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04-19-2010, 11:46 AM   #16
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I'm still getting used to the da 15mm. Coming from the 50-135mm where i tend to pixel peep every part of the image and find it tack sharp, unfortunately it's not the case for a 15mm wide lens. If i took an image of a person 5 feet away and try to pixel peep the image, i don't find that i get very good sharpness. Maybe because I'm trying to pixel peep something that is far away. The 15mm however seems to do excellent job on closeups. As for distortion, I noticed in a group picture, people on both ends of the photo get's distorted and stretched horizontally. I know it's something to expect from a wide lens, but according to the reviews i thought it would have less distortions then what I getting now.

Marc, have you done group shots with 15mm. How are you finding distortion on the either ends.


Last edited by Alex00; 04-19-2010 at 12:30 PM.
04-19-2010, 12:08 PM   #17
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I too hardly read reviews anymore, many of writers are so biased nowadays that I just want to try the equipment myself and make my own ruling. However, I know for a fact that this lens is a joy to use. When I went to Florida I stopped by a camera shop that had one is stock and he let me try it out on my K20D and it was an absolute joy to use. The lens was very sharp even wide open and the focal length was nice as well. If I had the money I would definitely buy one for landscape purposes as it would be the perfect lens. Unfortunately, the bills have to come first and they sure do like taking all your money away.
04-19-2010, 12:28 PM   #18
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QuoteOriginally posted by Tuner571 Quote
I too hardly read reviews anymore, many of writers are so biased nowadays that I just want to try the equipment myself and make my own ruling. However, I know for a fact that this lens is a joy to use. When I went to Florida I stopped by a camera shop that had one is stock and he let me try it out on my K20D and it was an absolute joy to use. The lens was very sharp even wide open and the focal length was nice as well. If I had the money I would definitely buy one for landscape purposes as it would be the perfect lens. Unfortunately, the bills have to come first and they sure do like taking all your money away.

Your right about those bills... this month my B&H bill from the USA was crippling
04-19-2010, 08:31 PM   #19
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The distortions on the side are not lens defects - it's simple perspective distortion, inherent in the whole note of taking a scene that's much wider than your computer monitor or a print viewed from a typical distance, and squeezing it to fit. Lens distortions would be on top of that, but indeed, the 15 has very little of that.

So don't put people on the very edges of the frame. Even in a little bit helps (then you can crop if you like). Here's an example where I cropped just slightly:



As for sharpness, it should be almost cruelly sharp in the center, even shooting wide open. Perhaps you could post samples you are not happy with?

04-20-2010, 02:40 AM   #20
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Correct me here if im wrong.
On the Photozone review it seems that the Sigma 10-20 @14 has better control of distortion than the DA15.
04-20-2010, 04:36 PM   #21
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I don't know how to read the numbers, but what one can tell just by lookng is that whatever distortion is present is in the opposite direction - barrel for the DA15, pincushion for the Sigma 10-20 @ 14mm. Both are good enough that it seems kind of pointless to worry about whatever small differences exist.
04-22-2010, 03:49 PM   #22
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Close up shots seems to be tack sharp almost macro like.

See image blow


As for little far away shots, I'm not sure anymore, I've been pixel peeping too much i can no longer tell what's sharp and what's not.

Check the image below and let me know what you think. Note image size is 6mb. I'm not focusing on anything specific, i just have the lens focused on 3ft at f8. The room size if about 20ft.

04-22-2010, 04:22 PM   #23
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QuoteOriginally posted by Alex00 Quote
I'm not focusing on anything specific
That's pretty much the problem right there. Something in that shot is in focus, but you have no idea what, so you don't even know where to pixel peep.

Don't listen to what some DOF calculator tells you "should" be in focus. Those calculations are assuming typical print sizes viewed from typical distance. Not 100% views on a computer monitor a foot from your face. In a 100% view, DOF is pretty much *always* thin. If you're going to pixel peep to judge sharpness, you need to pixel peep that spot where focus actually is.

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