Variable brightness star?

Similar to the case of the variable star I reported in June last year. The central star seems to be varying in brightness by comparison with the nearby galaxy, if you look at the individual cutouts… ???

Maybe I’m not looking at it right, but I’m not seeing obvious variability in the single-image cutouts – are you looking at the images within z- or r-band only? I do see some significant PSF differences which make the central brightness smaller…

Compare the relative brightness of the objects in these thumbnails. The one on the left (the red star I am referring to in the DECaLS browser) seems to have a different intensity in them, relative to the other objects? What would cause that?

CCD r 634766 S1, 82.0 sec (x,y = 330,1769)
(decam/DECam_CP/CP20170328/c4d_170329_011243_ooi_r_v1.fits.fz [25])
(observed 2017-03-29 @ 01:10:32.336850)
Look up in JPL Small Bodies database \ 100x100
CCD r 635131 S6, 120.0 sec (x,y = 1315,3458)
(decam/DECam_CP/CP20170329/c4d_170330_003508_ooi_r_v1.fits.fz [30])
(observed 2017-03-30 @ 00:32:19.026819)
Look up in JPL Small Bodies database \ 100x100

CCD z 725168 S5, 80.0 sec (x,y = 740,3693)
(decam/DECam_CP/CP20180224/c4d_180225_041441_ooi_z_v1.fits.fz [29])
(observed 2018-02-25 @ 04:14:41.272495)
Look up in JPL Small Bodies database

The first two of these are in r-band (you can tell from the “CCD r …”), and they look ~ the same brightness to me. The third is z-band, and yeah, way brighter there (hence the red color for this star).

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Aaaah! I just twigged how these thumbnails are labelled! Different filters - hence different intensity in some of the thumbnails owing to the colour of the star.

Well, I got there in the end… meanwhile I have been spotting lots of asteroids!