Severe posterization in shadows even in...

I've been evaluation Lightroom for a couple of days and I keep getting some very noticable posterization artefacts in the shadows of my images. I have applied no develop settings at all (not during import, none set under the develop tab). And, I'm not talking about the library, I'm talking about the ''develop'' view.



Opening the pictures in various other viewers (Macromedia Fireworks for example) dosn't reveal any noticable posterization. I've also made comparisons with my display calibration software disabled (SpyderII), just to make sure it does not mess something up, but still posterization in Lightroom and no posterization in the other utils.



My eval pics are taken with a high end DSLR (Nikon D200) set to high resolution, highest quality jpeg, no noise reduction, sRGB color space.



I would have imagined the ''develop'' rendering accuracy of a tool such as Lightroom to be of highest priority so I hope there's an easy fix to my problem. I like the tool and it pretty much covers my needs, due to the posterization artefacts I'm seeing is pretty much useless for ''developing'' digital images.



H
Severe posterization in shadows even in...
Are you seeing this artefact in a print, just monitor, or both?
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Severe posterization in shadows even in...
I havn't really done any *serious* prints from Lightroom, but the ones I just printed on my budget home printer seem OK to me.



As a pretty serious amature, it is important for me to be able to accurately determine the quality of the ''raw material'', if it's a at all a keeper, if any further processing is required and what artefacts the processing might introduce in the final image. Right now I can't tell if the image I am working on has decent shadow detail.



As I said, the posterization is only apparent in the shadow detail, so I'm guessing there's some sort of accuracy/truncation problem somewhere in the system, possibly related to gamma?



H

Yes, if by system you mean the whole enchilada.....
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Would you mind posting a screenshot? I've also seen this numerous times... and I'm curious if it's similar.



Thanks,

Rishi

OK, I put a couple framegrabs of jpeg:s as they aoppear on my system (and yes, I mean ''system'' as in ''file to my screen'' system) -one from Adobe Lightroom and one from Macromedia Fireworks, both with 1:1 scale for ''pixel peeping''.



I grabbed them of my screen (32 bit colordepth) and stored them as .png:s with Fireworks. I also put in a full screen framegrab and the original jpeg for comparison.



While I cannot guarantee that they are ''pixel perfect'' grabs (due to Fireworks and/or to me unknown ''smugmugerization'' artefacts), I beleave they render accurate enough to clearly show my concern. I think the posterization (and the *drumroll* -as usual- badly composed example images) is very obvious if you compare the decking of the Lightroom screenshot with the original jpeg.



http://kirneh.smugmug.com/gallery/2715837#143970500



H

Yup...I've seen this before too. I don't know what causes it.