[skychart-discussion] USNO-A or USNO-B

[G. G.]

Often, I use catalogs USNO-A and USNO-B to identify faint stars. 
However, on many occasions these catalogs do not agree. Often, the 
difference is quite large (1+ magnitudes). Does anyone know which of 
these catalogs is more accurate?

Thanks,
Gennady