If your relative proportions are accurate, that means Photosphere is doing a good job of solving for the system response. However, there's no way for it to solve for the absolute calibration. It just uses a value that is approximate based on ISO, which it sounds like you don't know. Select a region you've measured and use the "Apply" button to calibrate against your measured luminance. Use the dialog option to save this factor for your camera and you should be good from then on. (You'll need to be consistent about the camera make, model, and version in your added Exif header, though.)
-Greg > From: Kevin Van Den Wymelenberg <[email protected]> > Date: June 17, 2011 2:55:00 PM PDT > > Greg, > > Thanks for the reply. My errors are in absolute terms. I have a Minolta > luminance meter and a Macbeth grey card in the middle of the scene. I am > also doing comparisons of absolute luminance values produced by the FireFly > as compared to the luminance results from my Canon camera on images captured > at the same time of the same scene. I have high confidence in my Canon > results from previous validations. The HDR that Photosphere resolves for the > Firefly at first look reasonable within the scene – it has logical variation > in luminance values. It is the absolute errors that I am worried about. > > Thanks! _______________________________________________ HDRI mailing list [email protected] http://www.radiance-online.org/mailman/listinfo/hdri
