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William
Sounds like my next mission is to get the HOPS Software up and running for the upload capabilty. I think I will use the AstroImageJ to process the initial images,flats, darks etc and then load the resulting scientific images to HOPS.
Looks like I have even more reading to while away the cloud covered evenings – are we ever going to see stars again in North East England?
Thank you for your helpful comments
George
Thank you that is most helpful about the HOPS software and Python. LIke previous replies I have reservations about using such a fluid language which has a had at least one really big change and over the next 8 years could cause a similar break in support.
As I mentioned AstroImageJ would be my first choice and I have used it a lot on variable stars – hadn’t realised there was quite so much material for exoplanets. I have a lot of reading and cross checking to do. Am I right in presuming that the resulting lightcurve can be uploaded to the exoclock website or should I be thinking about processing via AstroImageJ and then uploading from HOPS software? Or I just need to do more reading!?
George
LibreOffice appears to be incompatible to Excel – the platform for the VSS macros? However the AIJ macro as it stands only needs your file structure to create a set of calibrated images ready for further processing. The next version will need a radec file which is an AIJ published format and can be generated by hand (with care) or use AIJ to mark the comparison stars and then “Export RA/Dec…” is a File menu item on the Image display. Once you have that the new macro will produce a Measurement file which needs to be processed. This type of text file is, I suspect, something similar to what you are handling now to produce the VSS input file?
Are you trying to invoke AIJ from within the LibreOffice environment? At the moment this macro is designed to work once AIJ has been started. Once the macro gets setup for your system it will run a long time but the results are well worth it. I am still developing the macro to handle the Multi Aperture analysis automatically as well. After that I going to look at invoking a version of Richard Lee’s spreadsheet to process the output Measurement file to produce the VSS input data file. A complete workflow automated once the radec file is setup for the comparison stars
This morning I noticed I had topped 25,000 images plate solved in the last 12 months – even with Northern UK weather! Like you I really had to develop a batch system. I’ll post the next version here soon.
George
I agree that it needs a larger venue and something more in middle England – Winchester is a long drive from the North! I enjoyed the Warwick University Meeting this year and it might well have the capacity?
Yes I am doing differential photometry and relying on the standard comparison stars.
To summarise – avoid median – non linear operation for stacking and this leads to exposures which should be recorded as the sum of the exposures in the stack. Because of the way I take the frames I will have the equally spaced exposures of equal exposure times the mid point of the central frame will be very close to the stacked observation time.
Thank you for your advice – newbies can get a bit lost on some of the details. Last year’s data was processed with Muniwin which did not require much in the way of decisions about stacking – however the down side was entering the locations of comparison stars, I felt this was very error prone. Richard Lee’s spreadsheet for processing AstroimageJ measurements file does this in a very slick way, hence my experiments with this approach. However stacking raised these issues which you have answered. Thanks again
