Hi all
I havent actually taken a new image, what I tried was combining my Baader UHCS filtered shot with an older unfiltered shot, using Photoshop CS, manually stacking (and rotating) the 2 images to get all stars lined up. Here is the result
http://www.users.on.net/~josiah/baad...teredsmall.jpg (full frame image)
Compare with
http://www.users.on.net/~josiah/baad...teredsmall.jpg which is the Baader filtered shot, and
http://www.users.on.net/~josiah/temp/helix45min.jpg (Both cropped)
The unfiltered one gets mostly blue, whereas the filtered shot gets plenty of red, the combo a more even balance of both. The filtered component is 10 and 15 min ISO 1600 shots, the unfiltered part is 3 x 15 min ISO 400 shots.
This is the great thing about computers, one can go back to old images and combine them with more recent ones. Even ones taken with different telescopes could be combined you'd just have to resize them to the same image scale.
Scott