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Workflow for multiple night frames  


Hydrogen Atom Customer
Joined: 2 years ago
Posts: 1
April 3, 2019 04:38  


I've just started using APP and was wondering what would be the workflow to stack frames (light, darks and flats) gathered in multiple night of the same object and same equipment but different gain values.

Previously I was using DeepSkyStacker which allowed me to make groups (per night sessions) and stack all together into a single TIF file.

Any thought would be highly appreciated. Thanks.


This topic was modified 7 months ago by javrolijk

Red Giant Customer
Joined: 1 year ago
Posts: 71
April 3, 2019 14:17  

Hi Jairo,

APP has the option to process data from multiple sessions. Have a look at the 1) LOAD tab. At the top you can select "Multi-Session processing". Then when you load the lights, APP will ask you for which session they are.


HTH, Wouter

Main Sequence Star Customer
Joined: 2 years ago
Posts: 32
April 3, 2019 16:41  

Hello Jairo,

As Wouter says.

There is also another way. You can also calibrate each session separately and save the calibrated subs. Do that every time you have gathered exposure time for a subject (using the appropriate darks, flats and flatdarks and BPM). In due time you will have a collection of calibrated subs and when you want to integrate, you simply load all the calibrated subs as lights, tweak the integration parameters to your liking and off you go.

This is the way I do it, because there can a lot of time between sessions due to bad weather and calibrating per session, just after the time of capture, makes it easier for me to remember which flat belongs to what session as it is still fresh in my memory at that time. I also perfom an integration whenever I have added a new session, just to see if and how much it is going in the right direction and to evaluate if I am at the point of enough-is-enough. 

In the end, I delete the original subs and keep the calibrated ones. If you then want to add exposure time much later, say next season, it is a simple matter of making calibrated subs of the new exposures and throw them with the calibrated subs you already had in APP to integrate.




Red Giant Customer
Joined: 2 years ago
Posts: 71
April 4, 2019 11:49  

I agree with Anne - I used to wait to calibrate all my data when I had accumulated all the data I wanted to use in my integration, and it took a long time and was tedious finding all the proper flat frames to use for multiple sessions.

Now I calibrate the day after acquiring the data and save the calibrated frames.  This greatly speeds up the integration process when the time comes!