the case that i am looking at might be a bit of a corner case - i was experimenting with Wei-Hao Wang's public dataset of the eta carina nebula, but since i was just playing around i was using DSLR RAW files and letting libRAW debayer them, with highlight clipping turned on. as a result there are saturated pixel values in the stars, and many places where there are only 1 or 2 channels where the pixel data is 1.0. this might be a debayering artifact since you'd expect stars to be fully saturated at the core and then drop off radially but this data does not look like that.
in this case, in the mosaic result from PMM3.0, i am seeing some of these pixels getting set to very low values in the green channel only. the R and B channels seem fine.
a couple of screenshots follow. on the left is the mosaic result (green channel shown) and on the right is the corresponding pane out of MosaicByCoordinates. the 2nd screenshot shows which pixels are saturated and in which channels (given the color of the pixel.) there's clearly a correlation between the partially-saturated pixels and the green channel pixels but it is not a perfect map. the green pixels are fine in the output from MBC, so this is not a registration artifact (but it occurs to me the partially-saturated values might be.)
the two files are actually available on google drive as part of WHW's public release: they are IMGP7198 and IMGP7199 in this folder:
if there is some setting that i'm missing in PMM please let me know. or maybe i should just not be using PMM on images like this?
thanks
rob
in this case, in the mosaic result from PMM3.0, i am seeing some of these pixels getting set to very low values in the green channel only. the R and B channels seem fine.
a couple of screenshots follow. on the left is the mosaic result (green channel shown) and on the right is the corresponding pane out of MosaicByCoordinates. the 2nd screenshot shows which pixels are saturated and in which channels (given the color of the pixel.) there's clearly a correlation between the partially-saturated pixels and the green channel pixels but it is not a perfect map. the green pixels are fine in the output from MBC, so this is not a registration artifact (but it occurs to me the partially-saturated values might be.)
the two files are actually available on google drive as part of WHW's public release: they are IMGP7198 and IMGP7199 in this folder:
20190202 - Google Drive
drive.google.com
if there is some setting that i'm missing in PMM please let me know. or maybe i should just not be using PMM on images like this?
thanks
rob