rectangular shaped noise in d90

[iremaltan]

<p>Okay, I had posted a similar question in the Nikon category of the forums thinking that d90's image processing software was the problem. I discovered that it's actually adobe camera raw 4. I have the same photo that is shot at iso 640 in three versions, raw converted in raw therapee, jpeg, and raw image converted in adobe camera raw 4. While the first two seem to have round, grain-like noise, the third one has noise in the form of rectangles. (I oversharpened to make the noise clearer) I've always used photoshop for raw conversion and all sorts of editing, (I have cs3 by the way) so I'd very much prefer continue using it. But the noise it produces is simply synthetic and very ugly. I'm guessing camera raw 5 has the problem solved (if anyone else has ever experienced something similar anyways), but as far as I know v5 is for cs4 only. So what do you think, is it just something I do wrong, or should I give up adobe camera raw? If so, what should I use as an alternative?<br>

Thanks for reading,<br>

İrem</p><div></div>

[iremaltan]

<p>It's raw therapee v3.0 alpha 1 by the way.</p>

[wogears]

<p>Did you sharpen all three equally?</p>

[n-j]

<p>are these crops screenshots from the app or crops from rendered files ?</p>

[janne_moren]

It depends on the demosaic'ing algorithm. A converter like UFRaw lets you choose which converter to use, and there some method can give you maze-like patterns like this in some situations. All methods are compromises between conflicting goals of accurate color rendition with no bleeding, low noise, high detail and lack of artefacts like this. The best solution is of course to have an alternate method or two available and let the user switch in those cases the default method is unsatisfactory.

[wogears]

<p>I sharpened the first two examples--looks pretty much the same to me...</p><div></div>