With the sweatspot, we can either push up the power so that we only use the central part of the image, and then stitch the power up frames into a big uniform mosaic.
Or we can use a stronger reducer so that the whole solar disc lies in the sweatspot, that would again form a uniform image.
Problem is, I cannot push too much on the reduction factor since it would require excessive in-travel. But again I guess this idea could be employed to generate good and uniform solar image in H-alpha. Time to think more.