Skip to main content


7 posts / 0 new
Last post
astrosberge's picture


Is it possible to have a tutorial to convert the measurement spreadsheet obtained with AstroImageJ to the AAVSO file format ?  

It should be interesting in having a plugins or a tool in AstroImageJ in order to format the data analysis measurement into the AAVSO file format.  

If someone of you has something / tuto / plugins to help, please it would be appreciate to have it.


Serge  (astrosberge at

gabriele's picture
AstroImageJ and AAVSO format

I agree, AstroImageJ seems really nice, too bad I haven't been able to find tutorials, plugins or ways to export in the AAVSO data format, so I'm really interested in this.

clkotnik's picture
AstroImageJ for General Photometry

I'm afraid I do not have the tools you ask about, but I can offer some observations as a result of my using AIJ a bit and thinking about this.

First, you need to recognize that AIJ does not offer much support for filters.  This seemed most problematic to me in the area of calibration where you will need to keep all separate folder structures  for straight yourself and calibrate one filter at a time.  There is no filter ID in the output.  While you can add columns to the output from the FITS headers, these can only be numeric values.  Thus you would need to parse the filter ID, say out of the file name.  Or perhaps create numeric values in the FITS header for your filters.

The other thing to consider is that AIJ deals in flux mostly.  You can put in mags for the comp stars and get a magnitude for the target.  You would need to do something to generate the required instrumental magnitude for the check star since the instrumental magnitudes are not reported by AIJ.  The two things you might consider as sources are the Source-Sky or relative flux.  You would have to dig into the AIJ doc to find out how it generates the target magnitude for single and ensemble photometry.  Or perhaps you calculate the target magnitude yourself.

You may find it hard to keep the various target, check and comp stars straight as I don't believe you can give them your own names.

And then there is color transformation...

All of this is not to detract from AIJ which does a very good job at the exoplanet photometry it is designed for.  I looked down the road of general photometry with AIJ and have decided not to pursue it myself.

Good luck,

Cliff Kotnik


astrosberge's picture
AIJ format

Thanks Cliff and Gabrielle

Sorry for my late answer. 

AIJ is powerfull and can do differential photometry easily.  The only issue is the file format.  It would be interesting in having an AVSO file format plugin in order to use it for AAVSO.  

As per some consultations, there is an appetite to create eventually a plugin but we just need a volunteer who is able to make it... and I am not a programmer. 


clkotnik's picture
Any Interest In Collaboration?

If you have some knowledge of python and would be interested in collaborating on a postprocessing program for the AIJ measurements file please let me know.  I have a prototype that I developed to handle the conversion to AAVSO, color transforms, etc.  It certainly is nothing more than a prototype, but perhaps could be refined.

best regards,


astrosberge's picture

I am interested in but I don't know Python.

It should be interesting for you to have a discussion with Karen Collins, the professor who is behind AIJ. Also,  AIJ is very exoplanet oriented and you should also have a discussion with Dennis Conti who is the AAVSO exoplanet man. 

Let me know more about your prototype but as I have mentioned, Pyhton is completely new for me.


clkotnik's picture
Perhaps We Should Define Goals


When I was first introduced to AIJ, it was from Dennis explicitly for exoplanet work.  That is why Karen developed it as I understand it.  As such, the main outputs are relative flux and generally the output from AIJ or a column subset of it are what the researchers require.  

So when I read your original post, I assumed since you were looking for the AAVSO format the targets included more than exoplanets, were multiple filters, with color transformation  and included a check star.  Certainly, all of this is not required for the AAVSO format.  However, that is what I assumed from your original post and that is what I prototyped. I may have made a mistake this assumption.

Perhaps your goals are more limited.  If so, please take a look the RedDots campaign at and the video tutorial  Also note that the required AAVSO format requested was updated in the 6/28/17 post (#11) here  While not a clean tutorial, you probably can piece together the info to do the conversion from these resources.

I suspect we will hear more about exoplanet observing and data format/storage at the fall AAVSO conference given the focus of that event.

Hope this helps,


Log in to post comments
AAVSO 49 Bay State Rd. Cambridge, MA 02138 617-354-0484