Lens Calibration

This question about Canon DSLR cameras and various lenses has four parameters:

1. If I have a third party lens (such as a Tamron or Tokina) that I use with my Canon DSLR cameras and it front or back focuses; can I use the Canon calibration to fix this?

2. If I use the same lens with more than one camera body, do I need to calibrate the lens for each body and will the setup remember which lens/body combination I am using?

3. Is lens calibration a one-time thing or do I need to check the lens regularly?

4. Will older lenses such as the EF 50mm f/1.8 Mk.1 or the EF 135mm f/2.8 SF calibrate if needed?

RPCrowe wrote in post #18676519
This question about Canon DSLR cameras and various lenses has four parameters:

1. If I have a third party lens (such as a Tamron or Tokina) that I use with my Canon DSLR cameras and it front or back focuses; can I use the Canon calibration to fix this?

Yes.

RPCrowe wrote in post #18676519
2. If I use the same lens with more than one camera body, do I need to calibrate the lens for each body and will the setup remember which lens/body combination I am using?

Yes. Calibration is a function of the body.

RPCrowe wrote in post #18676519
3. Is lens calibration a one-time thing or do I need to check the lens regularly?

Generally it's a one time activity though I do check mine from time to time when I get bored. They don't change much.

RPCrowe wrote in post #18676519
4. Will older lenses such as the EF 50mm f/1.8 Mk.1 or the EF 135mm f/2.8 SF calibrate if needed?

Yes, calibration is a body function.

Thank you GJL.

I also found this information. I was calling it "calibration" when the correct Canon terminology is micro adjustment...

https://www.learn.usa.​canon.com/app/...de_de​sktop.pdf

Be advised that for best results, Canon suggests using MFA on each camera/lens combination, at the distance you will be shooting, and in the light you will be shooting in. That is (would be, if I ever did it) incredibly time-consuming.

I knew what you meant. One thing to keep in mind though is that you can't MFA (micro-focus adjust) 2 lenses that are the same to be different. If you have 2 50mm lenses, the camera sees it as the same lens. I'm not sure if the newer Canon cameras have fixed this or not.

gjl711 wrote in post #18676601
I knew what you meant. One thing to keep in mind though is that you can't MFA (micro-focus adjust) 2 lenses that are the same to be different. If you have 2 50mm lenses, the camera sees it as the same lens. I'm not sure if the newer Canon cameras have fixed this or not.

Incorrect. My 80D, and my 6D, not only allow for multiples of any focal length, they allow for multiple copies of the EXACT SAME LENS. By entering a serial number, I can register 2 (or 20) copies of the 70-200 f/4L IS, or 24L II, or whatever. It seems the only limit is the alloted 20 slots for lenses.

Bassat wrote in post #18676644
Incorrect. My 80D, and my 6D, not only allow for multiples of any focal length, they allow for multiple copies of the EXACT SAME LENS. By entering a serial number, I can register 2 (or 20) copies of the 70-200 f/4L IS, or 24L II, or whatever. It seems the only limit is the alloted 20 slots for lenses.

I guess you missed " I'm not sure if the newer Canon cameras have fixed this or not."

gjl711 wrote in post #18676848
I guess you missed " I'm not sure if the newer Canon cameras have fixed this or not."

Missed nothing. It wasn't true for old cameras, either. My 6D is 6 years old.

MFA will not correct for back and front focusing. It only corrects for either one (one direction). Here is Canon's latest. I have read everything Canon published on this and this best IMO. Most current as well I think. First time they have mentioned a light source. Open the PDF and page 5 has a good summary.

http://www.learn.usa.c​anon.com …oadjustment-landing.shtml

I use FoCal and they have some good info. If you can't do this at the location (from your manual) or the distance you normally shoot then they recommend 50X the focal length which can be impractical for longer lenses. FoCal uses shorter distances for longer lenses and explains why on page 2.

http://s449182328.webs​itehome.co.uk …20Test%20Distan​ce_1.1.pdf

It has been a while since I have looked at that page. It used to be 25X across the board. Now they have specific minimal distances for each focal length. Here is their distance tool. They refer to their target but you can use anything you want if you are doing it manually.

https://support.fo-cal.co.uk …tion-target-distance-tool

I tested my new purchase, a used EF 85mm f/1.8 lens in mint condition and the AF was spot-on... In fact, the only Canon lens with which I have had focus problems was an EF 17-40mm f/4L used on a 40D, years ago...

Bassat wrote in post #18676600
Be advised that for best results, Canon suggests using MFA on each camera/lens combination, at the distance you will be shooting, and in the light you will be shooting in. That is (would be, if I ever did it) incredibly time-consuming.

Not always as time consuming as you might think, especially for primes. Now if you use Sigma's hub to calibrate their lenses, there are 4 different settings for primes, and 16 settings for zooms which you need to calibrate, and adjacent settings can interact with each other. And of course you can then only use that lens with the camera it's optimised for.

In my experience with Canon's in body adjustments, while you may not be completely optimising a lens, experimenting with adjustments in normal shooting, especially with a lens you are very familiar with, can produce significant improvement over its non calibrated state. This is very useful for lenses that are clearly soft at the focal plane due to front or back focusing. It still takes attention to detail, and it does still take time and effort, but the results are worth it.

My EF 35mm f/2 IS USM and my EF 70-200 f/4L IS USM were both calibrated by me on my 7D2 over time though experimentation to correct softness and are now both significantly sharper as well as more consistent. My Sigma 18-35 mm f/1.8 worked almost perfectly on my Canon 60D but was so way off, especially at f/1.8, on my 7D2 that I was seriously considering selling it. With a little experimentation, it went from unusable to excellent in that camera.