I don't know what software they used but the BBC Stargazing Live show did a
citizen science project stacking images of Orion taken with any old camera to produce a detailed shot.
Gav,
if I was in your shoes I would start with finding a shot covering the target you want to reveal at the resolution/detail you want in the final shot. Even if you find a photo online. This you don't use in your final shot, its just a target to align your shots against.
With PixInsight I'd use Dynamic Alignment. Load your target image and one of your images into PI. Open DA then click on to target image then click on your image. Now you click on a star in the target image and a marker should appear in your image probably nowhere near the same corresponding star so you'll have to zoom in and manually drag it to the matching star. Repeat for a second star. Now PI will understand the scale difference between the shots and adding further stars around the target shot should match up in yours better. When you apply the alignment, your image will be rescaled to match your target image and image size. You might end up with a black/empty image with your image a rescaled postage stamp somewhere in the shot. Save this, I make a subfolder called "reg" for registered images to keep them together and seperate from source sets.
Rinse and repeat with your set of source images. It'll be time consuming and tedious but at the end you will end up with a set of images all aligned and at the same scale regardless of the gear used to take them.
Now you can throw them all into the ImageIntegration module to stack them to a single image. After that I'd do a screentransferfunction stretch to see if the image edges look good or need cropping, then crop, dynamic background extraction, histogram stretch. This at least will get you a "final" image.
You do not need to do anything for colour calibration, you can even do all this with JPGs only if its all you have. The above process is a simple workflow, there are options in all the steps to improve data quality and a few other things you can do to try to get a more technically accurate final shot but the above will get you 99% of the way there; its reliable and repeatable and anyone with PI should be able to get a result. I tried using Photoshop years ago to align and stack but never got results i was happy with, I found ways of using panorama stitching software to get my source shots aligned perfectly so i could stack them properly in photoshop. Once I figured it out in PI though I haven't looked back.
No doubt there are ways of doing it with all other packages, I know this method works and while PI isn't perfect it suits my needs. Figuring out how to use your data is half the fun and its great to see features and faint objects be revealed with even poor quality starting shots. Good luck!
i actually wrote a longer reply but it seemed to disappear, so reposted with a shorter response.
! Better start saving those pennies again.
