M42 Atik314L 0.8 FR ZS66

[Fay]

Mark, my mask is white checks with a whiter bit in the middle & a light grey surrounding it. The white bit, when superimposed, seems to be inverted, a grey colour not over exposed white.

[MarkS]

Fay,

I've put an example at http://homepage.ntlworld.com/the_shelleys/Astronomy/neb4.psd

Mark

[Fay]

Mark, I will have another go at this tonight.
Now what I get is, a white check mask with a whiter bit in the middle, the burnt out centre of the bright image, but the rest of the mask is still white not black, so when I process, it alters the whole of the main image, not just the centre.

[MarkS]

Check out my example - that will tell you what it should look like.

[Fay]

Thanks Mark. I got the dark one onto the main image, but when I do curves or any other processing, the whole image changes not just the centre. 

[Fay]

I think I have hit on my problem....................have not been aligning the long exposure with the short!!!!!!!!!!!!!!!!!!!!! Hence, that is why I get a muddy grey in the trapezium area, because it is a different part of the image showing through!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Can anyone tell me the easiest way to align the main image with the masked one.........PLEASE!!!!!!!!!!!!!!!!!!!!!!! Before I go madder than I already am

[Rocket Pooch]

highlight a layer, set the transparency to 50% do CTRL+T then move it about with the arrows, when your comfortable with alignment press enter.

or align them in maxim, aa or whatever your using.

[Mac]

another easier way is to rearange the layers so the layer you want to move is on the top, You can always change it back after.
then change the dropdown from normal to difference,
and then move the layer, if everything is in alignment the image will be Jet black.
Even one pixel out it will show the difference between the two layers.


Here are two layers one ontop of the other, only the top one is out by 1 pixel.


By changing the top layer to difference instead of normal, it shows you the difference between the two images,



If you them move the images around the differences are always higlighted, untill they are aligned completly.
Then the image is black.



all you do is then change it back to normal, and drag the layer to where you want it.

Dont forget, the two images will never align perfectly!!
as they were taken at different times, ect,
but if you look at two stars, you can align them over each other, ect.

[Fay]

Thanks Chris & Mac.
My two images look like they need a small rotation.............eek!

Mac that is very informative, I will have a go anyway