App solves it but command line doesn't
Stacking program, astrometric (plate) solver, fits file viewer
Brought to you by:
han59
Menu
▾
▴
Hello,
I found that ASTAP can solve my images easily if loaded in the application, but can't solve them through command line.
This is an issue since, as many, I'm using ASTAP to solve through other software (in this specific case N.I.N.A).
After some investigation I tend to think the reason is due to the fact that through command line ASTAP can detect only 7 stars (my image is bad because it comes from short exposure, using a bad guide scope into a small sensor in a very light polluted area) while through the app it can detect 41 stars thanks to the colour levels adjustment and colour-smoothing filter.
Can this actually be the reason why the app solves it and the cli doesn't ?
Any chance to be able to run the colour adjustment/filter through the cli ?
Any other option ?
Thanks for the support and great work,
Ruggero
There should be no difference between solving using the command line and in the application. It must be the difference in settings. The command line can overrule the settings.
Can you retrieve the .ini file created by ASTAP if you solve an image in Nina. In the .ini file the command line is stored. I' can't rememeber where nina stores the .ini file but I assume you can find it in Nina logging.
The test1.fits image is only 2 seconds exposed. A longer exposure time will help. ASTAP could not solve the image initially. Unfortunally the raw colour image is 1936x1096 pixels so binning 2x2 will make the dimensions too small. The problem with raw colour images is that the red, green and blue sensitive pixels are not equal. There is a difference in bias/pedestal value. ASTAP can only solve test1.fits if you normalise it using button "Test flat normalise" in tab stack method. then red,green and blue pixels get the same background value improving star detection.
To improve solving you could experiment with option "calibrate prior to solving" (apply dark, flat) in tab alignment.
Han
Thanks Han for getting back at me.
A bit of background: my goal is to use NINA three point polar alignment, as I'm not polar aligned, long exposure results in star trails which are bad for platesolving, so I'm stuck with short exposure.
I don't care what NINA does with the command line, I will work on that later. My goal is to find a way, if possible, to make ASTAP solve my image through a command line invocation which I can fully control.
What is ASTAP doing by default with the app that allows to solve the image but doesn't do it through command line ?
I'm attaching:
- test1.ini and test1.log, output of a command line invocation with no option (except for the -log).
- asta_log.txt which is a cut and paste of the expanded log from ASTAP application, which solves successfully.
The .ini is normal.
The difference with the command line is that in the application you convert it to colour. This is an other method to equalise the pixels.
If you look to the raw, typically the 2x2 pixel contain sthe following pixel background values,
18000
13000
7000
14000
So very unequal. This is typical for a colour sensor. But it is highly confusing for the solver to detect stars. Normally you just bin 2x2 and the problem is solved. But your camera has not much pixels. So you have to solve in 1x1.
In the application you can do three things to fix this problem:
1) Convert to colour. ( I assume you have auto demosaic on in viewer menu tools)
2) Use the button "test normalise flat"
3) Apply a flat (and darks).
So this is a little exceptional situation. If you switch in the viewer, menu TOOLS the menu option "auto demosaic" off you will see the raw file in grey. Have a look to the pixel values
Option 3) is the only solution possible for using the command line.
Do the following:
If this works, it will also work in the command-line. To improve you could also make darks and flat-darks and add them.
Alternative, maybe it is possible change the gains for each colour in either the application or driver to make them more equal.
Han
Last edit: han.k 2022-03-11
Reviewing the problem, I will study adding an option to normalise the image prior to solving. That will be easier. Maybe this afternoon.
Han
Try this version 2022-3-11
http://www.hnsky.org/astap_setup.exe
and activate option normalise (and save settings or hit solve button tosave). See screenshot.
Wow that was fast! Thank you!
I can't test it until late this afternoon (CET).
If I understood correctly, I have to disable the "auto demosaic" and try to solve through app (this should fail as it is similar to the pure command line usage).
Then I will can try with your new option on and see if it solves.
I will let you know.
Thanks again. (and hoping that if it works, you could add the normalize option to the command line interface)
Last edit: Ruggero Susella 2022-03-11
Yes correct.
I will rename it to "checker pattern filter" That is more understandable. This will also effect in the saving of the option. So download a new version in a few hours and check the setting of this option.
Han
Updated now. Same link.
Downloaded from your link and installed.
Removed the auto-demosaic and tried a solve: unsucessfull, as expected.
But I can't find the new option in the alignment tab, attaching screenshots.
Sorry, my mistake. Problably re-installed a previous version.
Now I can see the option and I'm testing it, will update this post.
UPDATE
I had 5 images to test with (of course it's cloudy).
1 image had star trails due to mount not tracking and wasn't able to solve it (I've also tested the demosaic and still no solution)
The other 4 images weren't solvable with default options but ASTAP solved them when the "check pattern filter" option was enabled!
I've also tested it through the command line with the -"check y" and got the same expected results.
Thank you very much for your support!
Ruggero
Last edit: Ruggero Susella 2022-03-11