I'm not sure what your merging process is, but the individual colour channels aren't overexposed so you might need to take some more care in combining and post-processing.
Here's my effort at combining your individual R,G,B bitmaps in AstraImage, taking it to photoshop and aligning the channels, adjusting with some curves, colour balance and saturation.
Your original is on the right. I thikn the elongated shadow is simply due to the conditions and the fact that you were using an undriven dob.
|