Some quick responses: 1) You do need to use the -o option in your pcomb command, but it only applies to the immediately following input file. Therefore, you need to put the "-o" between your two file names, or change their order to keep the absolute values. Displaying the output with ximage, you can use the "-e auto" option to bring the values in the the correct range for display (i.e., tone-map the result).
2) There is no easy way for Photosphere to figure out whether a fish-eye lens is being used. I would have to create a lens database similar to Photoshop CS5's and read the hidden maker tags in the Exif file, and still it would only work "sometimes." You are better off adding or correcting the VIEW= string as Jan suggests using the "vinfo" command in Radiance. Cheers, -Greg > From: Rashida Mogri <[email protected]> > Date: September 28, 2010 9:37:38 AM PDT > > Hi Greg, > > I am in the midst of trying to get Evalglare to accurately process HDR > images. In order to account for light-fall from a Canon + fish-eye generated > HDR, I have tried to multiply by the original HDR image with a correction > factor using the pcomb command. However, the resulting image does not > maintain similar luminance values as the original (as it should particularly > for the center part of the image that is only multiplied by a factor of 1). > > I am using the following command line and would appreciate any guidance on > why the luminance values are so affected: > pcomb -e "ro=ri(1)*ri(2);go=gi(1)*gi(2);bo=bi(1)*bi(2);" vignette_283.pic > Chauhaus3cr.hdr > Chauhaus3Bvg.hdr > > My initial attempt actually used the -o function to normalize the values of > the image before processing, but the resulting vignetted image was very dark > and the luminance values had drastically dropped -- pcomb -e > "ro=ri(1)*ri(2);go=gi(1)*gi(2);bo=bi(1)*bi(2);" -o vignette_283.pic > Chauhaus3cr.hdr > Chauhaus3vg.hdr > > > As an aside to something Rob mentioned earlier, I do not believe that right > now Evalglare automatically only judges the circular view of the fish-eye HDR > while being processed. In order to get accurate results, the rectangular > images should be cropped (using pcompos) and also the view type should be > verified before processing. I have discovered that several of my Photopshere > generated HDRs are being judged as a perspective view rather than angular > fish-eye as I had assumed it would (vtv instead of vta) and that I had to > manually adjust this setting before getting accurate and meaningful Evalglare > results. (Greg -- is there anyway to specify the lens type in Photosphere > before compiling the HDR so that it follows through from the beginning?) > > Best, > Rashida _______________________________________________ HDRI mailing list [email protected] http://www.radiance-online.org/mailman/listinfo/hdri
