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Old Sep 13, 2006, 6:31 PM   #1
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http://www.steves-digicams.com/2006_...s/IMGP0236.JPG

What went wrong with that image? The whole left side is totally blurred. Defective lens/camera? Its not a depth of field problem.

It looks worse than those from cheap P&S cameras.
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Old Sep 13, 2006, 7:42 PM   #2
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Looks okay on my display. Perhaps you have a defective monitor? (No offense intended.)
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Old Sep 13, 2006, 8:14 PM   #3
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Looks good on mine also!
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Old Sep 13, 2006, 11:11 PM   #4
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Guys, the left side of the image is blurry. The telephone pole is blurry, but the bricks are sharp. The no parkingsign is sharp.

Maybe the lens is bad...?
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Old Sep 14, 2006, 12:21 AM   #5
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Oh yeah! Now I see it. I wasn't looking far enough over to the left end of the photo. I'll check out the other photos also.
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Old Sep 14, 2006, 12:35 AM   #6
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There's no telling about people's taste...or eyesight...or monitors. :-)

Some people might make the mistake of allowing their browser to *sharpen* the photo by resizing it *downward* to "fit the panel."

But I viewed it as I think the original poster intended: 100% crop. :G

So for the blurry-eyed, look at this D-50 pic by Steve. Notice the sharpness of the detail "down the street" on the left side (at 100% crop). This D50 lens was sharp:

http://www.steves-digicams.com/2005_...s/DSC_0126.JPG

And this one K-100d lensis massively blurred!

http://www.steves-digicams.com/2006_...s/IMGP0236.JPG

This next ist* DL shot is not as sharp as the D-50, but I'm assuming it is the "same" Pentax lens model as the previous shot.

http://www.steves-digicams.com/2006_...s/IMGP0137.JPG

This fortuitous 2004 shot from the ist* DS demonstartes that the depth of fieldon the left side of the picture is *different* than the depth of field in the center. That my judgement. (The passing trailer adds a near element that's missing in the others for looking at what is happening.)

http://www.steves-digicams.com/2004_...s/IMGP0686.JPG

The focus is "near" throughout, but the depth of field is remarkably deep in the center conpared to the detailed left side.

What do you think? Is this Pentax kit lens about as good as a pinhole camera? (I own a ist* DL with this same lens.) :?
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Old Sep 14, 2006, 4:55 AM   #7
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The D50 image looks great, there has to be some kind of defect with the K100 camera/ lens used for these samples. That particular image is probably the worst sample i've seen come from any DSLR.
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Old Sep 15, 2006, 4:29 AM   #8
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Oddly, this image also taken with the 18-55 kit lens doesnt seem to show the same amount of blurring as the other shot.

http://www.steves-digicams.com/2006_...s/IMGP0249.JPG
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Old Sep 15, 2006, 5:53 AM   #9
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Another explanation - How about camera shake at the end (or beginning) of the shutter run? This assume the shutter runs horizontally.

RG
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Old Sep 15, 2006, 9:41 AM   #10
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beethovenspiano wrote:
Quote:
http://www.steves-digicams.com/2006_...s/IMGP0236.JPG

What went wrong with that image? The whole left side is totally blurred. Defective lens/camera? Its not a depth of field problem.

It looks worse than those from cheap P&S cameras.
It is not something that really new (but still weird) and I have seen this many times before for Pentax DSLRs. The first time I can see is the *ist D samples at Dpreview more than two years ago. At that time, when I pointed out the strange phenomenon to guys, I was often bashed.

Now, after I have used Pentax DSLRs of different units and different models for tens of months, I know what's the reason for this. It is very simple, the focus plane is not flat and not symmetric enough (usually a lens problem, but then there is no ideal/perfect optics on this planet) and the sensor plane is not absolutely perpendicular to the lens' optical axis. Things will becomes even worst for de-centred CCD alignment.

So, that's why alignment is *always* very important and that's what I have been emphasizing, despite some particular people don't like what I say (just for the sake of brand loyalty). For how I measure the alignments of my K100D, see:-

http://www.geocities.com/ricehigh/K1...ll_Review.html

Well, my K100D's alignments seem fine for all those critical things. The projected AF red dots are off and asymmetrical, though.

Lastly, to minimize the problem you see, you a prime lens. Those wobble cheapo zoom lenses are usually the culprit.

RiceHigh
http://www.geocities.com/ricehigh
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