FAQ - Frequently Asked Questions - Astro Pixel Processor Forum

How to stack colour HA-OIII with mono HA fits files

Stefan Rang — Fri, 27 Feb 2026 11:49:21 +0000

Hello,

I have light frames of my HA-OIII colour camera and a friend of me shared his HA and OIII mono fits files.

How can I stack the HA together? I need first to extract HA-OIII, but than it will be a master light file.

Or can select in tab 0 the colour HA and load the HA-OIII in session 1 and HA mono in session 2? And stack them together?

Analytical results: what do they mean?

Tom van Peer — Mon, 01 Dec 2025 16:03:20 +0000

Hi,

Is there a guide somewhere that help to explain all the entities in the 'Analytical results per light frame' windows and how the interpret the (absolute) values in the file list underneath. Hopefully it will be in the 2.0 manual but if someone can point me to a forum post somewhere that would be a great help! Thanks.

10664

Luminous stars problem: they are big

Luca Argalia — Sat, 30 Aug 2025 13:19:13 +0000

I have been using AstropixelProcessor for at least 4 years, and I feel very well, it is simple and gives me a good file to work on, unlike other soft and more powerful software.
I noticed, however, that in the final image if I have very bright stars (an alnitak example in horse head) the star appears to me very large,
Which before when I used another software did not happen!. The stellar reduction does not work, also because then the other stars are fine and are in line with my instrument, a Takahashi FSQ106; I tried to rework a shot of when I used a canon 40d with astropixelprocessor, it improved .. but the limose stars are larger! ..
In the attached photo those stars are even doubles, which with the old software distinguished them, now no longer and looks like a single and bigger star!.

Is there any parameter to set during the processing phase? I usually do not touch anything and it is as if it decides the software .. what is wrong?

10571 10572

Please help, APP has been working ok then all of a sudden errors, crashes seems mostly with Java maybe, thanks

Paul1966 — Mon, 25 Aug 2025 15:50:19 +0000

10560

Upgraded to macOS Apple Silicon - Need my license code please.

pallikas — Wed, 09 Apr 2025 00:42:27 +0000

can't find it in my emails or online account details.

?? about changing my account ID...

fred.klich — Mon, 17 Mar 2025 21:27:21 +0000

My wife purchased the original/initial license under her name as a birthday present for me a while back.

Can I use the Account Details panels to change the account name to my First name (Fred instead of Pam)? or do I need to start over?

Error

Peter Stüssi — Sun, 16 Mar 2025 10:25:46 +0000

Astro Pixel Processor - 2.0.0-beta34
Oracle GraalVM 23.0.2+7.1 - Windows-64-bit

Encountered error in module:
FloatPixelCalculator

Error message:
java.lang.NullPointerException: Cannot load from float array because "" is null

Cause:
Cannot load from float array because "" is null
xu.a(DataRejecter.java:1011)
xu.compare(DataRejecter.java:1009)
java.base/java.util.TimSort.binarySort(Unknown Source)
java.base/java.util.TimSort.sort(Unknown Source)

Java.lang error on integration

Stephen Wilkins — Sun, 19 Jan 2025 04:23:11 +0000

I'm processing simple (not a mosaic) narrowband data of the Tarantula Nebula, no problems or errors at earlier stages but on attempting to ingrate I get this message. Integration fails.

10126

Data taken with a ZWO ASI1600MM Pro, captured in Voyager. processed on a Windows 11 machine.

Appreciate any help.

Black Friday sale

Centaurus — Sun, 01 Dec 2024 10:03:34 +0000

My renter's license is still valid until February- if I grab the Black Friday opportunity to renew my renter's licence now will I lose the remaining 2 months of my current renter's license? Does the Black Friday offer mean the license starts from the date of payment or does it start when the current license has expired?

License code

Trevor Appleton — Sat, 19 Oct 2024 07:34:21 +0000

I used APP yesterday fine today its asking for my Licence code, where do I find it?