Adding AIRMASS to FITS Header
Stacking program, astrometric (plate) solver, fits file viewer
Brought to you by:
han59
Menu
▾
▴
My FITS header (from ASIAir) does not include Airmass or CENTALT. I have added my coordinates in the asteroid and comet screen and can calculate Airmass and CENTALT in ASTAP. I can see the results in the Photometry tab. But I can't figure out how to get those calculated results into the FITS header other than to add them manually to each file. I know how to batch update the FITS header in ASTAP, but that adds a static value. I'm trying to have the program update the header with the Airmass result that it calculates for each file.
Is there a way to add these calculated values to the FITS header? I'm using ASTAP version 2024.03.11, 64 bit on a Macbook running Monteray 12.7.4.
Thanks for your help. Your program is great!
That is not foreseen. But it can be easily added. For example if the SQM values is added the airmass is calculated anyhow.
But what doe you want to do with the airmass & centalt value in the header?
Han
Wow, thanks for the quick response! I calibrate my FITS files in ASTAP and then upload them to the AAVSO's VPhot program. VPhot looks for either CENTALT or AIRMASS in the header to include it in its reports. Thanks for your help.
In the code I added this
ASTAP will add CENTALT to the files if you do a batch solve. See viewer menu TOOLS, BATCH MENU, BATCH SOLVE with option "Add Limiting magnitude and SQM "check marked.
The Mac version has to wait one or two days before I issue a version. The Window development version with this new change is here:
http://www.hnsky.org/astap_setup.exe
Han
Terrific! Thanks very much!
ASTAP version 2024.03.13 has been released for MacOS.
Since you work with the AAVSO's VPhot program, can you share some images and VPhot reports for comparing with ASTAP photometry. It is always good to double check.
Cheers, Han
Thanks Han, much appreciated. I'm pretty new to all of this, so I'm sure this must be operator error somewhere, but in either the Windows or Mac version, I'm unable to get the CENTALT line added to the FITS header. I've checked the "add limiting magnitude and SQM" box and run the batch solve with no luck. It adds limiting magnitude and a pedestal value, but returns an error for the SQM (which is nice, but I don't need it) and does not add the CENTALT line and value.
I've attached a sample file so you can see (I've edited the lat/log data out). Once I get up and going, I'm happy to share images and VPhot reports.
Sorry for the late answer.
Looking to the header you just have to specify once the pedestal in menu "SQM report based on an image" shortcut CTRL+Q. Since your not interested in SQM just enter 100 or 500. That's all.
I will see if I can make this independent from SQM
Han
The error message was in the header:
SQM = 'Error! Specify first fixed pedestal value in the SQM menu (ctrl+Q).'
Han
Certainly no need to apologize Han, I appreciate your generously sharing your time! Here is another file. I double checked that the Lat/Long coordinates are in the comets tab, the SQM line is checked in the batch file screen, and the Ctrl-Q pop up included 500 in the pedestal box (I also tried it with 100, 5, and with the dark/flat checked and unchecked). Unfortunately still no luck in getting CENTALT into the header. Here is an example with 500 in the pedestal box (and dark/flat unchecked). I'm using ASTAP version 2024.03.13, 64 bit.
Yes it does not work. Also the SQM is missing.
I will check tomorrow in the debugger why. Something is wrong.
Han
Today it worked here. I assume I made a mistake yesterday.
Maybe your position is wrong. For USA/Canada the longitude should be negative. Do you get a good altitude out of the SQM menu (CTRL+Q) See attached.
See also attached how to activate the batch menu and which option to switch on.
This should work if not we have to find the cause.
(Your image are already calibrated so I will skip the pedestal check in next version.)
Han
I just tested the Mac version. It does not work there......Need to debug again
Last edit: han.k 2024-03-21
I have recompiled. Now it works. I assume I used an older version of the source code for Linux and Mac. Sometimes I even had the impression it refuses random so maybe an undefined varaible. But it looks now dat it works reliable. Please test it and report back:
Version 2024-03-21:
https://sourceforge.net/projects/astap-program/files/macOS%20installer/astap_command-line_version_macOS_x86_64.zip/download
I finally got a chance to get back to the computer. I'm happy to report that I was able to get the CENTALT calculation added in both the MAC (preferred) and Windows versions. Thanks VERY much! Now my issue is that VPhot is still not calculating AIRMASS even though the FITS header now includes CENTALT, SITELAT, and SITELONG. I'm currently taking the AAVSO CCD Photometry class so I'll bring it up there to see if there's a work around. I'll let you know what I find out. But even so, I can work with this data, so thank you very much for your help!
If any change is required please ask. No problem.
Han
Eureka, I think I've found the solution. VPhot is looking for the term OBJCTALT instead of CENTALT. Once I added the line OBJCTALT to the FITS header and added the same data as was in the line for CENTALT, VPhot calculated the AIRMASS. So could I trouble you to change the CENTALT line to substitute instead the term OBJCTALT?
Thank very much.
No problem, I have added OBJCTALT to the output. The main Mac version is updated (2024-03-28) and also the Windows & Linux development versions.
Han