Image blending question

Hi all,

I remember a while back reading a tutorial for blending short exposure images with long exposure images to help bring out details in burned out areas. My example is the classic M42. I have a series of 120 sec frames where the trap is burned out and a series of 2 sec images that show the trap and want to blend them. I know it has to do with layers, like in Photoshop, but I'm not sure of the steps. Does anyone know of such a tutorial?

Thanks!!
Paul

Hi Paul,

Copy/paste the image of the nebula over the image of the trap. This will automatically create a new layer. F7 will bring up the layers control window.

Use the eraser and erase what you don't want on the nebula image exposing what you do want in the image underneath. Experiment with the erase type/size and amount. I use brush and start at 25% opacity.

If you haven't already aligned them use the adjustments in the layers box to make the top layer transparent enough to see both images and then align them. I use Ctrl A and the T which is Select all and transform. Just make sure you have selected the layer you want to move first. Also enlarge the image with Ctrl + and then using the arrow keys will give you a fine adjust.

Try

http://www.astropix.com/HTML/J_DIGIT/COMP2.HTM

for a complete description of this commonly used technique. There are other ways to do the same thing.

Alex