[quote name='Class A' timestamp='1290859150' post='4494']
Do you know that's the real reason?
Maybe Pentax believes that moiré is rarely a problem for landscape photography (one of the primary applications for the 645D) and that users are craving for 100% crops that look crispish without any capture sharpening?[/quote]
No, but I know that most of fashion photographers use MF cameras and for some reason images with lots of high-frequency patterns (fabric textures, hair, etc) still manage to look ok.
[quote name='Class A' timestamp='1290859150' post='4494']I would never say such a thing and I wonder what makes you think I would? I only said that I don't know why companies like Leica and Kodak offer products without AA filters. Above I offer a speculation, but have no insights into the true reasons.
[/quote]
Well, you've quoted this: "But as long as uneducated photographers cry for a weak or no AA filter the industry will listen and give us dirty colors in fine textures. Thank's everybody.", haven't you?
[quote name='you2' timestamp='1290873235' post='4501']
Do you like the K5 relative to alternatives (7d, gh2, nex 5, nikon ?). I guess the question is a bit too broad since like is a very personal thing; do you think the rendering, colours, resolution, auto focus, dr are pretty much just as good; radically better, a lot worse or matter of personal preference (being different but neither better no worse)
[/quote]
Well, apart from the AA "issue I really like it. The AF is not quite as fast as on the 7D as far as I can see so far. However, the ISO performance is far better. Size-wise and in terms of build quality it is simply superb. No idea about color rendition yet but that's a RAW converter aspect and not so much camera-related. The DR will be interesting.
[quote name='Lomskij' timestamp='1290874807' post='4503']
No, but I know that most of fashion photographers use MF cameras and for some reason images with lots of high-frequency patterns (fabric textures, hair, etc) still manage to look ok.
[/quote]
If there are problems with moiré, shots are done again, probably by slightly changing the angle, distance, or slight defocusing. Elaborate post-processing might be another solution.
[quote name='Lomskij' timestamp='1290874807' post='4503']
Well, you've quoted this: "But as long as uneducated photographers cry for a weak or no AA filter the industry will listen and give us dirty colors in fine textures. Thank's everybody.", haven't you?
[/quote]
Yes, I quoted it. I didn't say it. I quoted it to illustrate that Falk doesn't agree that weak or no AA filters are a good idea. That doesn't mean that I know why the industry offers products with weak or no AA filters.
[quote name='Klaus' timestamp='1290864030' post='4497']
After the initial discussions with Falk this (aggressive post-sharpening) is obviously the fundamental difference in our positions.[/quote]
Can you please elaborate?
Do you not agree that capture sharpening is adequate and can restore detail to the extent the sensor is capable of recording?
The K-5's AA filter is not too strong, i.e., it doesn't destroy information that the sensor would have been able to record without it. This holds true for colour photography. Known B&W patterns are a different issue. I invited a discussion about this difference a couple of times, but so far without any success.
To summarise, don't you agree that regarding colour photography it is inadequate to call the K-5's AA filter "strong" or to speak of an "AA filter issue"?
To what extent the lack of an AA filter can help improve lens test and what the dangers might be in doing so, are interesting questions which, I think, should be explored.
That's a bit sad. Too bad the change of the filter is so expensive.
[quote name='Klaus' timestamp='1290878101' post='4504']
Well, apart from the AA "issue I really like it. The AF is not quite as fast as on the 7D as far as I can see so far. However, the ISO performance is far better. Size-wise and in terms of build quality it is simply superb. No idea about color rendition yet but that's a RAW converter aspect and not so much camera-related. The DR will be interesting.
[/quote]
Klaus sorry to bother you with this request:
You said the ISo of the k5 is far better than the 7D. What does this mean? is it better when both images are viewd at 100% or ist it still better when both images are printed the same size? I am saking because the 7d seems to resolve a bit more than the K5. This means one could use a bit more noise reduction on the 7d images to end up with the same Iq as the k5 (resolution and noise wide at least). Dr would be differnt though, I am imapiently waiting for your tests redarding this aspect.
11-28-2010, 04:12 PM
(This post was last modified: 11-28-2010, 05:10 PM by Klaus.)
[quote name='Class A' timestamp='1290949984' post='4517']
Can you please elaborate?
Do you not agree that capture sharpening is adequate and can restore detail to the extent the sensor is capable of recording?
The K-5's AA filter is not too strong, i.e., it doesn't destroy information that the sensor would have been able to record without it. This holds true for colour photography. Known B&W patterns are a different issue. I invited a discussion about this difference a couple of times, but so far without any success.
To summarise, don't you agree that regarding colour photography it is inadequate to call the K-5's AA filter "strong" or to speak of an "AA filter issue"?
To what extent the lack of an AA filter can help improve lens test and what the dangers might be in doing so, are interesting questions which, I think, should be explored.
[/quote]
I do not agree that a way-above-average capture sharpening should be applied to images used to measure lens performance. Frankly it is even debatable whether sharpening should be disabled for this purpose altogether (but then it has an impact on the scaling only). I believe that Imatest splits the different color channels for the slanted edge analysis so color artifacts are meaningless here (it works just fine with the M9 as mentioned) . It needs to do so to separate lateral CAs from the MTF analysis anyway (IMHO). That's all that counts for my application. As for the rest I don't overly care personally. Cameras come and go.
Whether post-sharpening is a valid approach for "field images" - again, that's a matter of taste. If you want to do it to recover details that's Ok for me and for the rest of the world. However, for my personal photography I don't require a strong AA filter. As mentioned diffraction serves as a natural AA filter from f/8 (APS-C, 16mp) and I'm mostly into ... handheld ... landscape/travel photography and I'm primarily using zoom lenses which are, for most of the image field, not sharp enough to cause serious problems. Frankly that's an average Joe's situation and not a science project. An AA filter will ultimately soften all images including those where diffraction has eliminated all relevant moiree problems anyway. Post sharpening will increase noise and produce sharpening artifacts. If the K5 would have the K7 noise characteristic aggressive post sharpening wouldn't really be an option at ISO 800, don't you think ? From my perspective this is not about one side or the other - it is about balancing all the negative effects based on your personal preferences.
And to answer your primary question - as of now I don't see the slightest indication that the K5 has a COMPARATIVELY weak AA filter (or RAW NR). You may debate whether "it's just right in conjunction with post-sharpening" (BTW, Pentax does not apply it to JPEGs - why ... ?) but I have to recognize that most other system cameras simply have a COMPARATIVELY weaker AA filter. Frankly, the discussion with Falk just reconfirmed my viewpoint here.
[quote name='jenbenn' timestamp='1290956909' post='4521']
Klaus sorry to bother you with this request:
You said the ISo of the k5 is far better than the 7D. What does this mean? is it better when both images are viewd at 100% or ist it still better when both images are printed the same size? I am saking because the 7d seems to resolve a bit more than the K5. This means one could use a bit more noise reduction on the 7d images to end up with the same Iq as the k5 (resolution and noise wide at least). Dr would be differnt though, I am imapiently waiting for your tests redarding this aspect.
[/quote]
If we look at the high ISO studio (not ideal) shots from dpreview, we do NOT see the K7 being "far better" than the 7D/D7000/60D, they all are very much the same (looked at 100% pixel level, which means we do magnify a bit more with the 7D and 60D).
What we do know about the high ISO from the K5 is that it gets some kind of filtering in the RAW data from ISO 3200 and up.
[quote name='Brightcolours' timestamp='1290961524' post='4528']
If we look at the high ISO studio (not ideal) shots from dpreview, we do NOT see the K7 being "far better" than the 7D/D7000/60D, they all are very much the same (looked at 100% pixel level, which means we do magnify a bit more with the 7D and 60D).[/quote]
Agreed. Keep in mind that they also all suffer from various DOF issues, which limit the usefulness of the test. I guess the only way to overcome this and still test the sensor to its maximum is to switch to 2D targets (e.g. something like the house poster than imaging-resource.com is using).
Quote:What we do know about the high ISO from the K5 is that it gets some kind of filtering in the RAW data from ISO 3200 and up.
In principle NR on RAW is a bad thing, but if the end result is still better than the competition then it can be forgiven. In my opinion a better way to evaluate the "end result" is to use several different RAW conversion applications (including the camera manufacturer own software), while putting some effort to customize the settings of each application to get the best image quality. Afterwards the best result from this group of images can be selected by comparing two images at a time, in a tournament-like process. This process should then be applied to RAW files from all the other cameras in order to get the best possible results that each camera can deliver.
The problem that remains with this approach is that image quality is still mostly a subjective affair, so “best†can be different for different people, but I still think that a comparison of images processed and selected this way would be more representative of how these cameras actually perform. The dpreview method of comparing images converted using ACR default settings is far easy to perform, but the results are of limited value. Small brands specifically (Pentax, Ricoh) suffer from lack of optimization by Adobe compared to the big two (possibly due to the use of DNG which encourages Adobe to be lazy).
My hunch is that even with the in-camera NR (RAW cookery), the K-5 high-ISO results would leave the 7D well behind, providing cleaner images that are also more detailed. However, I'm less certain about the D7000. It could be an interesting (though very time consuming) experiment. Any volunteers?
Klaus would you have preferred the K10D AA filter approach knowing that with 16.3mp there would be less of a problem anyway?
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