# 7D - I'm goin' nuts with focus



## CharlieB (Oct 25, 2012)

Got a 7D. New.

It came with 2.0.3 - but I'm not going to blame the firmware.

I like to shoot fast lenses, and shoot them close to, or at wide open.

28/1.8 at f/2 - close distance - five feet or so... backfocus. At 30 feet - front focus.
50/1.4 at f/2 - same thing
100/2.8 macro - same thing

I'm talking a shift of "-7" at close distance, to +4 at further distances, and +9 at close to infinity distances (300 feet or so).

I'm basically... going nuts here.


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## CharlieB (Oct 25, 2012)

Should also say, the 5DmkII is not having a problem with those lenses. I have - 3 set on the 50, 0 on the 28, and 0 on the 100, and they track linearly close to far.

This has got to be a body issue.


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## Mt Spokane Photography (Oct 25, 2012)

Typically, at distances near mfd, lens AF changes. However, 5 ft with a 28mm lens should not change that much.
It should not be that bad for three lenses.


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## CharlieB (Oct 25, 2012)

Just tested live view... focus perfect, of course.

I better call Canon tomorrow


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## neuroanatomist (Oct 25, 2012)

My 100L Macro on my 7D was +1 near the MFD, +3 at 8 feet, and +2 at 16 feet. 

I agree - call Canon.


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## CharlieB (Oct 25, 2012)

were they able to correct?


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## K3nt (Oct 25, 2012)

Don't go nuts, it tends to distract from the rest of your life. ;D

When I got my 7D, at first I didn't notice, but slowly as I expanded with more lenses I noticed the focus was off. Took the whole lot in to the service center and they calibrated all of it in a few days and it's been perfect ever since, now if I miss a shot it is due to my own clumsiness and not that the camera wouldn't work.


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## CharlieB (Oct 25, 2012)

One more test... tonight.

I don't want Canon to touch the lenses, they've never had an issue on other bodies, including my 5DmkII.

Just the 7D body - is nutz. Or I'm nutz


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## ck5dmkiii (Oct 25, 2012)

My 7D had a world of problems with my 50L and 70-200 2.8II I previously owned. I went crazy trying to figure out the issue. Ended up sending it to Canon a few times with all my lenses to get it sorted out. Good luck and hope it works out


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## ishdakuteb (Oct 25, 2012)

don't have the other two lenses, but i do not have problem with my 50mm f/1.4 with my 7d, even on my 30d. have not yet tried to put it on 5d iii...


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## marek.sykora (Oct 25, 2012)

I own 7D since April, before I had 30D and before analog 33. I own 20/2.8, 28/1.8 and 85/1.8 all time.

- in analog ages I considered 85 is superb, 20 and 28 great
- in 30D ages 85 was superb, 20 still great but 28 was average/poor, esp. at low apertures

Before microadjustment all my lenses was worse on 7D than on 30D.

After MA:

- 85 is superb at f/2.2 - f/11, I can see poor quality wide open and also f/16+ due diffraction
- 28 is superb at f/2.2 - f/5.6 on near distances, wow, but still average/poor on infinity
- 20 is poor until f/4 in all distances, average at f/5.6 - f/11

7D is great, but all my lenses need MA around -8. I didn't find how to set 28/1.8 to be great on infinity, I guess it's not designed to be landspace lens, but low-light street/portret photo. I love my 28/1.8 since having 7D and MA.

I think my lenses are quite old, I tried 17-55/2.8 for two days and I was so suprised how good is the zoom both in IQ and AF accurance/speed terms.


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## CharlieB (Oct 27, 2012)

Might have gotten it fixed.

The 28/1.8 was goin' bonkers, and my other lenses were not immediately available.....

Well, the 28/1.8 finally quit completely. Refused to focus. Remounted the lens. Nada. Cleaned contacts on lens and body, and... it started focusing, AND focusing pretty well too.

Tonite, it seems to like a -2. All the lenses seem to like -2, except the 100/2.8USM which I haven't tested yet, and the 24-105 which likes a +2. 

But... IMPORTANTLY, it seems like the linearity of things has settled down considerably. I had some issues with the 5DmkII as well... contacts not right, causing problems in operation. That cleared up with a little use. I guess the 7D needed some help.

I'm still testing. I need some daylight to really give it a proper test.... more tomorrow.


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## CharlieB (Oct 29, 2012)

*7D "driving me nuts" -- more to it!!!!*

So, the 7D is fine.

This is what I have found out, and I'd have not guessed this in a million years.

IF I pull the CF card, or IF I power down, and I DON'T use the 28mm/1.8, the 50/1.4 and 100/2.8USM are fine, as also are the slower zooms.

BUT

IF I mount the 28/1.8 it works like crap, and if I mount the 50/1.4 or 100/2.8USM after that without powering down or pulling the card (which powers down), the 28/1.8 sours the focus system for the other lenses, throwing their "linearity" from close to far, all to hell.

So.. .how in the heck am I gonna explain, and convince Canon about THAT problem.... 

I tested this on my 5DmkII, and the same thing happens. Its a poison lens.... that 28/1.8.

Funny it worked GREAT on my 400D

I gotta think on this a bit... may be better to just get a new lens.


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