Pendleton, OR
ASG Observatory
NGC2244
IC405, IC410, IC417, NGC1931
NGC 3372
NGC 1499
NGC7000
M45
Horsehead & Flame Nebula
Barnard 33
Stacking images is the first process you take when finished with your imaging process. You can stack images from color or monochrome subs and produce detail rich images with many hours of image data. For those new to stacking images, it’s the process of taking all your small images and integrating them on top of each other, aligning with the stars in them, and calibrating them with your camera calibration files.
The process can be fun and using software such as Deep Sky Stacker (DSS) or Astro Pixel Processor (APP) can be fun to experiment with. I have done a review on my end after using both tools and really like the tools and options in APP, however, it does cost compared to the free DSS option.
DSS is free, and while I don’t mind paying for software, I felt APP was a little expensive for stacking software.
DSS is much faster, but far less flexible. App does have a few areas it could improve in user interface flow to speed things up, even a simple process with defaults option.
APP excels here and offers just more features. Whether you need them or not is up to you, but I feel the quality and combining of subs is better in final images over DSS.
APP offers multi band blending and Local Normalization features that make your mosaics blend almost perfect, as well as options to control this. DSS will do mosaics, but I felt it was better controlled in APP.
As a software developer, I think both could benefit from an easier to use User Interface. Both have quarky designs, APP with it’s tabbed steps and DSS with it’s odd menu structure. Not deal breakers, but room to improve.
APP excels in offering options to customize how you stack and normalize your images. This alone to me is worth the cost as you would use it with every image set you develop. DSS does offer a few options, but has a ways to go to get to the formulas utilized inside APP.
In my opinion, both are great tools, and DSS offers a good tool for being freeware and gets the job done. Using extra steps in photoshop you could get 99% of the way there with what APP does, but APP wins in my book by giving more customization and better quality and controls, especially in mosaic modes and RGB combinations.
Two instructional videos comparing the same stacks.
This video we discuss combining the 30 subs of NGC7000 North America nebula using Deep Sky Stacker. The software is freeware and is a great choice to start stacking and get used to how the process of registering, integrating, and calibrating your images. The menu is someone non-intuitive but you quickly learn how it works.
DSS is very fast, and it registers and aligns things quickly, especially if you had a lot of subs to work with. You do need to kick out narrow band individual calibration stacks separately which can be kind of annoying after a while, and the option sets to adjust things are just not at the level of the APP software, but if you want free, and you need a tool to get you 99% of the way there, it works great.
In this video we stack the same NGC7000 North America nebula 30 image narrowband stack to compare with DSS. APP offers many more options in it’s tool, and while it does cost several hundred dollars, it can produce a little better quality with the controls it offers. Whether that cost is acceptable to your not is entirely up to you.
APP does excel in several areas; its mosaic ability to multi-band blend and run local normalization on those mosaics is actually pretty incredible. It also offers some nice tools at the end to create RGB images out of narrowband channels, and even preview various color palettes before saving our your final stacked image. While all possible in post processing software, just handy to do it right there with previews in many cases as well as simple stretches.