The image is a composite of 4 exposures with 120 AgfaOptima 400 hypered. The exposure times where 1 hour, 20 minutes, 5 minutes and 2 minutes.
The instrument is a 400mm f/8 Hypergraph.
Image processing:
The 4 images have been scanned with a UMAX Powerlook 3000 and blended with PictureWindow. It is important to use "blend" and not "add" in PictureWindow.
In Step 2 I have created a B&W image of the stacked color image. I removed all the stars in the image and made a gaussian blur with a radius of 80 pixels. Then I shifted the Histogram so that the background in the mask was completely black and only the brighter parts of the nebula where present. I subracted the blured B&W image from the stacked color image to produce a unsharp mask. Then I streched the contrast to produce the final image that can be seen above.