# Canon 24-70 f2.8 II. How much AFMA does your copy need? What's acceptable?



## drjlo (Jun 18, 2013)

My copy of 24-70 f/2.8 II needs -9 at wide end and 0 at tele end on my 5D III. My Canon 70-200 f/2.8 II needs 0 at either end, and my 100L also needs 0. Some of my fast primes including 35L, 50L, 85L II range between -1 and -3. 

A brand new Canon 17-40 f/4L I just borrowed needed -6 at wide and 0 at tele. 

-9 seems a tad too much for a $2100 lens, so I'm just wondering what 24-70 f/2.8 II owners have experienced with AFMA (and 5D III)? Is it worth sending in the lens to Canon while still under warranty for calibration?

Is my copy of 5D III partly at fault here, as the body seems to need Minus AFMA on lenses, never positive. The body is out of warranty, but should I send in both the 24-70 II and body to Canon for calibration together (does Canon even calibrate a specific lens+body combo?). 

Any help would be appreciated.


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## neuroanatomist (Jun 18, 2013)

Mine is W = 0 and T = +5. I'd also recommend testing at intermediate focal lengths. Mine was +1 at 35mm and +3 at 50mm - those values fall right on the linear regression between the ends, and if they didn't, I'd have exchanged the lens or sent it to Canon. 

FWIW, my 70-200/2.8L IS II is +2 at both ends and at 135mm.


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## drjlo (Jun 18, 2013)

I just talked to Canon CPS, and they are implying to me that their "unofficial" guideline for acceptable AFMA is around 10. That seems like a lot since the difference between 0 and -9 is quite noticeable to my eyes. 

They suggested that if both lens and body are "off" in same direction, it may end up too much and recommened I drop off both the lens and body to be calibrated together, so I guess I'll do that when I have time to make the drive over there..


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## Act444 (Jun 18, 2013)

-1 at both ends seemed to help in my case. But I have not been able to test in "real-world" situation yet.


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## Dylan777 (Jun 18, 2013)

I left my @ zero. With the sharpness I'm getting from my copy(1st patch), I feel like, I do not want to make anymore ajdustments. 980ish @ f2.8 through Focal without AFMA 

I wish I could say that to my 50L(-3) in term of sharpness @ wide open ;D


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## RMC33 (Jun 18, 2013)

+1 on the wide end 5d3, 0 for my 1Dx
-2 on the tele end for 5d3, -1 for my 1Dx

5D2 overall was -1.


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## Mt Spokane Photography (Jun 18, 2013)

I don't worry unless it exceeds about 14. 9 or 10 is fine.

My 24-70 MK II on a 5D MK III was -5 tele and +1 Wide.

You can see other results at Reikan Focal. I've pasted in the chart, the box in the lower right corner shows the AFMA spread over 10 bodies.
AF Microadjustment Spread 
Again, if have the information available we will show the spread of the AF Microadjustment/Fine Tune values determined by FoCal for the chosen camera/lens combination:

The title will show the number of tests and number of unique bodies used for these results
The height of each bar shows how many of the camera/lens combinations are using this value of AF Microadjustment/Fine Tune
The colour of the bar shows it’s distance from 0 – *red *indicates front focus, and *blue *indicated back focus.


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## drjlo (Jun 19, 2013)

Testing this 24-70 II some more, I am somewhat dismayed by what I find at close distance, wide open, at wide 24mm end. Compared to where live view focusing stops, even after AFMA, the phase detect AF is hit-and-miss, even on tripod. Often the initial half-press of shutter will be quite a bit off, then a repeat half-press or two will get it to where live view stops. Where it stops also seems to differ based on whether I'm focuing from infinity or MFD side as well as distance from object. At other times, it focuses right at first half-press. This doesn't seem to happen at the 70mm end. Phase detect couldn't be this bad relative to live view in general, could it? Guess will see what Canon service will say/do.


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## Scott_McPhee (Jun 27, 2013)

I've just calibrated my 24-700 f2.8 L II using Focal and I got w:+1 and t:+1

This was a brand new lens so it may "settle" after some use.


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## yablonsky (Jun 27, 2013)

No need to adjust. Good @ zero


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## gferdinandsen (Jun 27, 2013)

At 24mm, the focal length closest to shat I most often shoot, FoCal suggested no changes be made to AFMA.


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## kaihp (Jun 27, 2013)

W: -3, T: +0


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## lastcoyote (Jun 27, 2013)

zero AFMA needed on mine. took a few replacements to get an issue free copy though (and i don't mean focusing issues). my patience has been rewarded with a super sharp copy.


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## Scott_McPhee (Jun 28, 2013)

I find it amazing that we are paying so much money for a professional lens and we are still getting "bad" copies sent to us.

Is Canon's QA that poor that these lenses are being sold to customers?

At this price I would expect all of the lenses to require minimal AFMA if indeed any at all.

I must have been lucky to get a copy that required +1 at both ends, which is a negligible adjustment really.


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## Phenix205 (Jun 28, 2013)

+1 W -3 T. I did several tests, the results were somewhat inconsistent at the T end. The value varied from -5 to -2 and I settled at -3. What bout the aperture sharpness and AF consistency testing results? The sharpest aperture for mine was either 2.8 or near 5.0. Again, some inconsistent results were seen but it could be due to the lighting. I also tested the lens using a 36" x48" ISO12233 chart. Softer at 70 mm in corners. In real world shooting, the lens performed fine.


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## Viggo (Jun 28, 2013)

Mine is +1 at both ends, and it was 0 at 35 and 50, and real world shots confirms this as well. 

Mine is 2012 edition (with the old style lens cap) and it is much more consistent with sharp results than the 2013 I exchanged due the infamous clicking noise with the zoom ring. 

Up close the 24-70 mk2 is noticeably softer than at a meter or more.


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## iso79 (Jun 30, 2013)

Dumb question but how do I find out how much AFMA my copy needs and how do go about figuring out how much I need to adjust?


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## TM (Jun 30, 2013)

My mark I was horrible with inconsistent focusing. Sold it for a new Mark II and thankfully my copy is consistently sharp and doesn't require micro-adjustmenting.


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## Scott_McPhee (Jul 1, 2013)

iso79 said:


> Dumb question but how do I find out how much AFMA my copy needs and how do go about figuring out how much I need to adjust?



YOu need to run it through some form of calibration check - I recommend FoCal as it really makes it very easy, especially if you have never done it before.

Have a look here http://www.reikan.co.uk/focalweb/


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## Invertalon (Jul 24, 2013)

My 24-70 II needs -3W and +1T.

My previous copy needed -2W and +1T (I returned due to decentered element).


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## scottkinfw (Jul 24, 2013)

W= 0
T= -2
For me, it is an amazing lens.


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## Skulker (Jul 24, 2013)

drjlo said:


> My copy of 24-70 f/2.8 II needs -9 at wide end and 0 at tele end on my 5D III. My Canon 70-200 f/2.8 II needs 0 at either end, and my 100L also needs 0. Some of my fast primes including 35L, 50L, 85L II range between -1 and -3.
> 
> A brand new Canon 17-40 f/4L I just borrowed needed -6 at wide and 0 at tele.
> 
> ...



As long as you can get it setup what does it matter. Some people seem to get so worked up about the number and dream up reasons to be unhappy.


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## drjlo (Jul 24, 2013)

Skulker said:


> drjlo said:
> 
> 
> > My copy of 24-70 f/2.8 II needs -9 at wide end and 0 at tele end on my 5D III. My Canon 70-200 f/2.8 II needs 0 at either end, and my 100L also needs 0. Some of my fast primes including 35L, 50L, 85L II range between -1 and -3.
> ...



A lot of the concern is due to future resale value, ease of sale given full disclosure, etc.


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## Skulker (Jul 24, 2013)

drjlo said:


> Skulker said:
> 
> 
> > drjlo said:
> ...



So you,re worried that someone else will be worried that a lens camera combo will be outside limits. Not much chance of that coming true due to manufacturing tolerances. I for one am very glad AFMA is on my camera.


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