Good evening, dear observers. GAIA G magnitudes are currently very popular for faint objects, as this mapping extends very deep. However, for magnitudes in the G channels of DSLR cameras, wouldn’t it be more appropriate to use BP GAIA magnitudes? In the attached curves, you can see how the transmission of the GAIA G band corresponds more closely to the EQ of a CCD, which spans from 400 nm to 1100 nm. The BP GAIA magnitude, on the other hand, restricts the transmission of its band to something closer to the DSLR G channels, or even V Johnson. I’m referring to the magnitudes of faint objects, as I already mentioned.
I have found a transformation relationship from GAIA magnitudes to V Johnson, a bit cumbersome to have to do these transformations every time, but it is what is at hand, if several comparison stars are used the errors are minimized.
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I think I would have filtered the G(bp)-G(rp)[mag] point at around +3.5! 
The ESA Gaia documentation 5.5.1 gives even more interesting non-linear conversion correlations to the Johnson-Cousins system. I like them because they cover a wider color range. When observing with standard UBVRI filters, it’s the only way to use the Gaia data. Many older cross-correlations between photometric systems (like Johnson, Sloan, other) seem to be linear with narrower validity ranges or split into 2 linear sections with abrupt change above B-V colors of about 1, although I have to admit that redder stars are probably not the best choice as reference.
I just keep struggling to find well documented reference stars in the AAVSO maps around variables, which are close enough to the variable.
I’m also struggling to work out my color transformations as many standard fields also don’t have enough standard stars for good correlation.
So in both cases I tend to include Gaia stars with the above mentioned conversion correlations to Johnson V (or B or R)
Maybe time for an AI conversion model?
Tom