Page 1 of 1

Time series Photometry

Posted: 26 Dec 2018, 20:54
by Forum_2018

First, thank you for creating Astroart, it is such a nice tool for astronomy!

I am looking how to do time-series Photometry in Astroart. Time-series is a method where a long series of exposures are examined for variable stars or asteroids, to determine their rotational period.
Currently I am using AIP4WIN to do this, but it dosen't seem like AIP will be developed in the future.

The tools I mostly use is the Multi-Image Photometry tool.

This is the "starting window" of this tool, and this tool allows analysis of the star or asteriod under analysis, to determine if it has saturated. This is very useful

It is also possible to select to track the star or asteroid automatically during the series (useful if the target is moving due to own movement or if the image is drifting during to flex of badly behaving drive)
In the tool it is possible to output a report of the time series and prepare it for submitting to, for example AAVSO.
It is also possible to output different types of photometry, usually Differential is chosen (for my use)
When setting up the photometry run, a setup could be like this:
Notice the analysis window, where the rings for apertures are shown. Also, notice the image of the stars, where the first in the series are shown. The variable, V, Comparison, C1 og Check, C2 are shown.

After the series run finishes, AIP presents a window with a "Quick look", if something happened :
In this case a minima of an eclipsing star was succesfully detected.

The output file which is a basic text-file which can be imported in Notepad or Excel for further processing or submitting to AAVSO looks like this:
I have been looking for a tool something like this in Astroart, but haven't found anything like the tool in AIP, especially to be able to track a moving object..


Re: Time series Photometry

Posted: 26 Dec 2018, 20:55
by Forum_2018
Have you looked at batch photometry ?
And then you can use option "Follow minor planet" .

Re: Time series Photometry

Posted: 26 Dec 2018, 20:55
by Forum_2018
Hello Einari.

This certainly does some of the wished features.
I am missing an option to check out how the apertures are configures. It also seems like this feature only allows ensemble photometry, since there is no reporting of V-C1 and C2-C1 magnitudes. Also, the reporting is only in ADU'sn not in raw aperture magnitudes..
Not really useful, neither for variable stars or asteroids..
But a lot of the functionallity is there, so with a few modifications!!!

Re: Time series Photometry

Posted: 26 Dec 2018, 20:55
by Forum_2018
I agree it could be improved.
So for now I use mostly Fotodif software to do photometry.
AstroImageJ is another tool but it is just seems to be too 'scientific' approach for my taste.
Did use AIP4WIN too in the old days (the 'Book' was awesome).

Re: Time series Photometry

Posted: 26 Dec 2018, 20:55
by Forum_2018
Hi Einari.
I was not aware of Fotodif. Brilliant program. Unfortunately, i cannot find a manual ín english. Do you know of such ??

But yes, Fotodif do contain features Astroart could benefit from.

Re: Time series Photometry

Posted: 26 Dec 2018, 20:56
by Forum_2018
Hello Jens,
Sorry I don't know any english tutorials for Fotodif.
But it is pretty simple to use (and remember to use US format for separation & decimal points - otherwise it won't work - strange for Spanish software...).
Yet again, may I offer another possibility :D