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May 27 2026 APP 2.0.0-beta45 has been released !

Fully Multi-Threaded LNC, many improvements for the registration engine, platform upgrade, and further tuning of internal memory consumption and memory release back to OS.

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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.

 

Bottom of image is lighter than expected

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(@david)
White Dwarf
Joined: 8 years ago
Posts: 14
Topic starter  

For some reason I cannot fathom, I am getting odd results at the bottom of the frame during integration, but only on some channels. Specifically, the Ha channel.

If I take two calibrated FITS using the Ha filter, (both of which appear like this):

Before Integration

Then load them, analyze them, register them, normalize them, and finally integrate them, I receive this:

After Integration

Where the bottom becomes brighter/lighter.

Both the FITS were taken in the same session on the same instrument, one immediately after the other. 

I suspect it is a processing issue with me, but for the life of me I can't figure it out.

I would be most grateful for any suggestions.

Thank you!

david



   
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(@wvreeven)
Quasar
Joined: 8 years ago
Posts: 2134
 

Can you give us a little more info about the equipment you use and what images you have taken with them? What camera do you use? Darks, Bias, flats, dark flats? Or are you reusing masters that you have taken before?



   
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(@david)
White Dwarf
Joined: 8 years ago
Posts: 14
Topic starter  

I was able to correct the lightness by turning off the LNC. I don't know why I had overlooked that before.

Thank you,

david

 



   
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(@Anonymous 174)
Joined: 9 years ago
Posts: 5702
 

Mm, LNC shouldn't be a problem I think. It could be that if you look very closely to both images before combining them, giving them a big stretch to compare the backgrounds of both, you might see a difference where LNC is trying to correct it. Both images are corrected with proper bias and such right?



   
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