02-24-2011, 08:38 PM
[quote name='Rainer' timestamp='1298579287' post='6332']
You might want to reread the lenstip test ... just to cite them:
Lenstip: "It’s worth adding that its border performance should be rated very high.
Stopping down to F/4 causes the values to reach, or even go beyond
the level 30 lpmm, so it enables us to get really crisp images. "
So ... Lenstip does say: "beyond 30lpmm you get really crisp images" ...
Lenstip does not say "below 30lpmm performance is dismal"
With that, your questions should already be answered.
Just my 1ct ... Rainer
[/quote]
I'm sorry - to be clear I was paraphrasing. They don't call it dismal. That is not a quote.
But, nevertheless, they DO consider lenses tested on the Canon 20D that perform below 30lpmm "unusable".... and, in their test, the Tokina was tested on the Canon 20D.
From their FAQ:
"The oldest tests on the Optyczne.pl were performed on an 8-megapixel sensor of a Canon EOS 20D. In its case the best “primes†reach results near 45 lpmm and when you stop them down to f/16 the resolution decreases to the level a tad above 30 lpmm. That last value is deemed to be the decency borderline."
From their review of the Canon 18-55mm (also tested on the Canon 20D):
"at the maximum aperture, the Canon just exceeds the 30 lpmm decency"
Most tellingly, from their review of the Canon 15-85 (also tested on the Canon 20D):
"Usually, to acknowledge that the lens isn’t bad we require that it reach over 30 lpmm at the maximum aperture, and 40 lpmm at the sharpest apertures."
Edit: Just for the record, I hope this isn't something controversial. I'm just trying to rationalize the differences between the two review sites. Its clear to me that lens testing is complicated stuff - and I guess subtle changes in HOW you test can sometimes lead top opposite conclusions - both of which are based in truth. I guess I'm just looking for an expert's insight into all this. Thanks again for any help
You might want to reread the lenstip test ... just to cite them:
Lenstip: "It’s worth adding that its border performance should be rated very high.
Stopping down to F/4 causes the values to reach, or even go beyond
the level 30 lpmm, so it enables us to get really crisp images. "
So ... Lenstip does say: "beyond 30lpmm you get really crisp images" ...
Lenstip does not say "below 30lpmm performance is dismal"
With that, your questions should already be answered.
Just my 1ct ... Rainer
[/quote]
I'm sorry - to be clear I was paraphrasing. They don't call it dismal. That is not a quote.
But, nevertheless, they DO consider lenses tested on the Canon 20D that perform below 30lpmm "unusable".... and, in their test, the Tokina was tested on the Canon 20D.
From their FAQ:
"The oldest tests on the Optyczne.pl were performed on an 8-megapixel sensor of a Canon EOS 20D. In its case the best “primes†reach results near 45 lpmm and when you stop them down to f/16 the resolution decreases to the level a tad above 30 lpmm. That last value is deemed to be the decency borderline."
From their review of the Canon 18-55mm (also tested on the Canon 20D):
"at the maximum aperture, the Canon just exceeds the 30 lpmm decency"
Most tellingly, from their review of the Canon 15-85 (also tested on the Canon 20D):
"Usually, to acknowledge that the lens isn’t bad we require that it reach over 30 lpmm at the maximum aperture, and 40 lpmm at the sharpest apertures."
Edit: Just for the record, I hope this isn't something controversial. I'm just trying to rationalize the differences between the two review sites. Its clear to me that lens testing is complicated stuff - and I guess subtle changes in HOW you test can sometimes lead top opposite conclusions - both of which are based in truth. I guess I'm just looking for an expert's insight into all this. Thanks again for any help