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Pictures not sharp


simon_damast

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<p>Hi, I have a Nikon D40x and for some reason my photos are not sharp.. I've tried everything.. changing aperture to increase depth of field, manually setting the ASA to 100, tried it on manual settings and auto etc etc.. but am not having luck. I suspect it is not the lense but the camera. Is there anything I can do to test / check and fix this error.<br>

Thanks</p>

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<p>Sorry not quite sure how to keep EXIF data in tact.. It was shot in large format so had to resize it to post to the web (I used photoshop) and reduced the image size to 20% of the original. Parts of the hair seem to be in focus but the focus was set on her eyes. ASA 100, aperture priority to try get depth of field.. nice medium aperture to keep shutter speed up<br>

Hope this helps</p>

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<p>Unfortunately, you have stripped some of that EXIF data off, but there's enough to go on for a start. First, you'll notice that her hair (on the left, which is the closest object to the camera) is actually quite clear. That's what you focused on. At 145mm, and with your lens just about as wide open as it can go (I'm assuming this a kit zoom lens, like a 55-200 or an 18-200?) you're not going to have much depth of field to work with. If you and/or your subject weren't perfectly still, and you were using single servo mode (where you lock focus before you shoot, as opposed to continuos focus mode), she or you could have drifted farther apart by an inch or so, making your in-focus area that much more shallow. Can't tell from the limited EXIF data whether you were using single or multiple AF points, etc.<br /><br />One of the great things about AF-S lenses is that you can have the camera AF, but then grab the focus ring and tweek a bit. That way when you see that it's focused on her hair, and not on her eyes, you can make up for that before releasing the shutter.<br /><br />What happens when you use a tripod and shoot a simple, static focus test object?</p>
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<p>Your image is out of focus. Focus is way off.<br>

The focus plain is in front of the face - you can see a few hair on the very left in focus and sharp.</p>

<p>Play around with manual focus and AF. Is there a beep to confirm focus in one of the settings? This can help in some situations.</p>

<p>Do you have the possibility in the D40 to select a focus point indicator in the viewfinder for AF and for the green light indicating focus is at that point OK?</p>

<p>I cannot see what the lens was from the exif data but in this particular case you might have been too close for the lens to focus. Check what the closest focus is for that lens at the particular zoom setting.</p>

<p>For further testing use a tripod if available and shoot a stable scene like houses with some depth and points of interest that are easy to focus on (take a note there) so one can detect if the focus plane of the sensor is what should be in focus.</p>

<p>I am certain we can figure this one out so do not despair :-)</p>

<p> </p>

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<p>That particular shot seems clearly to simply have the wrong part in focus. You might want to set your camera to focus on the center point only for those shots, and then focus there and re-compose. Alternatively, there could be something wrong with the camera or lens, but I doubt it. There's also a light spot on her hair and her face seems in darkness, so lighting is an issue, too.</p>

<p>And Matt, if he was using one of the cheaper lenses that are so prevalent with a camera like the D40, then he can't focus over-ride, you could break the camera or lens doing so, and the way the focus works on those lenses, manual focus is not so accurate anyway.</p>

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<p>Peter seems to be right in this particular case.</p>

<p>If the procedure suggested by Peter does not work, the focus of the camera and/or the lens should be off and then you would need to take or send the camera "and" the lens to the Nikon service for calibration.</p>

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<p>This is a typical situation where I easily get the same results as you... when I`m not extremely cautious.<br /> Don`t know if it is a crop; if not, given the magnification, you have almost no DoF. The slightest subject movement will change the plane of focus, making it an unfocused picture.<br /> The focus and recompose technique here use to fail easily. There is not only the possibility of subject movement (or should I say <em>the fact</em>, given that is a children!) but also your body movement when recomposing. If DoF is about a few millimeters, you need to be specially firm to keep your position.<br />As Matt wrote the EXIF info I see is FL 145mm, 1/320, f5.3. On a kit lens it could mean "wide open" given the focal lenght (I may be wrong). Don`t expect any lens to be optimal at it`s maximum aperture; obviously it`s not the cause here.</p>
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<p>The basic problem with close up photography is a razor thin depth-of-field, especially if you are shooting in natural light with the aperture open wide. If you are looking to get the whole face in focus, you may need to amplify the available light or use a flash. In the sample you can see the hair is in focus, but the face is not, so I don't believe the problem is with your camera.</p>
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<p>Size counts. For focus areas on the viewfinder, that is. The actual size may not be accurately reflected by visual guides in the viewfinder.</p>

<p>There are three focus points in the D40/x, and they are large compared to cameras which have many more focus points, but smaller in size. I sometimes ran into into similar problems with my D70s where the focus point covered more area than what I wanted the camera to focus on, such as a bird's head which only filled a portion of the focus area. So, sometimes the camera chose something else within the focus area on which to focus. The lesson took a while to sink in. The camera sensor could not read my mind.</p>

<p>'Assuming here that you have the 18-55mm DX lens which has manual and autofocus switches, but no manual override when autofocus is selected.</p>

<p>In this case, think about using manual focus where the desired focus object, one of her eyes, may also include something like her hair which is a closer distance to the camera. This can confound anyone if not checked on a magnified display. Just being aware of the possibility can help you avoid the situation recurring.</p>

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<p>I'm voting with John Tran on this one. Three large focus areas. If Simon was using all three, the hair was definitely selected by the sensor. Simon should check to see if he was using one or all three areas, and select only a single area, the center focus area. But, even the center area in this camera might have picked up the hair which is near the eye on the left since the areas are fairly large.</p>

<p>The EXIF does not contain the focus point datum in NX2, nor does the EXIF identify the lens used other than 145mm of focal length. Personally, I do not think the lens mattered much. It more likely is a focus sensor area issue, and how many of them were selected.</p>

<p>So, Simon, try using only one focus area for portraits to concentrate on a specific focus area of the subject, and then check the image enlarged. When in doubt, try the manual focus.</p>

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<p>The image is sharp. The depth of field is very narrow, a few millimeters at the distance of the hair in front of the face. By the time you get back to the eyes and more distant facial features, you have gone beyond the sharpness zone.</p>

<p>If you want the focus to be on the eyes and not the hair, you have to make sure that the autofocus focuses on the eyes. Another thing to try is a more forgiving f-stop such as f/8 or f/11. As long as this doesn't slow down the shutter speed too much, you should see more detail in more features because the smaller aperture will increase depth of field a bit.</p>

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<p>Thanks everyone... I took your advice changed the lens, shot a close of a page in a book from a tripod and it is sharp.... I suspect the problem is all of the above.... mainly DOF and possibly the camera focusing on the wrong part of the picture although I do have is set up for the centre focus area. Having the ASA at 100 and using a long lens I guess sucked all the light and although it was a bright sunny day I was forced to shoot wide open as I had a pretty high shutter speed for the kid. Lots of variables to think about in a millisecond moment.<br>

So I guess the question is now if I want a super crisp picture under these conditions I probably would have to push my ASA but would that in turn create grain and therefore not the crisp I am after?? I don't think changing the shutter speed is the answer and therefore the aperture wouldn't change.....<br>

PS can anyone tell me how to keep the EXIF in tact when reducing the picture size?<br>

Thanks All</p>

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<p>Keeping the EXIF data intact ... depends on the software you're using. You can always use Nikon's free View NX2, which allows you to quickly look at that info yourself, as well as export scaled-down JPGs from your RAW files with various cropping and tweaking as you see fit. <br /><br />As for the higher ISO impacting the quality of your image ... it's always a trade-off. I'd rather have a little bit of image noise than too little DoF or a sluggish shutter when I need a fast one. A tiny bit of noise/grain in a sharp image is a lot better than a clean and quiet image of an out of focus or motion-blurred subject. And don't forget: that noise might not be an issue at all, depending on how you'll be displaying or printing the results.</p>
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