Originally posted by Winder The 20% difference is probably due to the fact that the K-5 is a higher resolution camera. Comparing 16MP to 10MP. Everything else being equal you would expect the K-5 to show almost a 20% increase in resolution just because it has 60% more "pixels".
I selected a "specific" object because I don't have time to make a list of 50 other objects and I wanted an example. I was shooting with an Olympus E-3 before picking up a K-7 2 years ago. I know two people still using Olympus (E-5) and I have read numerous E-5 and K-5 reviews and compared them. I have not seen anything that indicates the K-5 has a lighter AA filter than my K-7. None of the comparisons between the K-5 and K-7 show any noticeable difference in resolving power. Images from the E-5 however do appear sharper in the reviews/test I have seen.
Maybe the difference is in focus, but if so that means all of the reviewers must be better at focusing the E-5 than the K-5. I'm not saying the K-5 is not a sharp camera. We are talking about 100% crops.
If you would, please post a link to a review or test that demonstrates the K-5's lighter AA and better resolving power.
Sorry, but I'll have to "fix" some of your numbers.
First, it's not "almost a 20% increase", it's over 20%, consistently shown in their own test. This alone is enough to prove there is a significant resolution increase by going from the K10D to the K-5.
Second, in this case we're talking about a test which measures the vertical resolving power, as line pairs per picture height. The difference between the K-5 and the K10D is less than 27.3%, and not 60%. Comparing the K-5 with the K-7 you'll only have a ~5.5% increase in vertical resolution so any real difference will be made by things like focussing and AA filter's strength.
Now, about the E-5 vs K-5: even on that specific zone, for that specific ISO I can't see the E-5 resolving more detail (not that a bottle label would be the best test target). It looks slightly, I mean very slightly better - but this can be explained by many other things like the compulsory NR, focusing differences, diffraction already playing it's part at f/9, different processing and so on; and also by the E-5's very light AA filter. By the way, DPReview had to re-do the K-5 tests over and over again, until they were able to get some acceptable focusing samples.
But, again, I claimed (and successfully proved) there is a significant increase in resolution by going from the K10D to the K-5; not that it have the lightest AA filter and I certainly wasn't comparing it to any other camera - I don't have to prove claims I haven't made