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Looking for maximum sharpness (lenses)


julie_a.

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<p>Having looked at the pictures and read thru the comments, I'll offer my own analysis. It appears that the point of focus was slightly forward of the eyes (a definite no-no because we perceive sharpness usually based on the eyes), it appears that depth of field was insufficient to encompass the entire facial structure sharply, or your post processing didn't apply enough of the sharpening tool. I agree with others that you probably weren't using the "sweet spot" aperture on your lens, and you were slightly off in focus, I didn't see subject movement, and honestly I think post processing sharpening could have solved most of your problem.</p>
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<p>William, I am now shooting with a new 7D. Will this change things?</p>

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<p>Yes and No.</p>

<p>No - for all the reason John Deerfield outlined – I agree with him.<br />Basically, the lens is the lens – a different camera is not going to fix or change the lens’s capacity or lack thereof.<br />Stop the lens down a bit and it will be sharper, on both cameras.</p>

<p>Yes - because using the 7D will allow you various leverages, to get more out of the lens.<br />As one simple example, for that particular shooting scenario instead of using ISO1600 if you were using the 7D, it has intermediate ISO settings, so you could have selected ISO 1000 and still used a slightly smaller Aperture (hence sharper), but NOT had to use 1/160s as the shutter speed - hence not be as worried about Subject Movement and or Camera Shake.</p>

<p>***</p>

<p>The bottom line is <strong><em>there are many things which could be happening in the image you selected</em></strong> and many people have commented upon lots of individual elements. <strong><em>Even if there is a little bit of each element, then the sharpness and the appearance of sharpness will be noticed.</em></strong></p>

<p>What I mean is - even at 1/320s at that close shooting distance you could have a little camera shake and more likely the girl could have moved slightly - the slowest Tv I have as my limit (if I can) is 1/400s for little kids to suppress subject movement . . .<br />I am not entirely convinced that the plane of sharp focus is on the lips – but Steven's comment prompted me to have another look and at really close analysis (of her dress) it does appear to be ever so slightly forward of the eyes: but that is really difficult to tell accurately and bet and money just looking at the low res image (for me at least) . . .<br /><br />But if the eyes are little out of focus, then that is another little element which makes the eyes that little bit softer when all the other issues are added together.</p>

<p>I still reckon that the <strong><em>major element</em></strong> of the soft look of the image is the inherent softness of the lens when used at F/5 (or F/5.6) at its longer Focal Lengths (i.e. 35 to 55). And I would address that first - remember that if the lens were used at F/7.1 or F/8, the DoF would also be increased and that is another factor which Steven also commented upon.</p>

<p><br />I have played with that lens quite a lot, the results of my in field tests, means I always strive to use the lens at F/7 to F/11, once I get wider than about FL = 22mm.<br />I shoot RAW + JPEG (L) and apply sharpening in post production, using the RAW file for serious work.<br />Correct Exposure & Sharpening Techniques are very important to extract the best from any lens and camera combination, also.<br>

My suggestion is have a re read of all the comments as I think that each has nailed a little bit of what is going wrong - and it is not just one issue.</p>

<p>WW</p>

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<p>I am familiar with this equipment. The Kit Lens will be the NON IS, version? At 40mm the aperture is wide open at F/5. The lighting in that particular image is soft / diffused on her face. (WW)</p>

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<p> and</p>

 

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<p>So then for a portrait, in order to have maximum sharpness, I would need more direct lighting? I really would prefer softer diffused lighting for portraits. I suppose this means I will sacrifice some of the sharpness then? (Julie)</p>

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<p>No.<br>

You should use the lighting you want - to make the statement that you want to make with it.</p>

<p>The point of my comment was, that:<br>

1. Your lens is soft at F/5 when used at 40mm<br>

2. The lighting on her face is soft / diffused.</p>

<p>The F/5 is a technical limitation: no matter what the quality of light is illuminating the subject.<br>

The soft lighting comment goes to “Apparent Sharpness” or the “Appearance of Sharpness” in the Image.</p>

<p>If the image is already soft due to the fact that the lens and that wide open aperture can’t make it super sharp (or if the eyes were behind the plane of focus) the softer lighting is going to make that softness appear MORE soft – if you get my gist.</p>

<p>***</p>

<p>An afterthought:</p>

<p>Maybe comparing these two examples of mine, using the same lens, might assist to explain why I think there are a combination of issues you are facing AND those issues are accumulating to make some of your images soft and also appear soft:<br>

This image is taken with the 50/1.4, it was shot using the lens at F/1.6: <a href="../photo/9567754&size=lg">http://www.photo.net/photo/9567754&size=lg</a><br>

Her eyes are NOT sharp; they are just behind the plane of sharp focus; the DoF is very narrow; I shot it hand held; it was shot at ISO3200; she was moving; the Shutter Speed was 1/50s –and it was late at night perhaps I was tired and I moved a bit; the lighting is from softish diffuse room lights; the picture is grainy . . . overall the picture looks NOT that razor sharp.</p>

<p>This image was taken with the same lens and the lens was used wide open at F/1.4: <a href="../photo/11468622&size=lg">http://www.photo.net/photo/11468622&size=lg</a><br>

His eyeball is pretty sharp: - <a href="../photo/11468625&size=lg">http://www.photo.net/photo/11468625&size=lg</a><br>

But: the lighting is direct and hard; I used a tripod and remote release; ISO200; ET was very still; I used Manual Focus and Triple Checked it . . . etc</p>

<p>WW</p>

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<p>Don't shoot at high ISO (1600) when it's not necessary to boost your shutter speed. You could have made this shot at ISO 400 without too much concern regarding camera shake.</p>

<p>Make certain that you focus exactly on the nearer eye.</p>

<p>Learn how to sharpen in Photoshop or another post-processing program. Photoshop's Smart Sharpen feature is very nice.</p>

<p>Limit the effects of camera shake with tripods, monopods, Image Stabilization (IS) lenses, a cable release, and mirror lock up if available.</p>

<p>Use strobes (flash) when applicable.</p>

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<p>Thanks everyone for your help. I will start looking at all the suggestions of possible issues now and tackle one by one. All the input has been tremendously helpful.<br>

Dan, the mask you applied to my image made quite a difference, thank you for trying that. I am still learning photoshop and really haven't tried anything at all with sharpening yet (mostly using for color/contrast adjustment, playing with curves to achieve the color I'd like, etc).I will be sure to try learning this next.</p>

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<p>Ansel Adams himself, used to teach: never hand holding any camera slower than 1/250th of a second. The "old rule of thumb" about shutter speed should equal focal length, is just that, an old rule. Camera shake is a very real problem. There is an old adage that "your tripod, is your sharpest lens".</p>

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<p>It's worth noting that Adams didn't have IS or VR in his day. The rules have changed.</p>

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