Color filters for all that stuff out there...

[Charlie in Dayton]

Waaaaaaaaaaaaaaaaaaaaaaaaaahoobledies.....

It were a great night out at the dark sky site. You could see all the leaves floating in the Teapot, the Milky Way was plainly visible, my new 130mm scope (aka HUb'ble III) was pulling detail out of Mars (hmmm...larger eyepiece + barlow = easier viewing than small eyepiece...how interesting...), and I was picking the brains of the local astrophotography experts. An extremely productive evening.

I was shooting the breeze (not to be confused with passing gas) with the club president, picking up some details on viewing filters. He threw me something and said to check it out. Turns out it was a sample pack from a theatrical gel filter manufacturer. Hundreds of colors, and each one had a paper tab giving specs including a graph of its spectroscopic blocking/transmission qualities. Just find the one you want, and hold it over the end of the eyepiece as you gaze...
The numerous intermediate steps available give lots of choices of just how much contrast to play with, and the availability of colors other than standard give much room for experimentation. I was impressed with the idea.

Here's a thread in a board that discusses the topic:
http://astro.umsystem.edu/atm/ARCHIV.../msg00617.html

This page discusses filters in general and their applications to astro-viewing...(I think I'm printing this one out for my stash of reference material in the toolbox...):
http://www.lpl.arizona.edu/~rhill/al...s/FILTERS1.HTM

I did a Dogpile search for "gel color filter sample packs", and got some hits. You may spend a couple of bucks, but hey, ya get large quantites of stuff...do a search with similar terms on other search engines and you'll get other hits:

($4.00 for a sample book)
http://www.alphasoundandlighting.com....95orless.html

(the website shows a sample book -- inquire about its availability)
http://www.tslight.com/stage/categor...r_filters.html

(an e-mail link to request a swatchbook of filters -- "Request a Rosco Swatch Book" -- and a listing with colors of some of the filters)
http://www.lighttrader.com/rosco_lux.htm

(for our brethren and sistern across the pond, this firm is located in Jolly Olde)
(firm's home page)
http://www.leefilters.com/home.asp
(swatch book page)
http://www.leefilters.com/LP3.asp?PageID=118
(here's the US homepage)
http://www.leefiltersusa.com/index.htm
(US swatch book page)
http://www.leefiltersusa.com/LightNewProdSWB.html

(this one gives the spectrographic info of each filter color)
http://www.gamonline.com/catalog/cinefilters/index.php

That oughtta be enough to keep folk occupied for awhile...[trundles off in search of that astrophotography exposure program John mentioned last night]...

[Charlie in Dayton]

Just for a giggle...the filter sample book from Lee USA arrived today...

I may do a little research here, seeing if there's some correlation between the standard Wratten filter numbers and the stuff in this swatch book. That way, you can have the standard filter, and maybe a couple gradations above and below the standard filter. Compensates for them there worn out rods'n'cones, don'tcha know...

[Charlie in Dayton]

The filter samples from GAMProducts arrived today. Again, each swatch came with a small spectral graph showing transmission qualities.

This has the makings of the first installment of a series on good stuff you can score off the web...

[engage Jimmy Olsen boy reporter mode]...

[Dickenmeyer]

Cool Charlie. I spent several hours observing Mars Saturday and Sunday evenings and played around with my filters while I was out. I have a basic set of Wrattens (yellow, green, blue, light red) that I ran through first, I actually liked the green best for bringing out the polar cap but Mars looks odd in green. Then I decided that it was bright enough to try my neutral density lunar filter and the results were actually pretty good for bringing out a little contrast. Then for laughs I screwed in my broadband nebula filter, it gave no real improvement to the view but didn't really impair it either, except for the wierd purplish tint.

[Charlie in Dayton]

Believe it or not, the two that seemed to work best for me were my Moon filter (about 14% transmission), and a variable polarizer (1% - 40%). Something colored didn't seem to do a whole lot, although I'm still learning what's supposed to work best on what. Further experimentation is called for.