[Aavso-photometry] B-V from V-I

[Michael Koppelman]

Great, thank you.

An implicit question hidden in my question was: should this really 
depend on what kind of star it is? Do we start getting complications 
from emission and absorption on some stars or something? Seems like a 
blackbody should pretty well approximate most stars when talking about 
these fairly large bandpasses.

Thanks!

Cheers,
Michael Koppelman
http://www.lolife.com/astronomy/

On Feb 20, 2005, at 11:19 AM, Arne Henden wrote:

> For dwarfs, the relation is approximately
> (B-V) = -0.07 + 0.88*(V-I)
>
> In other words, (B-V) is usually slightly smaller than (V-I).