That being said I question the efficacy of this software.

Well known Dustin Abbott has mentioned in one of his videos showing how to calibrate lenses that some of the setting FoCal came out after the test he didn't agree.

The testing conditions, lighting specially probably influence a lot the outcome as well.

I am wondering at which extend this software usefull or not. But had to get it to see by myself. Dustin teaches how to perform the test manually using their targets and the LIVE VIEW shot as starting point.

Additionally did the best aperture and also the AF consistency and they were not consistent as well. That is the best aperture for the sharpest aperture, it gave me different values test at different distances from the target (see above) and the AF consistency gave me slight differences but I was expecting to be the same.

Any comments?

Not sure what to say about that part. It has always been bang on for me. I took me 3 days to settle on +13 for my 7D2, 100-400 II and 1.4 @ 560mm. FoCal gave me +13 in 5 minutes. It took me 3 days because I always second guess myself. Maybe they can do a refund I you don't like the product.

On the other hand +17 is a lot IMO. I would not except that. I purchased a 70-200 2.8 II and it needed about +15 at 200mm without a TC on two bodies. I purchased FoCal specifically to verify it. Two Canon techs at New Jersey service told me that with high numbers like that use MFA to get by but it should be serviced. They found a mis-calibrated board.

Back to the 7D2, 100-400 II and 1.4. Without the TC it only needed +3. The TC on primes needed very little as well so it wasn't the TC and the lens was fine. I could only conclude that since the 100-400 II has many moving parts it could be in spec but some components are on one end or the other of said spec. I wasn't sure what Canon could so I decided to leave that particular lens TC combo alone. That was the only exception I have made to date. I know of one more person that had those same results.

I followed a philosophy of a +-5 being the tolerance I'd leave alone. Anything higher would go in. +-5 to 10 would have been a tougher decision but I have never come across that. If it is out it is out badly and that only happened once to me. I am in minority when it comes to those thresholds but a few years later I found this article so I'm not the only one. Canon told me the same thing.

Sections 10, 11, and 13.

Have you tried FoCal on other lenses?

Haven't tried it yet as didn't have the time yet. Will probably try it on my 50mm next, the f/1.8 version and see how it compares to my real life calibrated AFMA value which is under 10 BTW. The macro will be the next one.

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