Camera response calibration
I try to calibrate the camera response using Hugin. I did 5 exposures of the same scene (with a tripod) with 1.66 EV difference in exposure time. They contain both underexposed and overexposed areas. I converted them to linear TIFFs with "dcraw -o 0 -M -4 -T". In Hugin, I automatically detected CPs and calibrated the relative "Positions" of the images. Then, I optimised the camera response. Here are my questions:
1. Why do the parameters depend heavily on the subject that I photograph? I did two exposure series with the same ISO and got those EMoR values:
-9.30828 1.73149 0.73602 -0.84421 0.39533
-5.33008 -0.68035 2.57487 -1.4287 0.49794
2. Does the camera response depend on the ISO number?
3. If I also fit the EVs, I get a difference between the fitted EV and the EXIF data of 0.4 for an overall EV coverage of the series of 7 EV. Is the shutter speed of my camera really so inaccurate, or is it not a good idea to include the EVs into the fit?
4. If I look at the preview in the "difference" mode, I see significant signal at the overexposed areas. Ideally, the difference preview should be all black. Is this normal?
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- English Edit question
- Status:
- Solved
- For:
- Hugin Edit question
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- Solved by:
- Torsten Bronger
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