Focal reducer for F/6

[MishMich]

Anybody have any advice on focal reducers? I'm looking for one I can use on my F/6.3 Onyx 80 ED refractor (equivalent to Equinox) and on my F/6 Orion Optics SPX 200. I was reading somewhere that reducers for SCTs don't work well with refractors, but most of the discussion seems to be around F/7.5 EDs. I want to shorten the focal ratio on both the Newtonian and have the option of using this on the refractor as well. I can image up to Pleiades comfortably on the Onyx, but with the SPX I am just managing to squeeze it into the DSLR frame. On the other hand, the Onyx - which easily spans M42 & the running man, or the Andromeda Galaxy - could benefit from being a bit faster (until I can get my rig better setup with Synscan, a firmer base, and properly aligned). 10 Megapixels gives some room to play with - and I quite like setting objects against the darkness.

Thanks,

M.

[davew]

As no one else is having a go.........

The simplw answer is yes. If you mount your camera via a push fit adaptor you can get either a 1.25" or 48mm reducer to screw on the end. Quite what your image will look like I'd hate to guess. It may not even come to focus on the newt. They seem to be designed for visual or webcams.

You mention 3 designs of reducer that confused me at first and this brings us to the point of the problem. Differing designs of scopes have differing problems to overcome. Some reducers made for very similar scopes don't seem to work on each other.

The newts often get used with a Wynn reducer. Then the secondary size is enlarged and the primary brought up the tube. Neither cheap nor easy.

Unless there is a new and very cunning device out there I think you would be better off getting the right reducer for each scope. Some one out there must know. If you don't get an answer soon try phoning FLO and ask them.

Bet that doesn't help. But I tried

Dave

[MishMich]

Yes. It does, thanks. It answers why I can't fit one on the Newt, and I don't think that having one on the Onyx is necessary (although looking at my latest images in more detail, I can see it would benefit from a flattener).

The sense I have with reducers is that unless the scope is specifically listed, you have to buy one and try it out, as nobody knows what will work with what. 'Try it and see' is not a good enough reason for spending that sort of money. I'd like some sense of whether spending that money will help me achieve what i want. If not, I'm no worse off not buying anything.

I think that I'll forget it for now, and make do with what I have. I'll keep using the ED 80 for some things, and the SPX 200 for others, and get the alignment and tracking sorted out with the upgraded Synscan so I can do longer exposures with the existing focal ratios.

M.

[davew]

I think you're quite right. It is too expensive to be the group tester. If you can find some one to lend you a reducer then fine.

Just to let you know, the TS flattener seems to work with the Onyx quite well - http://www.cmoos.de/astro/qhy8/cirrus_[L]RGB_2c_sat_vig_us_cut_50.jpg

That's a mosaic using the flattener. Have a close look and see what you think.

D Hinds were the importers I think. Give them a call perhaps ?

Good luck

Dave.

[davew]

Damn, the link hasn't come out right. Copy and paste. Sorry mate.

Dave

[MishMich]

Lot of stars in that one! Looking at the more recent shots with the Onyx & EOS 350 was interesting - but I couldn't make out what he was saying about it all...

Good idea, I got it from Hinds after all. So far he's not come up with much info on this. When I tried to find a shoe to replace the gunsight with a red-dot finder he couldn't help. I ended up getting a skywatcher shoe and drilling it out myself to attach to the scope. Cost a fiver +p&p when others said I'd need to buy a new finder for fifty quid, yet were vague about whether it would actually fit - oh, there I go again, moaning about retailers...

M.