2000mm FL on an EQ6 ?

[laser_jock99]

is this feasible or practical?

[Earl]

it can be a struggle over 1000mm unless you have the patience to get balance and PA and have a good EQ6.

Its not impossible as some have done it.

[ronin]

8SE is 2000mm FL.

And they go on a single arm Alt/Az mount.

However I assume you are not really thinking of an 8SE OTA, otherwise you would not have asked.

As we ask many of the beginners "Need to know the scope". :grin:

[johnrt]

A lot is going to depend on what scope we are talking about, you might be able to get away with it on a more compact OTA like an RC, but perhaps not on a reflector which will act as a huge sail in any kind of breeze that wafts past. Either way it's going to be tricky, if not perhaps impossible.

[dweller25]

If your talking about a 150mm F13.3 refractor it will be too much for an EQ6

[swag72]

Tim has managed it - His winning M1 from a couple of years ago was taken on an EQ6 with a C11 I believe.

As said, it very much depends on the type of scope you are going to be using I would think.

[laser_jock99]

Tim has managed it - His winning M1 from a couple of years ago was taken on an EQ6 with a C11 I believe.

As said, it very much depends on the type of scope you are going to be using I would think.

Was thinking about a 10" RC scope

http://www.telescopehouse.com/acatalog/Revelation-10--RC-Optical-Tube-Assembly-OTA.html

[swag72]

Was thinking about a 10" RC scope

I'd hate to say yay or nay - Is there no one on the forum that has that similar setup that can help? I have a mate with an 8" RC on an NEQ6 and he's struggling with it. I have an 8" RC on an Avalon (Similar to EQ6) and it's coping fine. I would say that 10" is probably pushing the envelope a little.... but no more than my opinion

[Earl]

ID say its doable but will take alot of fine adjustment to get reliable long subs.

[johnrt]

I have just looked at the Altair website and apparently the weight difference is 14.6kg carbon and 15.7kg metal tube on a 10". The 8" is 7.8kg carbon and 9.6kg metal tube. With an OAG and no guide scope adding weight you just might be able to pull it off.

However good luck finding a guide star with an OAG at 2 meters focal length, if you haven't already got one I could try and find mine - it's somewhere in a nearby field after I lobbed it over the fence in frustration. Evil things.

[swag72]

To be honest, I never had a time with my OAG and C9.25 at 2.35m focal length where I didn't find a guide star - So I don't think that will be the issue. But the accuracy that you will need with your guiding will be testing I would expect.

[Astroscot2]

 Hello, would you be intending to use that scope at F8 for imaging ?  The reuducer would take you down to 1340mm F5.6. If you are intending to use the reducer why not get the AAS Quattro for your existing scopes which would get you near 1410mm (f4.7) on your 12" F4 newtonian?

Mark

[wuthton]

I've just started playing with an 8"RC on an NEQ6 (imaging at its native FL) which is doable but I've torn a fair bit of hair out, I'm not sure I'd fancy any more focal length.

My QHY5-II just isn't up to an OAG at that focal length so a Lodestar (hardware binnable) is on my shopping list.

From my few days of experience at 1.6m I can say that with anything but excellent seeing focus and guiding is a PITA.

[Astroscot2]

Yes focusing at longer focal lenghts is an eyeopener.  when your used to imaging with fracs and lenses with small FWHM numbers.

[ollypenrice]

I don't think this has much to do with weight, nor, strictly speaking, with focal length. The real thing is to look at your proposed values in arcseconds per pixel. This defines your image resolution and, therefore, the guiding finesse that you need.

The EQ6, worthy as it is, is a crude old lump and of very variable quality. It's brilliant at short FLs for imaging and guides out well. For visual it will carry big scopes. How well it will deliver high precision guiding is anybody's guess. Clearly it can be done and, as Sara says, Tim did it - but Tim also chose to move on to a 10 Micron mount.

I like stuff that just works and would not put a 10 inch RC with that kind of FL on an EQ6, but that's just me. It isn't an assertion that it can't be done, just an assertion that I won't be trying it.

Olly

[laser_jock99]

 Hello, would you be intending to use that scope at F8 for imaging ?  The reuducer would take you down to 1340mm F5.6. If you are intending to use the reducer why not get the AAS Quattro for your existing scopes which would get you near 1410mm (f4.7) on your 12" F4 newtonian?

Mark

Or even the 1.8X ASA Barlow Corrector

http://www.astrosysteme.at/eng/correctors_newton.html

Mind you at 1188 Euro's it's not the cheapest of accessories!

I'll cobble together a 2000mm FL 'guiding experiment' with a bog standard standard 2X ED Barlow lens first to check the feasiblity.

Otherwise it sounds like I might need to re-think this project from the mount up.......

[ollypenrice]

Or even the 1.8X ASA Barlow Corrector

http://www.astrosysteme.at/eng/correctors_newton.html

Mind you at 1188 Euro's it's not the cheapest of accessories!

I'll cobble together a 2000mm FL 'guiding experiment' with a bog standard standard 2X ED Barlow lens first to check the feasiblity.

Otherwise it sounds like I might need to re-think this project from the mount up.......

'Mount up' is by far the best way to think...

Olly