Editing

Import tif, image->mode->16bit
Select target area, inverse, filter -> rc astro-> gradient -> middle + bottom
Magic wand, select everything; select ->load->subtract, filter -> rc astro-> gradient -> top + top
levels -> move black slider to just left of histogram start point, grey a bit left (120)
- repeat as neccessary, watch for noise
Curves: use finger button to select medium point in sky, everything above that will be brightened
- select another anchor point right above, 4 or so more, then adjust
Filter -> Noise and Sharpen

Astrophotography