Portrait taking problems

Hey guys. Over the weekend, I took a lot of shots of the extended family, and the only shots that are really lackluster are the portraits. I'm not sure if it's the lens, but when i shoot portraits at the wide end of the 17-55 2.8, I'm getting horribly unsharp pictures. I'm usually shooting at f/5.6 or smaller, shutter speed around 1/100. I'm using a speedlite 580II in ETTL mode. The room isn't all that bright, with only two or three lamps. The ISO is usually at 400. Could that be causing the lack of sharpness? I also mounted on a tripod and forgot to turn IS off.


The lens is sharp in most other cases, and I've never noticed a problem in any other shots. Even shots i've taken in really low light and slower shutter speeds are sharper. I've used zone AF and single point AF, and spot and evaluative metering, and nothing produces any area of sharpness. My main concern is that none of the shots with my other lenses (50mm 1.8 and 85mm 1.8) had any problems when shooting the same portrait.


This is a 100% crop of the zone AF area.. Shot at 18mm, f/6.3, 1/80s. ISO 400. Is the low-light while composing the problem?


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What camera do you use?


I doubt it should look like this at ISO 400 - even with a cheap lens as the 18-55, let alone with the great 17-55.


I don't want to tell you that it's the lens as I don't know enough yet. Maybe it is something you are doing wrong, I don't know.

I'm thinking it might be time for you to look into AF Microadjustment for that lens (assuming you're using a 50D/5D2/7D etc. body, which from your discussion of AF modes it seems like you are). The fact that you get sharp pics with other lenses and not this one (which is quite sharp) suggests an AF system issue to me.


Of course, I might just be suggesting AF Microadjustment because I just got a LensAlign Pro and am planning to test some lenses tonight. [:P]

Sorry, forgot to mention that I am using a 7D, amid all the other lens and shooting info...


I get sharp images with the lens when I'm shooting single subjects or landscapes, and haven't had any sharpness problems even when shooting with two wireless flashes at 18mm from a similar distance. The only variable is that with the group portraits, I'm using a tripod. Is it possible my cheap tripod is shaking a bit when the the shutter is released? I'm using a remote with a 2-second timer.


Of course, the other variable is my family. Maybe they're just not photogenic.

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Is the IS turned on while it is on the tripod? I think that can cause problems.
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The IS system on the EF-S 17-55mm f/2.8 is tripod-sensing, so unlike some older lenses (e.g. 300mm f/4L IS), it turns itself off when vibration falls below a certain level (which happens on a solid tripod). So, turning off IS is probably not the answer.


Shutter release on the 7D is very well-damped, so that shouldn't cause significant vibration - not to the degree of unsharpness you're seeing in the pic you posted.

It is difficult to say what the problem is but you can try to sort the problems one by one.


1. You mentioned that the lens is sharp in most other cases and that you never had a problem in any other shots. Does this count for all focal lenghts?


2. You used a tripod and the IS was left on. In Bryan&acute;s review of this lens he says:


This IS version is tripod sensing to prevent feedback loops between the IS sensor and stabilizer motor vibrations. The manual recommends turning IS off when tripod-mounting the lens (to save battery life) or when panning (panning mode IS is not available).


This could be the problem. I do not think movements from the tripod itself is the problem.


3. You said "when i shoot portraits at the wide end of the 17-55 2.8, I'm getting horribly unsharp pictures". Is this a problem only when shooting portraits or in general?


4. Is this a crop from the center of the image or from the side? If it is from the left or right side is the center sharp/in focus?


5. You were using a flash. Have you tried shooting the same portraits without the flash?





These are only a few thoughts. It is difficult to guess. I would have performed a few test with the camera on the tripod, no flash, IS off, plenty of light, using center focus point only and using different focal lengths. That will give you a clue if it is the lens or not.





- Johnny

If this was shot with a flash, I doubt the tripod or any other kind of shaking is the problem.


What program/mode is the camera set to (M, Av, Tv, Portrait etc.)??

The camera was in AV mode.


I'm going to try more shots using manual focus and then compare them to the AF shots. I'm beginning to worry it's the AF with either the camera or the lens.

Well it's not just AF IMO. The noise is too strong for ISO 400 on a 7D!

Keep in mind that it's not terribly uncommon for a certain lens/body combination to need a microfocus adjustment (that's why the option is included on newer cameras). I have a 70-200 f/2.8 L IS that requires a heavy MF adjustment on my 50D, yet no adjustment is required on my 7D.


When you set up a controlled test, make sure to do it at 100 ISO--you don't want noise (and itsautomatic removal) to skew your sharpness results.

Thanks for the tip, Sean. Is microfocusing adjustment particularly difficult/involved? Any way I could seriously screw up the lens? I have almost no familiarity with it beyond a vague understanding of what it is.


And thanks for all the suggestions. These forums have been invaluable for me the past year.

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Originally Posted by gbc

Thanks for the tip, Sean. Is microfocusing adjustment particularly difficult/involved? Any way I could seriously screw up the lens? I have almost no familiarity with it beyond a vague understanding of what it is.


And thanks for all the suggestions. These forums have been invaluable for me the past year.
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I'm sure there are optimal ways to do a MF adjustment and not-so-optimal ways. If you do it incorrectly, as far as I know, there's no risk of doing any damage to your lens and every adjustment is reversible (there might be damage to your reputation if you miss focus on every shot of a photographic session, however).


To dial in the MF adjustment on my 70-200, I set my camera on a tripod on one end of the largest room in my house (including a few feet of a hallway). I focused on my camera bag logo at an average portrait focal length and distance, and dialed in the MF adjustment until it was sharpest. After that, my keeper rate for the lens improved significantly. I haven't accessed the MF adjustment since.

It's not particularly hard, it seems. Before I got my fancy LensAlign tool, I used a [url="http://www.focustestchart.com/focus12.pdf]cut-out paper chart[/url]. With my T1i body (which lacks the microadjustment feature) and that chart, it seemed myEF 100mm f/2.8<span style="color: red;"]LMacro IS USM was front-focusing a bit, while all my other lenses were ok. But, there was nothing I could do about that myself - lens and body would have had to go to Canon Service. Now, with my 7D andLensAlign Pro, I just tested my100mm f/2.8<span style="color: red;"]LMacro, and pretty close (though I may adjust it a bit). The only other lens I've tested so far - my EF 85mm f/1.8 USM - seems to be back-focusing a bit. These are only single test shots, as well. I really need to shoot 3-5 shots, obviously. I haven't done adjustments yet (having a 2 year-old daughter means not having long blocks of time!), but the procedure seems to be simple.

Thanks for the help, guys. I tried a little microadjusting, and I think it may have solved the problem. Didn't have a whole lot of time to set up proper lighting or anything, but just from a quick test, the problem was apparent.


This is the lens prior to adjusting, at 18mm, from about 8 feet away:


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This is the adjustment at +10:


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(Glad I finally found a use for the bizarre, shiny string my girlfriend has lying around)


The problem is only apparent at wider focal lengths. Is that normal for this kind of problem? I've had this lens for a while, but most of my shots are around 40-55mm, so it took me a while to really notice the focusing problems. I also bought this lens refurbished. I figured that a refurbished lens would've been put through its paces, since it had to be repaired anyway, but I guess I should've checked it out better.


Anyway, thanks again everyone for the suggestions. I'll have to do more tweaking, but I think this is the right track. I can't thank you guys enough. I was really going crazy over this.

Check out that the long end is still sharp enough. If not, send the lens back I say.


Regarding the "+10", I believe it's normal. I gave a "-6" adjustment to my 17-85.

Looks better! I second Oren's recommendation - test again with the lens at a longer focal length. In a previous post on AF Microadjustment (AFMA), one person mentioned testing a 24-105mm f/4L and finding that it needed +5 at one end of the range, and -5 at the other end of the range - as a compromise, AFMA was left at 0. So, test at both ends of the range, and then find a compromise that works for you, probably weighted toward whichever part of the zoom range you tend to use more often.

So i've been struggling with this issue for a little while also... i havent tested this yet but i can already tell this is my problem with my 17-55... its just no longer sharp. I also use a 70-200 f/2.8 L thats sharp as a tack... thats how it was easy to tell my 17-55 between 17-25mm was having issues.


I have a 30D that apparently does not have AF MA... now what?

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Originally Posted by wusstigphoto

...thats how it was easy to tell my 17-55 between 17-25mm was having issues.


I have a 30D that apparently does not have AF MA... now what?

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Your only real option is to send the lens into Canon. Be aware that they may need to calibrate the body along with the lens. Good luck!