Comment on photo of M 13
https://www.facebook.com/photo?fbid=10218423746097042&set=gm.3821644861298049
I am looking at Aladin for M 13 and cannot match those pictures to yours. Can you point to and name some of the nearby stars? Which way is “up” What is the field of view (right and left RA and Dec would help
When I magnify your image, it has a lot of structure. That blue star that you have to the southwest of M13 at ra 250.26925814674
dec 36.20110100355 might be HD 150679 with these links.
Yes pretty sure. No way to send you a link to the view I see. You have to zoom out. It is to the southeast of M13 in RA Dec world. And the other stars begin to match. But I don’t have any way to overlay images even if I copy them.
That star that you have to the north is at ra 250.76759258663 dec 36.50967996144 is anothe variable star HD 150998 at http://simbad.u-strasbg.fr/simbad/sim-id?Ident=%402892709&Name=HD%20150998
I have to find the star in Aladin, match it by eyeball to your image, look up the Gaia RA DEC, go to Simbad and search by coordinates, then go back to Aladin. Faster than never but slow and hard on the eyes. I want to know how variable. I found that database of variable stars months ago, but have not used it. Getting too tired to remember everything. I think you need to rotate about 90 degrees counter clockwise to make it match closer to Aladin and Simbad.
That blue star has photometric rgb magnitudes of 7.031925, 7.253312, 7.362930 from Gaia release 3. I downloaded part of that database last night and learning its contents and methods. You could use several of the documented positions and spectra to calibrate your camera. Using several would make it easier. In principle you could use dozens or hundreds or thousands of stars and their mapped spectra and positions to map you any lens distortions, find your sensor response and register the image. That “plate solving” is maybe related, but I don’t know what software you used. With only jpg, those kinds of things are not worth doing. It needs lossless high resolution images. I tried to rent space in a remote camera, but too expensive. Just going to find and use all the online cameras and sensors and database.
Thanks for the nice photo. Zooming in, it is better than the posted images in the databases. But they are just for guides and what people could find. Too new to it, to know for sure what motivates people. The scatter on the surveys is crazy. I thought people would be methodical. guess they are, in their own way.
Richard Collins, Houston Texas
