I have stacked LRGB frames from WBPP. I open the masters and combine the RGB into a color image. Both the L and the new RGB frames have a strong gradient. I am able to run SpectrophotometricFluxCalibration on both but when I run MultiscaleGradientCorrection with the MARS DR2 database enabled on either one, I get the default gradient correction with a warning that “Reprojected data outside reference image region - reference frame ignored”. First question is why does this occur, since I thought the new MARS covers the entire northern celestial hemisphere and these frames fall entirely within the northern hemisphere.
It turns out that the correction to the RGB frame is acceptable and removes the gradient completely, however, the correction to the L frame doesn’t eliminate a dust donut that my flats failed to correct. I’d like to use the corrected RGB frame as a reference frame to remove the gradient and dust donut from the L frame but I keep getting errors. If I use the RGB frame as the reference, the error is “Incompatible reference image color space: RGB.” So I extract the L channel from the RGB (RGB-L), run the SFC process on it, image solve it, and use it as the reference frame but now I get the error “Error: The reference image does not include the target image: RGB_L.” Second question is how is this possible? They are the identical regions of space. Finally, if I crop the L frame by about 5% around the edges, I get the error “Error: The ratio between the target and reference image fields exceeds the acceptable range.” I get that even with a severe crop of 30-40%. Third question is why is this error popping up? The image fields are nearly the same size.
Anyone know what I’m doing wrong with the MSG process?
Ron
