Orion Adaptive optics

[gregbradley]

I see Orion have an adaptive optics unit.

http://www.telescope.com/control/astrophotography/astrophotography-accessories/orion-steadystar-adaptive-optics-guider-for-astrophotography

Only downside is it only handles APS sized sensors or smaller.

So DSLRs, 8300 chip, 3200ME chipped cameras for example.

Greg.

[multiweb]

Looks like a nice unit but for the price difference I'd rather look at the SXV-AO. I also read on CN somebody having trouble getting it started (Something about the guider head and support) and I haven't found many people using it. Regardless of the AO the SX Lodestar is THE guider. You wouldn't guide on faint stars at high frame rate with a QHY5 or rebranded SSAG IMO.

[marki]

They are about to release a version which has a motorised camera rotator built into the adaptive optics unit. Could be interesting if it all works and Greg there has to be some advantages for small chip owners ;).


Mark

[Bassnut]

Yes, despite the price all up, its an interesting bit of kit going by the spec. Having the AO, rotator and OAG all in one is an obvious killer, if it works.

The back focus that an optec rotator, AO8, MOAG and adaptor farm from hell I have is rediculous and severely limits the OTA it can fit on, id pay a premium just for the reduced backfocus it offers.

Marc, why do you think the QHY5 would be unsuitable?. Which guide cam then would OK, a video type cam?.

That it handles only an 8300 size chip is fine, most monster chip WFW's wouldnt need AO.

[multiweb]

I have a QHY5 - you get reasonably bright stars at 1s exposures. At long FL with the OAG I needed to go to 2s to pick anything. The idea of AO is to image at long FL at the highest frame rate possible so you can do a minimum of 3 corrections per second to compensate for mount errors. And you need at least 7 corrections per second to correct for the seeing. Now I know by experience a QHY5 won't cut it. The SX Lodestar is supposed to be very sensitive even at high frame rates so it makes sense to use one IMHO. Now thinking along those lines why not get the whole SX gear rather than a half assed system 50/50?

[Tandum]

Are there any drawings for the oriion device? The ones I've seen for the SX device indicate that it's made for OSC cameras. Sticking a wheel in front of the camera on the SX device would put the guide camera about a foot in the air ...

[gregbradley]

That is interesting about the SX Lodestar. Do you know what chip it uses?

Is it CMOS or CCD?

I had a Starfish guider which was 1.3mp CMOS and it would do a few times a second. They need a buffer built in to get such fast rates as even though the camera may be able to take that many frames you have to get them downloaded as well really quickly.

I use an ST402ME for a guide camera on an Astrotech 66ED scope which works well but could use a bit more focal length.

For that purpose I just bought a Vixen VMC95L to use as a guide scope as it is light (4lbs), compact and 1045mm focal length. Also has easy straight through camera whereas my Astrotech needs a diagonal which is another weak point for flexure.

Greg.

[Hans Tucker]

The SX Loader uses Sony ICX429AL 8.2 micro monochrome CCD.

[bert]

Greg, does your st402me have an i2c socket? If it does why not use an ao8/aol on a mmoag? Then there is enough room for a large sensor.

I personally use the A08, and I dont understand that more people dont use adaptive optics considering the improvements in image sub quality that I got from its use.

Brett

[gregbradley]

Hi Bert,

am not sure what i2c socket is. Is it like a 9 pin socket?

I don't think it has, it only has a usb 2 port.

I never thought an AO8 can be used with a 402ME and a MMOAG.

That could be useful.

So how does that work? The AO8 just before the MMOAG or after it?

Greg.

[pmrid]

I have a small nit-picking issue with the Orion AO unit and the same issue with their Deluxe OAG. The guide camera mount is attached to the body of the unit by the usual means - it sits on a shaft that runs up from the internal pick-off prism. The issue is with the actual way the guide cam unit is secured to that shaft. There are 2 grub screws. Yes, they're nylon tipped and all that but only 2 and not 3 of them. With my deluxe OAG, I have found that the guide head is not as rigidly secured as I would like. When I have the time I plan to have a third hole driilled and tapped for another grub screw just to give me that bit of additional rigidity.
I wrote to Orion in the states and was told by them that they have not had any other comlaints about this and no returns because of it. So it may just be me and, as I said, it's a nit-picking issue anyway.

Peter.

[bert]

Yep 9 pin socket. The same socket as in the photo of the ao8. Adaptive guiding goes before the oag in the imaging train so the corrections form a hysteresis loop.

With my setup I do not use a oag as I can use the internal guide chip on my st4000xcm, because it is one shot colour, I do not have light loss due to filters.

[ericwbenson]

Guys,
AFAIK, SBIG AO can only be used with internal guide chip or the remote guide head, just the way the software was written. Of course there isn't a good reason why any camera with a very fast download of a small subframe couldn't be used, but the AO "trigger" is generated by the SBIG main imager then transmitted to the AO unit via I2C.

EB

[riklaunim]

For guiders you could try a focal reducers mounted in filter cells (1,25"). They will reduce the focal length for the guider making much easier to find a star at low exposures - but you need backfocus for this.

[multiweb]

Well, my SXV-AO (http://www.starlight-xpress.co.uk/SXV-AO.htm) is in the mail now. :evil: Watch out for those clouds :whistle:

[JohnH]

Congrats Mark! With the Lodestar I assume? Do report back here on how you get on with it.

[multiweb]

Yes - I have the SX-lodestar coming separately. The plan is imaging at F/10 on the C11 with that new keller corrector I bought. Haven't had a chance to check it out yet but probably this long week-end.