Focuser recommendations - FLI PDF / Atlas, others?

[naskies]

Not quite a battle tank, but on my way to building a hummer :lol:

I've been slowly putting together a 'budget' high res imaging system (image train now at 3.4 kg with rotator/AO/OAG/FW/camera), but my current MoonLite 2-inch SCT focuser is woefully inadequate.

I don't need to reconfigure the OTA + image train often, so I'm considering replacing the MoonLite with a focuser that can be screwed in and doesn't have a long draw tube, such as an FLI Precision Digital Focuser or Atlas.

Will the FLI PDF be adequate (I've read some negative experiences online about the PDF and heavy loads)? Is it worth saving/waiting longer for an Atlas focuser over the PDF?

Any other recommendations for focusers? Thanks!

[RockHound]

Hi

Not got a suggestion for a focuser but i am looking at how far forward the scope is being held on the mount and well :eyepop: it does worry me a little. Have you considered some sort of counter weight to attach to the front of the tube?

Regards
Paul

[gregbradley]

I had a FLI PDF for several years. I used to run a FLI Proline + filter wheel and MMOAG with guide camera on it. Thats pretty heavy. It worked like a dream. But the Atlas gets a lot of good reviews so if there is any question then the Atlas. Chances are you will be fine with a PDF.

Greg.

[DJT]

I have nothing on the focuser but have you looked at the losmandy weight kits that bintel have for SCT?

http://www.bintel.com.au/Accessories/Counterweights/Losmandy-Counterweight--br-DVWS-with-2-5lb/1253/productview.aspx

I have these on my GSO RC8 and I have a lot less kit. You have the space available looking at your rig for at least one set which should help bring your scope back.

[naskies]

What's worrying you? I'm genuinely curious... :question: The Losmandy dovetail of the RC8 is held very securely in the saddle. There's no possibility of it falling out - I've tested it with a lot of force (carefully).

I'll probably add some counterweights in the future to keep the primary mirror centred over the declination axis.



Yep, I've seen them. Very handy. There is a benefit to having the scope sitting a bit forward: I can do an inverted pier flip a bit earlier, go to bed, and let the mount track for a long time without automation software.

The position of the scope hasn't caused me any problems that I'm aware of... but I'm very happy to be corrected or informed otherwise!



Thanks Greg. I saw your PDF for sale ad a while back, but it sold while I was still umming and aahing over it :lol:

The Atlas seems great but it's quite pricey - it would be the single most expensive component in the whole system, by quite a large margin, so perhaps overkill for now. The PDF seems to be the smallest/lightest focuser that I can find that will be able to handle the image train without sagging or flexing.

[frolinmod]

The Optec TCF-Si or the newer FocusLynx compatible version is a good one as well if you have the backfocus to accommodate it.

I'm using an Atlas here. It's LOUD and sloooow.