Affiliation
American Association of Variable Star Observers (AAVSO)
Fri, 06/26/2015 - 18:25
Hello All.
I,m new in the Variable star scene, like to start with photo metric data collection.
I need to buy filters B-V , i guess , and yes 50 mm, looked arround did read a lot.
what i,m missing on the net is some comment (pro <> contra) about Omega Optical photo metric filters.
It looks there are 3 on the market (Custom Scientific , Omega Opticals, Chroma) Astrodon can not deliver, they say.
maybe can some folks some tips in this topic.
Met Vriendelijke groet.
Willie Buning.
Nederland.
Hi Willie,
What camera are you using ? If it's a unfiltered CCD astro-camera ok you need such filters, but if it's a color CCD or a DSLR it's not recommended to use photometric filters, just use the RGB channels and the proper transformation or VSF processing (in anycase a transformation is needed, the filters being only one aspect of the total response of the system).
Anyhow it's better to choose filters following the Bessell "photonic" definition. The original Johnson definition doesn't fit the present CCD and CMOS photon-counting response.
Clear Skies !
Roger
Hello Roger.
thanks for your attention. wich camera I use? its a SBIG 8300m camera.
I have all filters on 2 inch size, so iff possible also the photo metric filters.
bessel? euh... ?
groet.
Willie.