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Old Oct 7, 2007, 12:07 PM   #1
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The weather has broken and its no longer 100 degrees by 8am, so I ventured out this morning and did a small expirement. I have 3 lenses that could be called wide...
Pentax SMC DA 16-45/4.0 AF Wide Angle Telephoto Zoom Lens IMP
Pentax SMC DA 10-17/3.5-4.5 ED IF Fish-eye Zoom Lens
Pentax SMC DA 18-55/3.5-5.6 Zoom Lens
So I essentially have a 16, 17 and 18mm focal lengths available across 3 lens. A single mm should not make that much difference, so I took them out and across about 5 minutes took the same image, using the standard landscape program, aiming at the same point and standing in the same place. There was a tree off to my left, and I was standing in its shade. I should probably do it again, in full sun so that flaing and CA can be taken in to account (also did not use any hoods on any of the lenses). And yes SR was on.

Processed them from RAW to JPG using the Pentax supplied software, and then used IfanView to resize/resample them to 800x600 and then saved them eatch at 96% so as to meet Steve's 240K size limitation. Also the ISO speed was 200 for each.
Pentax SMC DA 16-45 @ 16mm 1/350 sec f11 Landscape mode
Pentax SMC DA 10-17 @ 17mm 1/180 sec f11 Landscape mode
Pentax SMC DA 18-55 @ 18mm 1/180 sec f11 Landscape mode
So here is the Pentax SMC DA 18-55 @ 18mm 1/180 sec f11 Landscape mode

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Old Oct 7, 2007, 12:08 PM   #2
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... and here is the Pentax SMC DA 16-45 @ 16mm 1/350 sec f11 Landscape mode
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Old Oct 7, 2007, 12:09 PM   #3
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... and finally the Pentax SMC DA 10-17 @ 17mm 1/180 sec f11 Landscape mode
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Old Oct 7, 2007, 12:29 PM   #4
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I thought it might also be helpful to crop an area, so I went back to the original jpg and attempted to crop the same area as closely as possible across all 3 images for a full resolution comparison. Then I saved each of them at 100%. These were all cropped at the center of the image, essentially I used the little buldge on the front side of the mountain just under the top as the main focus point, i.e., the red autofocus icon was attempted to be placed right over the same point for each image and that is what was cropped around....

Pentax SMC DA 18-55 @ 18mm 1/180 sec f11 Landscape mode

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Old Oct 7, 2007, 12:30 PM   #5
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Pentax SMC DA 16-45 @ 16mm 1/350 sec f11 Landscape mode

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Old Oct 7, 2007, 12:31 PM   #6
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Pentax SMC DA 10-17 @ 17mm 1/180 sec f11 Landscape mode

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Old Oct 7, 2007, 12:36 PM   #7
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So essentially compare away, especially between the kit lens (18-55) and its expensive brother - the 16-45, with the 10-17 fisheye thrown in for good measure.

enjoy! ....
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Old Oct 7, 2007, 12:48 PM   #8
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I decided to add a set of crops of the sides also. Used the same exacts points in the images to set the crop limits on, the lens thus determine the actual width and height of the crops. Saved the crops at 95% to meet the file size limits of Steve...

Pentax SMC DA 18-55 @ 18mm 1/180 sec f11 Landscape mode

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Old Oct 7, 2007, 12:49 PM   #9
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using the Pentax SMC DA 16-45 @ 16mm 1/350 sec f11 Landscape mode

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Old Oct 7, 2007, 12:49 PM   #10
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and the Pentax SMC DA 10-17 @ 17mm 1/180 sec f11 Landscape mode
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