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Old Jan 15, 2007, 8:26 PM   #1
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Hello. I've posted here in the past, but haven't been here in a long while. This is about the only place that has a designated 'Minolta' section, so I thought I'd mention this here before I send my camera off for repair to see if anyone has had any similar problems.

I have a Minolta Maxxum 7D. I know my camera very well... and I did question some focus problems in the beginning, but learned a bit more about my focus area options and soon discovered the problem was me. Since then, I've learned a great deal more about photography (especially outdoor/nature photography) and I've recently become interested in portrait photography andam currently working on a studio set-up in my basement. Anyway, my point in all that is to say that I know enough about my camera now to understand that I really do have some focusing issues for certain now.

To sum it up, let's say I want to take 3 shots of the same subject all with the same settings/focal length. I focus and snap the first shot... unfortunately, I can't just snap thenext shotrightawayor it will more than likely be very soft. Instead, I have to move the camera and focus on something else nearby, then return to the subject and re-focus andtake the second shot. Then I have to do the same for the 3rd shot. I have to do this between all my shots or I end up with a lot of very soft shots that are not well-focused. This gets quite annoying in the studio when I have to focus on the wall behind the backdrop between every shot of the subject. Does anyone else have this problem?

Another issue is probably separate from the above mentioned, but I'llbring it uphere as well. OnAperture Priority, it won't allow me to open it up all the way tof/1.4 under very poor lighting conditions.The focus light flashes to tell me it's beyond the camera's capabilities.For instance, I helped a friend take shots ofa band competition... I wason top of thepress box using my 85mm f/1.4 lens on AP mode.From that distance (after dark, with football stadium lights),it wouldn't allow me to open upwider thanf/2(or it might have be 2.8... I forget exactly). I've noticed this several times when I have the camera set on AP mode. Any reasons why this occurs?

Now, if I sendthis to Sony for repair... does anyone know how longI should expect this to take? Anyone sent their camera to Sonyforrepair yet?
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Old Jan 16, 2007, 12:00 AM   #2
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MANUAL FOCUS IS A WONDERFULL THING
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Old Jan 16, 2007, 6:06 AM   #3
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gracie328 wrote:
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Now, if I sendthis to Sony for repair... does anyone know how longI should expect this to take? Anyone sent their camera to Sonyforrepair yet?
Precision Camera, who handles KM repairs in the US, either turns them aorund in a few days, or in a week or two if parts are on backorder. I would advise getting the cmaera in ASAP rather than waiting. You can submit your warranty repair order online. Wrap a copy of your invoice around the camera and put a second copy in the box. Don't send anything you don't have to. I took the hot shoe cover off, and only sent the body and body cap.

http://www.precisioncamera.com/


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Old Jan 16, 2007, 7:35 AM   #4
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MANUAL FOCUS IS A WONDERFULL THING
I fully agree... however, this problem didn't use to exist... and yes, I could use manual focus, only that wouldn't 'fix' the problem, but only avoid it. When the AF functions as it should, then I may choose to use MF at times as well, but when there is a quite obvious problem, then I want it fixed.

Thanks for the info on Precision Camera.
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Old Jan 16, 2007, 9:26 AM   #5
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gracie328 wrote:
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To sum it up, let's say I want to take 3 shots of the same subject all with the same settings/focal length. I focus and snap the first shot... unfortunately, I can't just snap thenext shotrightawayor it will more than likely be very soft.
Are you getting focus lock when you half press the shutter button? What are you focusing on (eyes, body, etc.)?

At wider apertures, you will have a very shallow depth of field. For example, if you're trying to take a head shot of someone, one eye may be in focus and the other not in focus at wider aperture settings, because DOF gets pretty thin (especially with a lens like your 85mm f/1.4).

See this Depth of Field Calculator:

http://www.dofmaster.com/dofjs.html

So, if you're framing tight, you have to be very careful of your focus point. Make sure you don't lean any after locking focus either (as that can throw your focus off).

I try to use the focus point closest to my subject's eyes instead (especially since if you focus on a subject's body, the eyes and face may be out of focus at closer ranges and wider apertures, even without any reframing). Reframing too much can also cause backfocus if you're framing tight at wider apertures.

Here are two different articles on this subject:

http://www.mhohner.de/recompose.php?lang=e

http://www.outbackphoto.com/workshop...y06/essay.html

Chances are, it's you causing the issues (focusing on body versus eyes, etc.). But, check your Autofocus Accuracy, too. I use books on a table staggered at different ranges to the camera for this purpose. Some cameras do have AF calibration issues. See this thread for details.

http://www.stevesforums.com/forums/view_topic.php?id=107395&forum_id=84

If you do have a backfocus or frontfocus issue, Precision can recalibrate it for you. But, chances are, it's technique.

Make sure you're not seeing blur from camera shake or subject movement, too. Are your shutter speeds fast enough in the lighting you're trying to shoot in?

Quote:
Another issue is probably separate from the above mentioned, but I'llbring it uphere as well. OnAperture Priority, it won't allow me to open it up all the way tof/1.4 under very poor lighting conditions.
The camera will always focus with the aperture wide open. So, setting it to a wider value won't improve the ability for the camera to focus in lower light. The aperture is only closed down to your desired settings at the time you take the photo.

Quote:
The focus light flashes to tell me it's beyond the camera's capabilities.
It sounds like you need more light. I'd also remove any filters you have on the lens to make sure a filter isn't causing an issue. For darn sure, don't keep a polarizer on a lens in low light (since you'll typically lose around 2 stops of light with one on the camera).

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For instance, I helped a friend take shots ofa band competition... I wason top of thepress box using my 85mm f/1.4 lens on AP mode.From that distance (after dark, with football stadium lights),it wouldn't allow me to open upwider thanf/2 (or it might have be 2.8... I forget exactly). I've noticed this several times when I have the camera set on AP mode. Any reasons why this occurs?
If you have the exposure compensation dial on 1/2 (0.5) stop increments, it may not allow you to shoot with the aperture fully open with many lenses. You need to use the 1/3 stop increments side of the dial instead if you want to open the aperture up all the way.

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Old Jan 16, 2007, 12:58 PM   #6
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:sad:I knew I'd get this response... I guess that's why I've hesitated asking the question. It's not me. Notice I said 2 yrs ago... it was me (I didn't understand the focus area and I was still learning about DOF)... but since I learned about that,the camera has worked well and I NEVER had to do what I'm doing now. And even now, as long as I focus on something else other than the subject and then 're-focus' on the subject, I can still get a sharp focus with the AF... but the AF won't focus properly for more than one shot.

It happens when I focus on flowers, birds, people in my studio... ABSOLUTELY EVERYTHING. And I do understand the DOF... it's not a DOF issue... I'm shooting in studio at f/11 and f/13 and I've even shot with a smaller aperture than that and it still does it. But even on a flower with a wider aperture, I shouldn't be able to get one sharp shot and without altering any settings, the next is very soft or just plain OOF... but if I move and focus on something else, then come back (settings and distance still the same), then the next shot will again focus sharp. I'm shooting with my Minolta 85mm f/1.4 lens which is probably the sharpest lens I own... and it happens when I'm doing a head shot, full torso shot, full body shot... EVERYTHING. If it was me, it wouldn't correct itself with simply focusing elsewhere, then re-focusing on the subject. BTW, I ALWAYS use a tripod.

As far as the aperture priority, I said that wasn't related to the focus problem... I'm sure it's a totally different issue. The stadium was extremely well lit. My friend's camera (a Canon) will open up to f/1.4 and focuswithout any problems... but mine wouldn'tfocus beyond f/2 or 2.8. It really shouldn't have needed more light in this situation. I've seen this happen before in other situations where it shouldn't happen. The only filter I had on was a UV to protect the lens. Should I have taken it off? I wasn't using theexposure compensation atall at the time.
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Old Jan 16, 2007, 1:18 PM   #7
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gracie328 wrote:
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:sad: And even now, as long as I focus on something else other than the subject and then 're-focus' on the subject, I can still get a sharp focus with the AF... but the AF won't focus properly for more than one shot.
That's odd (focuses for one shot only). lol

Try remounting your lens in case it's something like dirty contacts causing it. I'd also click the AF/MF switch up and down a few times to make sure a bit of oxidation under a switch isn't causing it, too. Ditto for using all other buttons (in case one is sticking a bit somewhere causing an issue).

You may also want to reset everything back to factory defaults (you'll find a couple of different reset choices in the menus). You may have it setup for DMF (switches automatically to manual focus after a AF lock) or something causing the issue. So, resetting it back to factory defaults would probably solve anything setting related.

Again, I'd check AF accuracy to make sure it's calibrated properly too (see the thread I posted a link to in my last post for some discussion on AF calibration). They can recalibrate it if it's off.

Is it only with the 85mm? It could be a lens issue, too.

Quote:
The only filter I had on was a UV to protect the lens. Should I have taken it off? I wasn't using theexposure compensation atall at the time.
Well, that's up to you. But, filters can cause flare with some scenes, which could impact your AF accuracy. If it's a good quality UV filter, that's probably not the issue.

As for Exposure Compensation dial, I'm not sure if it makes any difference if you have Exposure Compensation set or not in order to open up the aperture all the way with some lenses.

You've got a 0 (no compensation) setting on both sides of the dial (the yellow/orange side is for 1/3 stop increments, and the silver/gray side is 1/2 stop increments).

But, I have seen it reported that you must keep the dial on 1/3 stop increments side in order to open up the aperture all the way with some lenses.

So, you may want to check it to see what side of the dial you're using. If it's on the 0.5 increments side of the dial, try rotating it around to the 0.3 increments side of the dial (the yellow/orange scale). It should be pretty easy to check to see if that's your issue (try it both ways and see if you can select a wider aperture or not).


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Old Jan 17, 2007, 2:13 PM   #8
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Thanks. I have been using the 1/3 stop increments on the EV dial.
Quote:
Is it only with the 85mm? It could be a lens issue, too.



No... it's with all my lenses. I have two GOOD lenses and two kit lenses... the two good ones are the 85mm f/1.4 which was purchased new and then a 200mm APO G lens which was purchases used. Both are REALLY sharp when theyfocus properly... but if I don't focus on something else in between shots, then I get really soft to OOF shots. It does make an attempt to focus and the focus light SHOWS that it is focused... but obviously, it's not focused properly. But all I have to do is focus on something else and come back to it and focus and snap and more than likely, I'll get a good shot unless I do make a mistake myself that screws it up.

Now that I thinkabout it, I didn't really even explain this accurately. Idon't actually even have to 'focus' on something else... I just have to make sure that I "get the subjectOOF"... thenbring it back into focus and snap. But I can't focus on the subject and snap... then snap another from that point... I have to 'de-focus' first (if that's a word)... then come back and snap again. Same thing only I'm not literallyfocusing onsomething else in between.

My UVfilter is either aHoya or a Tiffen... can't remember which.

I may try resetting everything back to factory defaults and start from there and see what happens. Thanks forall thesuggestions.
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Old Jan 17, 2007, 5:04 PM   #9
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I'd check it for backfocus or frontfocus (see the thread I posted a link to in my first reply to this thread for a discussion on a couple of ways to check it).

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Old Jan 17, 2007, 8:07 PM   #10
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Just a couple thoughts......On the front of the 7d is the focus selector, I wonder if yours is set to 'c' (continuous focus) or S (single frame focus). C mode may even work better than reframing, though you'd still be sacrificing the time it takes to confirm focus lock.It should spend most of its time in A (auto)I'd likely send mine in if I was experiencing similar issues.

I guess it is possible that dirty contacts or a malfunctioning lens could cause such a problem, but I've never experienced any wierd problems from either ( the body would think no lens was attached). Cleaning the contacts and confirming the issue with more than 2 lenses would be enough to convince methat it was my body.

On the issue of aperture selection, my 7d will allow me to select f1.7 (on my 50mm f1.7) in an unlit room with the lens cap on. It doesn't force any aperture or lock out any aperture range, or at least I cannot reproduce your results. I even reconfirmed this at ISO 100. It doesn't restrict f values at all, I can select any aperture from f1.7--22. The shutter will even release at f22 (though I've maxxed out the shutter timer at f2) I can confirm that this issue isn't present in my 7d, but can only guess as to why it presents in yours. Are you using zone matching?

Have you tried a reset of the camera? sometimes software glitches turn up some pretty strange bugs. A reset should correct any of those.
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