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Sloan Filters - which ones?

ldj
Affiliation
Royal Astronomical Society of Canada (RASC)
Thu, 02/22/2018 - 13:17

I am planing to buy one or two sloan filters (can't fit a full set in my wheels!). Which would be the best ones to choose in order? My CCD is a KAF16803.

I am guessing g' then r'?

--- Dave LDJ

 

PVEA
Affiliation
American Association of Variable Star Observers (AAVSO)
Thu, 02/22/2018 - 17:31
Sloan Filters - which ones?

Hi Dave,

I mostly use my g' and i' Sloan type filters and the relation g'-i' (Covey et al. 2007) to obtain preliminary spectral type and Teff of the targets. With SG and SI you have got larger part of the star spectrum (from blue to deep red) and more reliable data.

Regards,

Velimir

HQA
Affiliation
American Association of Variable Star Observers (AAVSO)
Thu, 02/22/2018 - 21:21
Sloan filters

I agree with Velimir; the g' and i' Sloan filters would be my first choice.  For one, they have nearly identical exposure times for average stars, and as stated, cover a wide spectral range.  The g' filter is roughly the combination of Johnson B and V bandpasses.  The other filters are of course interesting, but you soon end up with a 10-20 position filter wheel and lots of invested money. :-)

Arne

ldj
Affiliation
Royal Astronomical Society of Canada (RASC)
Fri, 02/23/2018 - 12:46
Thanks Arne and Velimir. I'll

Thanks Arne and Velimir. I'll go with the g' and i'.