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jsherman999 · 10-16-2008, 09:39 AM

Originally Posted by Wheatfield

Personally, I am in complete agreement, not that what I think really matters. Any thread with the subject line "Proof that the &^%$* lens doesn't suck" (or similar) is almost guaranteed to be a useless waste of bandwidth.

I disagree - I often just would like to see 'what could be done with a lens', vs.
raw pixel-level resluution numbers - those kinds og numbers are often available
on photozone and other sites anyway.

If we were to worry only about pixel-level resolution, bith the 77ltd and the
50-135 would be considered only above-average (according to photozone.)
As we've seen, they are not just above-average.

Originally Posted by Lowell Goudge

I think you are making too general a statement about "tests"

While I agree that it is virtually impossible to post photos that demonstrate absolute resolution of a lens and absolute IQ, there are a wide range of test photos that can show other aspects of lens performance that are not dependant on 100% pixle resolution, specifically but not limited to

- flair
- contrast (or lack of)
- focusing errors and flat field performance
- depth of feild and bokeh
- vignetting
- barrel and pincushion distortion
- exposure consistancy as a function of F-Stop
- chromatic aberrations and purple fringing

Additionally while not conclusive, resized photos that really "pop" right out of the camera with no PP still give an impression of image quality even though not down to the pixel level.

lets accept "test photos" for what they are. But just as an aside, I use a 22 inch monitor, in 1920 x 1200 mode. This means that at a pixlel level I can see 1/4 of my K10D image. If I view someone's image on my screen and it is sharp everywhere at this level of resolution, even though it may not be an absolute measure, it is bigger than most of us will ever print and pretty damm good!

Very well put, my sentiments exactly. I can see differences in IQ myself even in
resized images - I bought my 77, the Sigma 70, the 50-135, and the Tamron
28-75 and 70-200 based on images I saw here, at dpreview and elsewhere -
not on any resolution tests. And the 'pop' I saw in these posted images has been accurate and correct each time - when I received the lenses, my initial
impressions of the posted images have been 100% correct so far.

The 'lens doesn't suck' and club threads are invaluable, IMO.

.

10-16-2008, 09:39 AM	#13
jsherman999 Pentaxian Gallery Photos: 0 Posts: 3,431	Originally Posted by Wheatfield Personally, I am in complete agreement, not that what I think really matters. Any thread with the subject line "Proof that the &^%$* lens doesn't suck" (or similar) is almost guaranteed to be a useless waste of bandwidth. I disagree - I often just would like to see 'what could be done with a lens', vs. raw pixel-level resluution numbers - those kinds og numbers are often available on photozone and other sites anyway. If we were to worry only about pixel-level resolution, bith the 77ltd and the 50-135 would be considered only above-average (according to photozone.) As we've seen, they are not just above-average. Originally Posted by Lowell Goudge I think you are making too general a statement about "tests" While I agree that it is virtually impossible to post photos that demonstrate absolute resolution of a lens and absolute IQ, there are a wide range of test photos that can show other aspects of lens performance that are not dependant on 100% pixle resolution, specifically but not limited to - flair - contrast (or lack of) - focusing errors and flat field performance - depth of feild and bokeh - vignetting - barrel and pincushion distortion - exposure consistancy as a function of F-Stop - chromatic aberrations and purple fringing Additionally while not conclusive, resized photos that really "pop" right out of the camera with no PP still give an impression of image quality even though not down to the pixel level. lets accept "test photos" for what they are. But just as an aside, I use a 22 inch monitor, in 1920 x 1200 mode. This means that at a pixlel level I can see 1/4 of my K10D image. If I view someone's image on my screen and it is sharp everywhere at this level of resolution, even though it may not be an absolute measure, it is bigger than most of us will ever print and pretty damm good! Very well put, my sentiments exactly. I can see differences in IQ myself even in resized images - I bought my 77, the Sigma 70, the 50-135, and the Tamron 28-75 and 70-200 based on images I saw here, at dpreview and elsewhere - not on any resolution tests. And the 'pop' I saw in these posted images has been accurate and correct each time - when I received the lenses, my initial impressions of the posted images have been 100% correct so far. The 'lens doesn't suck' and club threads are invaluable, IMO. .