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08-01-2011, 08:36 AM   #31
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QuoteOriginally posted by normhead Quote
Funny, I sold two prints this weekend taken with a point and shoot. One , printed as a 20x30 canvas.. was taken with my old 5 Mp Optio10... not one person complained about the lack of sharpness. Weird, those people need to read Pentax forum more.
And Chevy sold over a million Chevettes!

Seriously, though, I'm sure you did a fine job with those photos - we'd love to see them!

08-01-2011, 08:41 AM   #32
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QuoteOriginally posted by civiletti Quote
As I wrote, most other optical imperfections can be overcome or at least ameliorated in post production. It's tough to add info that is not in the image. The higher the resolution of the sensor becomes, the more MTF50 of the lens matters. Your point about sample variation is valid. PZ's retest of the DA21 is consistent with results on the k-10, though. Did they use the same copy?
Things like correcting lens flare can be time-consuming or nigh impossible. PF and CA, while able to be ameliorated, cannot reliably be eliminated without loss of detail. Corrected barrel or perspective distortion usually results in a reduction of image; for example, a photo taken with an 18mm lens corrected for barrel distortion can result in the same FOV as a 21mm lens w/o correction.
08-01-2011, 08:43 AM   #33
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QuoteOriginally posted by civiletti Quote
And autos are about rolling, and loudspeakers about sound, and wine about alcohol, but folks pay a lot of attention to small variations in their performance, not without good reason I think.
Autos are about much more than rolling. Stopping, for instance.

"Sound" is so complex and nuanced, you may as well say a lens is about photography.

Wine is about alcohol? You must be an a Philistine, an alky, or on the wagon!
08-01-2011, 08:45 AM   #34
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QuoteOriginally posted by stanic Quote
I just looked at the review of 21/3,2 on SLRgear, and what it says about sharpness is quite reassuring: "The 21mm /3.2 AL is a very sharp lens. When set to an aperture of less than /22, the lens didn't register much more than 1.5 blur units on our sharpness chart. I would put the optimal usage at /8, where image sharpness is tack-sharp across the whole frame. At /22, image softness ''degrades,'' probably due to diffraction limiting, to 2 blur units. All in all, excellent performance."
Pentax Lens: Primes - Pentax 21mm f/3.2 Limited SMC P-DA (Tested) - SLRgear.com!

do you think they are able to cope with the field curvature in their test or is this sample variation?
I don't know what a "blur unit" is, and I don't know how their methodology differs from Photozone's, but I do know that the DA 21 is good enough for me!

08-01-2011, 09:09 AM   #35
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QuoteOriginally posted by luftfluss Quote
Autos are about much more than rolling. Stopping, for instance.

"Sound" is so complex and nuanced, you may as well say a lens is about photography.

Wine is about alcohol? You must be an a Philistine, an alky, or on the wagon!
I think that was exactly civiletti's point.
08-03-2011, 04:07 PM   #36
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QuoteOriginally posted by luftfluss Quote
"Sound" is so complex and nuanced....

Light is not?
08-03-2011, 10:32 PM   #37
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QuoteOriginally posted by civiletti Quote
Light is not?
WAVES are complicated!!!
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