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HDR Grayscale Imaging

Posted: Wed Dec 07, 2011 2:41 pm
by IDollar
Scans performed in 6.6 as 16 bit HDRi grayscale are not rendering in Silverfast 8 beta r3. The images load and preview fine but when processing status displays 'Cancelled'.

Re: HDR Grayscale Imaging

Posted: Wed Dec 07, 2011 2:56 pm
by LSI_Morales
Hi there,

Would it be possible for you to lend us one of those files to evaluate here? You might use dropbox to upload one or two files.

Thanks

Re: HDR Grayscale Imaging

Posted: Wed Dec 07, 2011 3:18 pm
by IDollar
I will gladly put together some samples tonight. Can you email me instructions on how to get the files to you? Or let me know where I can send you instructions and I will create an FTP account for you on our servers.

Re: HDR Grayscale Imaging

Posted: Thu Dec 08, 2011 3:18 pm
by IDollar
I have created several sample files for testing in a lower resolution than our normal workflow. They are in a zip file shared via dropbox at this url:
http://dl.dropbox.com/u/52611143/SFSamples.zip

I have included HDRi scans from Positive, Negative and Grayscale originals using Silverfast NikonSF 6.6.2r4a on a Nikon 9000ED along with sample outputs using each Silverfast HDR Studio 6.6.2r4a and Silverfast HDR Studio Beta 8.0.1r3. These are each accompanied by screen shots of the settings used. These samples highlight the issues mentioned so far in the forum re. gamma and HDRi positives, non-rendering of grayscale originals and exaggerated identification of artifacts using iSRD for Positive and Negative film scans.

I hope they prove helpful.
Ian.

Re: HDR Grayscale Imaging

Posted: Thu Dec 08, 2011 3:24 pm
by IDollar
Some further testing has revealed something interesting: if the output is set to 8 or 16 bit grayscale nothing will render but if the output is set to 24 bit or 48 bit (color) then HDRStudio 8.0.1r3 will render out an 8 bit or 16 bit grayscale file respectively. The issue here is one of color management.
The HDRi grayscale image gets assigned the working RGB colorspace when opened in HDRStudio 5. If the color management policy is active in preferences then the rendered result is a grayscale image tagged with the rgb destination profile. If color management is off then the result is an untagged grayscale file for which the user must assign the correct gamma (in my case, gray gamma 2.2 since the RGB working space is Adobe RGB).

Hope this helps,
Ian.

Re: HDR Grayscale Imaging

Posted: Fri Dec 09, 2011 2:44 pm
by IDollar
Quick update: tested the same on HDR Studio 8r3 running OSX 10.7.2 Lion and the HDRi Grayscale image does not render at all (previous test was r3 running under 10.6.8 Snow Leopard).
Ian.

Re: HDR Grayscale Imaging

Posted: Tue Dec 13, 2011 3:38 pm
by LSI_Morales
Hi Ian

Thanks for your pictures, we have used them for evaluation. The gamma issue most likely will be corrected in the next iteration of the software.

Cheers