Hello.
This discussion was quite interesting to me, as I considered myself The Great Pixel Peeper (first of this name). I don’t consider myself an expert, but I know “this and that” about demosaicing, as I am the author of DCB (both, the method itself and referencee DCRAW implementation, but not RT implementation). Keepeng that in mind:
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Stairsteps artifacts of AMAZE may seem a big problem if the image is developed to emphasize them, and extreme sharpening artifacts are overlapping with demosaicing artifacts (they are there, that is true, noone is denying that).
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One can develop RAW in RT to hide this kind of problems. This reqires knowledge and skills. I attach my approach, as a proof that sharpened, AMAZEd image zoomed 400% can still look nearly artifact free.
_MG_1570.CR2.pp3 (9.9 KB)
In other words, there is nothing in presented pictures that shows any real problem with AMAZE (and I say that as someone whose algorithm is considered direct AMAZE competition). Remember You will get some strange artifacts everywhere if You sharpen strong enough (micronoise, highlight recovery artifacts, sharpening artifacts, differneces in CFA between pixels …)
NOW!
If we look at this discussion as purely academic pursuit of excellence:
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There is always DCB
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Correct CA before demosaicing as ALL demosaicing algos are prone to errors when R/G/B channels are not properly aligned. Automated CA correction solves some problems but demosaicing author should always be aware of this phenomenon.
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Right WB applied before demosaicing is also critical.
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As I mentioned, it is possible to try to apply DCB’s
remove overshooted pixelscode. I wonder if it would fix the prolem. Anyone care to try? -
If you really want to see image that shows demosaicing artifacts - feel free to use this one for testing. There is severe moire, wrong interpolation directions, stairsteps…
I hope I helped.
Jacek Gozdz <afjg.pl>