... It is 1st August, and you are hoping to observe a number of bright galaxies from a catalogue. ... You used the normal Vega magnitude scale. You now want to compare your B-K colour against the published colours of another, supposedly similar star you found in the literature. Your colour: B-K = 3.43 Literature colour: B-K = 3.41 Unfortunately, when you read the small-print in the literature paper, you found that the published colour used AB-magnitudes, not Vega magnitudes. ...

... Printed in U.S.A. THE STELLAR DISK THICKNESS OF LOW SURFACE BRIGHTNESS GALAXIES D. Bizyaev 1,2,3 and S. Kajsin 4 Received 2003 October 23; accepted 2004 June 9 ABSTRACT We present surface photometry results for a sample of 11 edge-on galaxies observed with the 6 m telescope at the Special Astrophysical Observatory, Russia. ... We find from a comparison of photometric scales that the stellar disks of LSB galaxies are thinner than those of high surface brightness ( HSB) galaxies. ... UGC 11301 .. ...