[vsnet-chat 179] V vs v

[Berto Monard <lagmonar@csir.co.za>]

Dear readers,

I would like to touch on the possible discrepancy in the reporting
of visually observed magnitudes.
In order to do the correct thing we must use v sequences, not V.
How many charts have v sequences?

To avoid any misunderstanding on my side: I assume V is meant
to be photometric V ( = photopic response) and v is visual ( =
'mostly(?)' scotopic  response). B magnitudes originate from
measurements in the blue B-band as defined...
In general it can be stated that v = 0,6 V + 0,4 B. This means that in
the case of red objects v -V often > 0,5.

Question is, how should we go about it? If the sequences are
given in V and B we can convert them to v.  Is that practical?
Guidelines please!

Regards,

Berto Monard

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