2" filter wheel vs filter slider

[gaseous (Patrick)]

Hi all,

I've been toying with the idea of getting a 2" filter wheel or filter slider for my 16" collapsible dob. I've previously had a 1.25" filter wheel for my 8" dob with limited success due to lack of in-travel, which I'm currently revisiting with a few modifications. Do any of the clever people on this forum have any opinion as to whether a wheel or slide would be the better option for the 16", or whether both are a waste of time/money due to inherent dob focuser issues. Not really looking (at this stage) for a slider which mounts inside the OTA. Cheers.

[astro744]

Maybe a filter slide from http://www.astrocrumb.com/ is a better solution.

[gaseous (Patrick)]

Yes I had a look at those, and they look great but I could just see myself making a right royal mess trying to install it inside the tube, hence my initial reluctance.

[bytor666]

Originally Posted by gaseous

Hi all,

I've been toying with the idea of getting a 2" filter wheel or filter slider for my 16" collapsible dob. I've previously had a 1.25" filter wheel for my 8" dob with limited success due to lack of in-travel, which I'm currently revisiting with a few modifications. Do any of the clever people on this forum have any opinion as to whether a wheel or slide would be the better option for the 16", or whether both are a waste of time/money due to inherent dob focuser issues. Not really looking (at this stage) for a slider which mounts inside the OTA. Cheers.

If you only have a couple of filters, you could screw them onto extension tubes and then put the eyepiece you want to use in the extension tube and then rack it inwards.

Good if you have enough "in focus" travel.....not so good if you don't.

[billdan (Bill)]

Hi Patrick,

If you want a convenient way of changing one filter at a time you could use this 2 inch quick changer from Teleskop-Express.
You can buy additional filter drawers for use with pre-loaded filters

http://www.teleskop-express.de/shop/...terslider.html

Bill

[Merlin66 (Ken)]

+1 for the Neumann filter drawers from me.
I have the T thread attachment version with both 2" and 1.25" filter holders.
Great to set up the transmission grating and then switch over to the Cousins photometric V filter.
(Just one note of caution: With the Neumann 1.25" filter - the mounting thread seems to be at odds with a lot of the standard filters around, a bit of a hit and miss at times....)

[gaseous (Patrick)]

Thanks gents, hadn't really considered the individual slide drawer option - looks like it might have some merit.

[gaseous (Patrick)]

As a brief update, I ended up getting a 4 position filter slider from AliExpress for about $75 (from memory). It's got 4 x 2" holes, with 4 x 1.25" adapter inserts. In my 8" collapsible dob I need to lower the tube about 20mm to reach focus, but it works like a dream in the 16" dob with no adjustment. Very smooth movement, and much easier to remove the filters compared with an enclosed filter wheel. As the filters are exposed you need to be a little careful waving your arms about, but generally it's made filter comparisons and viewing a lot more user friendly.https://ae01.alicdn.com/kf/UT8o5aKX5...7b90eff20bac30