Doing some photometry with Siril

One feature of Siril not very known is the photometry. Thanks to it, it is possible to accurately analyze the light coming from the stars. One good application is the exoplanet transit survey.
Indeed, when a planet crosses in front of its parent star’s disk, the whole brightnes of the star will drop by a small amount. This fall can be evaluated thanks to the photometry. It is also possible to compute some interesting values like the radius of the planet.

Here a small example in the following video how do we proceed.

And here, the result we did obtained with @vinvin on two exoplanets:



ow wOW! Awesome work on this.

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When I press the Light Curve button, a popup appears asking for install GNUPlot, but I’ve it installed and running from a shell prompt. I can’t find any configuration on SiriL to setup this program, so It seems to me that SiriL is looking for gnuplot on a path different that the one in which is available on my equipment. I’m running SiriL 0.9.12 on macOS 10.14.6 (Mojave) and gnuplot is installed at /usr/local/bin/gnuplot

Thanks in advance

Ok. Is /usr/local/bin/ in your $PATH env? (when you just type gnuplot in a console do you have the gnuplot prompt?)
Please try to make a symlink in /usr/bin just to check.

Yes, /usr/local/bin is in my $PATH. I’m able to run gnuplot from the command prompt.

I can’t create the symlink. Since El Capital (macOS 10.13), you can not touch /usr/bin without disabling System Integrity Protection (and I’m not allowed to do that).

OK. Need to test that on macOS.
How did you install gnuplot?

using homebrew, I made a vanilla brew install gnplot

ok. Will try to understand why.

Good news, the current development version (0.99.0, master branch on the repo) works fine: data is exported and gnuplot draws the light curve. Meanwhile 0.9.12 keeps failing. As 1.0.0 is close to release and nobody has bring this problem out before, IMHO we can ignore it and keep working on 1.0.0 :).