Share:
Notifications
Clear all

MAY 4 2026: APP 2.0.0-beta44 has been released !

New improved internal memory controls should now work on all computers

May 1 2026: APP 2.0.0-beta43 has been released !

Improved internal memory controls (much more stable and faster on big datasets), fixed CPU image viewer, fixed Narrowband extraction demosaic algortihms.

Apr 29 2026 APP 2.0.0-beta42 has been released !

New improved Normalization engine, Fixed random crashes in integration, fixed RGB Combine & Calibrate Star Colors, fixed Narrowband extraction algorithms, new development platform with performance gains, bug fixes in the tools, etc...

Apr 14 2026: Google Pay, Apple Pay & WeChat Pay added as payment options

Update on the 2.0.0 release & the full manual

We are getting close to the 2.0.0 stable release and the full manual. The manual will soon become available on the website and also in PDF format. Both versions will be identical and once released, will start to follow the APP release cycle and thus will stay up-to-date to the latest APP version.

Once 2.0.0 is released, the price for APP will increase. Owner's license holders will not need to pay an upgrade fee to use 2.0.0, neither do Renter's license holders.

 

M31

4 Posts
2 Users
6 Reactions
3,329 Views
(@vjagannathan)
White Dwarf
Joined: 6 years ago
Posts: 5
Topic starter  

Here are two pics of M31 processed with APP. They were taken with WO's 51mm f/4.9 Petzval space cat refractor mounted on an Ioptron sky guider and using a modified Canon T7i further containing an Astronomik filter to counter light pollution issues when shooting from a city. 

One of them is at 31 x 90sec at ISO 1600. Only light frames. No darks and no flats.

The other one is at 28 x 180sec at ISO 1600 i.e. doubling the exposure. Again, only light frames.

I see a bit of an improvement in the latter. 

I think that the TOOLS tab #9 in APP is a real gem although it does take a lot of experimentation to get it do what I want it to do. If I can get a grip on it I think my images will also improve.
 
I have a concern in that I did not apply cold pixel and hot pixel type of corrections to avoid "losing" some stars but is so doing my images are a little dirty. I also did not take any dark frames to further reduce noise. I also did not shoot different parts of M31 at different exposure parameters and combine them into an overall mosaic. Now, I am wondering how much these would have affected the final image. My question is how far can one continue this experiment to get better results?
 
Any critiques, constructive advice/suggestions would be appreciated.
 
Andromeda 02142020 v2 St avg 5054.0s SC 1 3.0 none x 1.0 LZ3 NS full qua add sc BWMV nor AAD RE noMBB lpc cbg cbg csc mod St
Andromeda 01292020 v4 St avg 2795.0s NR x 1.0 LZ3 NS full qua add sc BWMV nor AAD RE noMBB mod St
 


   
artem and Mabula-Admin reacted
ReplyQuote
(@Anonymous 174)
Joined: 9 years ago
Posts: 5702
 

Great first results and good that you're open to suggestions! Having proper bias and darks will definitely improve the result. A nice long dark and (when you have cold pixels at least) a good flat will make it possible to create a BPM (Bad Pixel Map) which you can use for quite a long time to correct for all the hot pixels and such. Don't worry about the stars, this shouldn't be a real issue. Dithering will further help you in reducing noise (for instance it might lower the vertical stripes in your background).

Flats, always a difficult topic and tricky to make proper ones, definitely is a good thing to learn. It will enhance the overall quality as well by a lot. You have some dust on your frames (the darker spots) and these can then be removed and the overall background can be corrected much nicer. When you have all this in place, you can go and experiment with longer exposures or at the very least, more frames. I would keep the best frames of these attempts and add more later, aim for 100 or so in total and see the improvement.



   
Mabula-Admin reacted
ReplyQuote
(@vjagannathan)
White Dwarf
Joined: 6 years ago
Posts: 5
Topic starter  

Thank you @vincent-mod. I really appreciate your careful response. Thank you for clearing up my fears about "losing" some stars by applying corrections without understanding how they work. I especially like the idea of saving good frames and to bank them for future processing. This means that no session is ever completely wasted. For the flats, I thought that because of the Petzval design that I didn't need to fight that battle this early. Again, my appreciation to you for taking the time to help me improve.



   
Mabula-Admin reacted
ReplyQuote
(@Anonymous 174)
Joined: 9 years ago
Posts: 5702
 

No problem at all Vasu, always nice to help if someone wants to learn more! If you have any further questions or run into trouble, don't hesitate to ask more.



   
ReplyQuote
Share: