AAVSO report shows unusual comparison star magnitudes
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You just updated astap again?
No but you could get a message (update available) from Sourceforge a few hours later. I have no control on that. It is an automatic routine which can react in 15 minutes or hours.
Resume, you do not need to update. There is only one version 2025.07.16.
Hi Han,
I ran the latest version 2025.07.25 with no problems (see below), but both the variable list and the graph remained empty while comparison stars are found. I tried different online and local DBs with the same result. I have added an image. Could you take a look?
cs Axel
PS: I am on vacation and travelling so I may not be able to answer every evening.
23:00:10 Using star database V50
23:00:10 Photometry calibration for POINT SOURCES successful. 272 Gaia stars used for flux calibration. Flux aperture diameter: 12.09 pixels. Standard error MZERO [magn]: 0.004%. Annulus inner diameter: 23 pixels. Stars with pixel values close to 4092 are ignored.
23:00:10 Photometric calibration is only valid if the filter passband (Green) is compatible with the passband reference database (V). This is indicated by the coloured square icons in tab photometry.
23:00:10 Limiting magnitude is 13.54 ( σ=0.004, SNR=7, aperture ⌀3.0) Saturation at ≈ 8.1
23:00:10 Using local variable database. Online version can be set in tab Photometry
23:00:10 Added 16 annotations.
23:00:10 Added columns for 000-BBF-727 V=4.047(0.008)_B=4.642(0.012)
23:00:10 Added columns for 000-BBF-709 V=6.41(0.1)_B=6.53(0.1)
23:00:10 Added columns for 000-BJR-561 V=8.546(0.034)_B=9.155(0.052)
23:00:10 Added columns for 000-BLS-593 V=8.599(0.034)_B=8.961(0.052)
23:00:10 Added columns for 000-BLS-594 V=9.207(0.036)_B=9.549(0.056)
23:00:10 Added columns for 000-BBF-697 V=9.476(0.076)_B=9.595(0.088)
23:00:10 Added columns for 000-BJR-564 V=9.48(0.038)_B=10.049(0.061)
23:00:10 Added columns for 000-BJR-565 V=9.578(0.04)_B=10.138(0.065)
23:00:10 Added columns for 000-BKB-894 V=9.612(0.041)_B=10.777(0.08)
23:00:10 Added columns for 000-BLS-595 V=9.995(0.049)_B=10.623(0.085)
23:00:10 Added columns for 000-BBF-700 V=10.286(0.079)_B=10.566(0.103)
23:00:10 Added columns for 000-BLS-596 V=10.41(0.053)_B=10.97(0.082)
23:00:10 Added columns for 000-BKB-896 V=10.454(0.057)_B=11.084(0.102)
23:00:10 Added columns for 000-BLS-597 V=10.676(0.057)_B=11.393(0.081)
23:00:10 Detected a total 14 stars
23:00:11 Using local variable database. Online version can be set in tab Photometry
23:00:11 Added 16 annotations.
That was a puzzling problem. It was caused by being in constellation Per. The code is reading from AAVSO the period by detection Per but was detecting the Per behind constellation. I have changed detecting now to Peri.
I will upload the correction as ASTAP development version 2025.07.27. I will upload the stable version in a week or so since Sourceforge will automatically send an email out to all people which are subscribed to Sourceforge for updates.
Enjoy your holiday.
Han
Hi Han,
I installed development version 2025.07.27:
running with local DBmag11 I get all the variables in the field and their respective magnitudes.
running with local DBmag13 I only get two variables as before (attachment)
running with online DBmag11 and DBmag13 I get all the variables but many of the variables have some unrealistic magnitudes (attachment).
But perhaps I did not download the correct development version? As far as I am aware both production and development version are marked identically in the Help: About ASTAP menu entry. Perhaps you could send me a link to the file to make sure I installed the right version.
cs Axel
Hi Axel,
The link to the development version Windows is:
https://www.hnsky.org/astap_setup.exe
It should tell you the version 2025.07.27 in the Help, About.
The local database only displays variables which have an AUID designation. Are you suggesting some variables are missing? The current local variable database version excluded any variable not having an AUID number. Those wher excludes becuase to report you first have to request an AUID. I used the database from 2 to 3 years ago to avoid redoing everything.
Which magnitude is wrong in your screenshot astap2.jpg?
I will check tommorow myself again.
Han
There are some stars missing in the local database. I will redo the download/ retrieval from AAVSO. This will take maybe 48 hours. Then I have to process the files to remove double entries and convert them in a good format. This will take some time.
The conversion took some significant manual handling. I will also have a look if I can correct the old database. The only problem seems the AUID seems somehow missing. I deciding a month ago to exclude stars without a AUID because there where too many Gaia stars including with a very minor variation. An other option would be to filter on delta magnitude and remove only the once the once which have a very low magnitude variation. That would be a quicker solution.
The magnitudes of the COMP star look okay in your image. Variable V0509_Per seems currently fainter then the normal range.
There are a couple of other variables in the field that have an AUID (see attachment) so they should be found with the local db.
Restricting the range to say 0.01 mag seems reasonable - at least I know no amateur observing millimag variables.
There are two 10 mag observations in the graph - just take a look at the lower part of the diagram
cs Axel
I decided to update. I have my online extracting program running again and will have up to date extracted data set in 12 hours or so. After that handling will take some time because there where already around 500.000 variables a few years ago. Due to the partly manually entered inputs there is some inconsistency in the values with brackets and so on.
Last edit: han.k 3 days ago
Here an example of an extract. It is full of Gaia stars with a tiny variation in magnitude. I have markled that in red. For a database correct but for displaying unfiltered in a map not so good.
Okay I have to restart extracting from AAVSO since some variables where missed by my program . This will produce a few million variables, mostly from Gaia DR3 catalog. This just takes time. Spreadsheet handling is also no longer possible due to the number of rows. I have created my own tools for handling this amount of data.
Looks like an awful lot of work, even with skripts to handle the data. What kind of minimum amplitude do you expect to use as cutoff?
Of course you could instead add a period filtering feature so users can decide if they want to see variables with very small variations. That could be easily added to the period list you recently introduced. That might save you a lot of work filtering the data.
I think I will stick to a filtering where either 1) AUID available or 2) Magnitude varation is larger then 0.1 magnitude. This will remove most Gaia DR3 entries with a very low magnitude variation which are polluting the map. Would that be a good idea?
Once I have the data downloaded, the preparing of the database will go reasonable easy since I have now preperared some brute force code to do the filtering. The previous spreadsheet solution is no longer practical due to the huge amount of data. Data is 2 to 3 times larger then a few years ago. So maybe 3 or 5 million rows.
Last edit: han.k 2 days ago
AUID available makes of course sense. But I think a minimum variation of 0.1 mag is too rigid. I am observing variables with 0.05 mag variation or less with a standard DSLR and telephoto lens. Larger telescopes with CCD have no difficulty going lower. 0.05 mag might be a suitable compromise.
Okay. Will be relative easy to adapt once I have the new raw data. The only worry is this will result in a lot of stars. The same as the online version does display.
That's why I thought an additional choice to display or not display low-amplitude variables might be useful.
VSX extracted. Now I will redo the VSP extraction.
I think processing with condition AUID available or magnitude variation >0.1, I already have around one million variable stars. From those maybe 1/20 has an AUID but I have to check later. Today I have garden work to do.
Happy gardening! ;-) I don't want to think about how my garden looks when I come back after two weeks of vacation...