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Bill Weir
September 16th, 2020, 06:33 AM
I’m guessing more than a few here have one. Lately I’ve been pained manually switching filters and I’m beginning to feel a slide is in my future. Searching on line it appears there are really only two manufacturers, Astrocrumb and Moonlight. I’m looking for honest opinions if you actually use one. Pros, cons, which one you have? I only know one person with a slide and have never actually seen one in action. We have identical Starmasters and he uses an older Astrocrumb. He likes it but that’s a sample size of one.

Bill

Mark McCarthy
September 16th, 2020, 09:59 PM
I have used the Astrocrumb on my 20-inch. I like it a lot for the convenience; I can easily switch between various filters to compare the effects, which is really nice on planetary nebulae. It also acts as a focuser baffle. Something to watch out for, if you have a fast scope, is the blank opening might be a little too small and vignette your light cone (you can check with Astrocrumb for dimensions where it would sit relative to your focuser board so you can estimate). In most cases it's just a little bit, probably not noticeable. Consider getting the version with the dew heater, especially if you have a short UTA.

wvreeven
September 16th, 2020, 11:16 PM
I have a 2" filter slider for my 20" as well. Sorry, don't remember the brand. I've had it for over 5 years now. And I love it. It saves so much time switching filters which is wonderful.

Bertrand Laville
September 17th, 2020, 05:34 PM
Hi All,

You will fine some details here: http://www.deepsky-drawings.com/moyensmoyens/filtres/dsdlang/fr

One thing more: I preliminary used a 4 filters Astrocrumb filter slide; the result has been so interesting that I switched for a eight filters slide.
But in that way, the weight of the slide becomes heavy, and, to prevent the risk of a droping when you point close to zenith, it's better to install a security.

Bertrand

obrazell
September 18th, 2020, 12:19 PM
I use Rogers Mark II heated slide on both my Obsession UC's. It is the four filter version so not too long. There is some light path obstruction but not much.

Owen

Dragan
September 18th, 2020, 02:16 PM
Hi Bill,

Another vote for Astrocrumb. I have one of Rogers filter-slides on my 25. To be totally honest, I don't use it very often BUT when I do, I'm glad I have it. It's always worked exactly as intended. Zero complaints.

Bill Weir
September 18th, 2020, 11:20 PM
Thanks all. The only part I worry about with these slides is vignetting the light cone with my f/3.3.

Owen, with the Mark II how much past the front of the draw tube does it protrude.

Bill

obrazell
September 21st, 2020, 01:51 PM
Hi Bill - sorry for the delay in replying but I was off at a small star aprty. Poor skies we think because the wildfire smoke has now reached the other side of the pond. Amway the way the Mark II works is that there is a small ring that screws on the front of the focuser tube, perhaps about an inch long but I need to measure it, and then the filter slide fits over that. I would imagine with something as fast as your scope that some vignetting may well happen. I don't see any with mine but then it is F4.2

Owen