I tried to mount a guiding camera but it didn't work: I needed some spacer to be able to focus both camera and I have to admit the off axis guiding module is very thin and doesn't leave lot of space for the camera. I do not really like the use of it but maybe once I got the right spacers, it will be ok...
Anyway, I played with Prism v10 software and acquired some images of CY Aqr, a pulsating (delta Scuti type) variable star. The screenshot below shows the run during the night. The maximum ADU count was measured inside a small box and without (auto)guiding, the star moved out of this box so the count dropped for some time. I moved the star back inside later on (well... I slept some time during those acquisitions!).
Prism software has a photometry module which is fairly simple to use (once I changed the catalog from GSC to GSC-ACT which is the one installed with Prism!). This module extract all the stars, look for the best references and map all the stars on a graph with magnitude & RMS. The stars should all be on a "main sequence" except the one which are variable!
I quickly looked at CY Aqr and result shows a very nice light curve, which can be improved by better selecting the variable stars and enlarging a little bit the measurement area:
Anyway, I noticed a star whose magnitude varies in a nice shape:
YES! This is a variable star which isn't indicated on Prism and the GVSC (Global Variable Star Catalog)!!! The star is GSC0567-1919. So I took images during an other night at OHP and a third night from home with the same setup. I sent the measurements to Raoul Behrend (managing asteroid rotation curves in Europe and variable star light curves) and Romain Montaigut (from CALA local club). They made some check and (unfortunatly) the variable is already known as VSX122414:
The light curve is very nice and this shows how to look at your pictures to search for new variable stars!
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