AO devices

[Bassnut (Fred)]

Im half considering going the AO route rather than a better mount for longer focal length imaging (or better guiding than I have anyway).

I have an AO7, but despite is raw speed, its just too difficult to use, and its image path is too long for a guiding-before-the-filters set up.

Im thinking an OPTEC motorised Pixus rotator (a rotator is critical IMO, its just too hard and disruptive rotating manually), an AO8 and an Astrodon MOAG, in which the SBIG external guider would go.

Its all fairly expensive unforch, but for AO imaging with 3nm Ha, guiding before the filter is necessary.

I cant recall anyone here with that set up, but some use the AO8 I think, how do you find it?.

Im fairly keen to find a cheaper way, I even thought the Meade derotator might do as a rotator, but I suspect it cant handle the cam/filter/AO8 weight.

Anyone with experience with before-the-filters AO with other ideas?.

[rally]

Fred,

Why not add a 2.7" Tak CAA - (Camera Angle Adjuster) and then buy a Takometer ?
These CAA's come up fairly often - I think due to upgrades to the large focussers.

Can't offer any comment on AO, other than to say that the AO investment should be considered with due regard to what size the next camera is going to be ?
If its going to be an STL11000 then the AO8 is too small.

Another consideration is that SBIGs AO's are also proprietory - they will only work with an SBIG camera.

Cheers

[Bassnut (Fred)]

Thanks Rally, yes, ive seen the Tak CCA, but just thought it was not for SCTs, but I guess that would work with appropriate adaptors, why not?.

Gegaapixel cams are a bit wasted with Narrow field, over sampling to that degree is an expensive luxury (and still image in NF without cropping), anyway I look at it, its hard to imagine a better alternative to the Hi QE ST10XME I have, and so also, any future cam is likely to be the same size format, the filter/filterwheel upgrade cost alone is prohibitive.

I dont see AO alternatives much better than SBIG for now, im happy to stick to SBIG, so the AO8 would do for the forseeable future.

[Doomsayer]

I would highly recommend the Pyxis rotator. I have a lead counterweight bolted to the SBIG tripod socket with a simple metal bracket . The weight balances out the CFW10 nicely, taking a bit of strain off the pyxis and preventing slippage due to connections unscrewing themselves. I also had a Pyxis-AP2.7 adapter made by PreciseParts which improved the pyxis connection.

I wouldn't mind an a08 either but a MOAG and the pyxis will not fit my current rig. I am considering making a narrower OAG than the MOAG to squeeze in an a08.

guy

[Bassnut (Fred)]

Guy

Great, its good to have some feedback on the Pyxis, thanks.

Make your own OAG, mm interesting, if you made it rotate, and fitted say a robo motor, that would be way cheaper than a Pyxis/MOAG, but then you already have a Pyxis . Iwas thinking of having a go myself, be interesting to see how you intend to make an OAG.

[rat156]

Hi Fred,

AO8 is better than AO7 because of the straight though path. Have you seen the new SBig's? They use both the internal guide chip and an external guider in an OAG at the same time...

Cheers
Stuart

[Bassnut (Fred)]

Yeah, I have Stuart, really cool to avoid flexure, but I overcame that at my FL, after a lot of work, bleedin obvious in hindsight, but doesnt seem to have caught on..........., anyway AO fixes anything like that, thats the next step and more, I dont think the new SBIGs do any better with AO, still needs a seperate AO device, no diff there. And yes the AO8 depth is appealing, hence the interest.