Stitching together images in Framing & Mosaic

I would like to shoot a 40-frame Mosaic of the Andromeda galaxy. That would be 40 Lum X 10 stacks (400 Lum), plus RGB. So that’s 40 x 10 x 4 images!

Ideally I would want to get the “40” out of the equation and only see 10 L, 10 R, 10 G and 10 B. In other words, the 40 frames would be “stitched” together into one giant FIT.

Is this possible? If so, is there a tutorial I can reference?

Mosaic processing is the responsibility of your image processing software. I believe your math is 40 frames, each composed of 40 subs would be 1600 subs times the exposure length of each sub. Something north of 8000 minutes of imaging.

PixInsight has an excellent Mosaic assembly procedure, as I am sure other packages do as well. However, this size “fit” file (about 40 gigabytes if using a KAF-8300 and my math is accurate) would require a lot of memory and CPU horse power to process and then be resampled down to 1200 x 900 or similar so people could view it.

Google “PixInsight Mosaic” for details of how this is done.


A great starting point for PI Mosaics is here:


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Thanks guy. Checking Pixinsight now. Looks like I’ll be using 30 frames (5W
x 6H) at 2758 x 2208/frame for 1x1.

Here is a well done video tutorial on using PI to do a 12 frame mosaic:

This video is based on H-Alpha subs, which makes the mosaic a little easier to assemble than when you are using RGB subs – where the color balance across all the “master” subs becomes a challenge. I would suggest you start out with some 2 x 2 mosaics in monochrome and then move to a 2 x 2 mosaic in color before you start shooting the subs for the bigger mosaic.


There is also this shady character @harry that makes an excellent video for mosaics in PI:

Lots more where that came from too…