gradientHDRComposition

[andy274]

Hi guys,
this may not be easy to explain.  I have images of M42 at differing exposures.  15mins (m42_900final) & 2mins (m42_120rotate).  The 15min exposures were captured in a different orientation to the 2mins as they were taken over different nights.  I have resolved that using rotate & aligned using dynamic alignment.  The trouble is, the result from dynamic alignment has left m42_120rotate with empty black areas which now i can't resolve in gradientHDRcomposition as the error message - current image width differs from first image width.
Is there any way that i can fill the black areas of this image with data from the 1st image so i can properly use the HDRcomposition to combine both images?
Does this even make sense to anyone? Also, no laughing at the state of both images, I'm just beginning processing like this!
Cheers
Andy

[georg.viehoever]

The general idea makes sense. However, the error message points at different image sizes - Dynamic alignment should have left you with two images of exactly the same size. Have a look at the lower right status bar of PI, it shows you width and height of the loaded image. They should be identlical for both.

Georg

[andy274]

Hi Georg
I think I've worked out what went wrong initially - a schoolboy error! I don't think i rotated one of the images without saving it prior to running the gradientHDRcompression meaning that it was (I'm guessing) trying to compute the images in different aspect ratios... it was only after i checked both images as you recommended & they were both the same size that i looked at something more elementary!
Cheers
Andy