1
Software Dev / How the darkframe substraction procedure is implemented?
« on: June 09, 2022, 03:27:35 AM »
Hello,
for the scientific application, I need to know the exact way, and how the data from the sensor are processed. We made some attempts to analyze that directly from the camera output. Our results are:
Especially the first point is quite strange because the 'RAW' data are supposed to be RAW, therefore we expect unprocessed values directly from the image sensor. Is there some option to disable dark frame subtraction at the least for raw12 data output? Where is the darkframe or black calibration applied? Is there some other processing made on "RAW" data? Is there a possibility to backup the required data and process the image outside from camera?
I'm attaching the screenshot where the subtraction of intentionally incorrect dark-frame is visible in all output formats (RAW12bit, TIFF, TIFF-RAW)
for the scientific application, I need to know the exact way, and how the data from the sensor are processed. We made some attempts to analyze that directly from the camera output. Our results are:
- Camera substracts darkframe even in case of "RAW" data output
- There is no exact control of what darkframe file is actually or has been used for the substraction
Especially the first point is quite strange because the 'RAW' data are supposed to be RAW, therefore we expect unprocessed values directly from the image sensor. Is there some option to disable dark frame subtraction at the least for raw12 data output? Where is the darkframe or black calibration applied? Is there some other processing made on "RAW" data? Is there a possibility to backup the required data and process the image outside from camera?
I'm attaching the screenshot where the subtraction of intentionally incorrect dark-frame is visible in all output formats (RAW12bit, TIFF, TIFF-RAW)