Pretty much both as it does both. But really I'm just experimanting. From last
night.... well early this morning the results showed a crisper over all Saturn
with a loss of resolution using the mask, kinda like the focus was better.
Where as without the mask the edges of the planet disc and ring system
were slightly more diffused. Which has had me thinking if I could used this to
improve planetary imaging, by mixing the crisp views of the mask with the
colour and resolution of no mask.

I'm basically just playing around here and seeing if I can improve on what I
have. And posting here hopefully hear from others and their experimentation.

regards,CS