Recommend me an Off Axis Guider

Nico13 (Ken) · #1 03-10-2013, 08:46 AM

Hi all,
Can anyone recommend an off axis guider for fittment to my GSO RC8 and used with an SLR for imaging please.
I will be also using my SX Superstar guide camera to fit to this.

Thanks.

Manav (Yugant) · #2 03-10-2013, 09:11 AM

I use a TS OAG and it worked first time. Saved me the hassles I had with my Atik one. Furthermore TS has good support so you can make sure you have the right adaptors if required. On a side note you have an SX camera maybe look at SX OAG as an option?

Nico13 (Ken) · #3 03-10-2013, 09:30 AM

Quote:

Originally Posted by Manav

I use a TS OAG and it worked first time. Saved me the hassles I had with my Atik one. Furthermore TS has good support so you can make sure you have the right adaptors if required. On a side note you have an SX camera maybe look at SX OAG as an option?

Thanks Yugant,

The TS is one I'd looked at but not the actual SX one's as yet as you tend not to see them advertised a lot so I will look at them as well.

Merlin66 (Ken) · #4 03-10-2013, 11:29 AM

Hmmm
using a DSLR limits the options, unless you have very good back focus clearances...

Poita (Peter) · #5 03-10-2013, 11:42 AM

The SX OAG is fantastic and very slim. I highly recommend it.

Nico13 (Ken) · #6 03-10-2013, 12:55 PM

Quote:

Originally Posted by Merlin66

Hmmm
using a DSLR limits the options, unless you have very good back focus clearances...

Yes Ken the RC8 has plenty of options for back focus adjustment with the addition or removal of spacer rings.

Quote:

Originally Posted by Poita

The SX OAG is fantastic and very slim. I highly recommend it.

Thanks Peter, I had a look at the SX unit on their web site, a nice looking bit of kit.

lazjen (Chris) · #7 03-10-2013, 02:05 PM

The TSOAG is good, but I'll eventually be looking for something better. I'm not 100% happy with the DSLR connector part of the component. It's not a firm as I would like, plus I dislike the screw-in holders for it to the other end (the bit that connects to the rest of the system).

I'm also going to look for something better as the prism shadows the image in my 6D. I'd like to go to an OAG that's 68mm (I think) instead of the 48mm I've got now to avoid this problem.

Merlin66 (Ken) · #8 03-10-2013, 02:24 PM

I like the look of the slide mirror/ OAG, I have a similar, but different unit on one of my guide scopes...works very well.
Large enough for full sized chips...
http://www.teleskop-express.de/shop/...urzbauend.html

alistairsam · #9 03-10-2013, 02:29 PM

I have the TS9 OAG and I really like it .
I believe Meru here uses the same OAG with his RC8 and has no issues with a lodestar.
to use the TS9OAG with a dslr, these two products are invaluable as they do not add the 10mm that a normal T2-EOS adaptor does.
so its just DSLR -> OAG and maintains the 55mm distance if you're using a coma corrector.
https://www.teleskop-express.de/shop...al-length.html

https://www.teleskop-express.de/shop...-TS-OAG-9.html

you can order the TS9OAG with a variety of camera end interfaces
T2, EOS, M48.
same with the telescope end
T2 or M48.

Cheers
Alistair

lazjen (Chris) · #10 03-10-2013, 05:02 PM

Quote:

Originally Posted by Merlin66

I like the look of the slide mirror/ OAG, I have a similar, but different unit on one of my guide scopes...works very well.
Large enough for full sized chips...
http://www.teleskop-express.de/shop/...urzbauend.html

No, that won't quite work for full-frame DSLR - it mentions it's OK for the APS-C though.

I'm just going to get something to directly attach to the back of the Moonlite focuser (or the tube I have attached to it). There's heaps of "width" available between the 48mm to 68mm portion of the view without impacting the full frame DSLR.

Merlin66 (Ken) · #11 03-10-2013, 05:28 PM

Chris,
The website says:
"Distance from prism centre to 90° T2: 46 ... 55 mm"
This would certainly clear the 24mm axis of a full frame sensor, and close to the 35mm size - the input and output ports seem to be "rotatable"

lazjen (Chris) · #12 03-10-2013, 10:15 PM

Hmm, good point and I just had a /smack-forehead type moment as I realised what I'm doing wrong with my OAG position (I think). I've had it horizontal to the ground instead of vertical, with it in parallel to the camera body. I know I can't get it vertical above the camera - the body won't allow it, but I don't remember ever trying underneath. I will be trying that tomorrow night.

gregbradley · #13 04-10-2013, 12:28 PM

I use an Astrodon MMOAG which is very strong and has grub screw holders which whilst strong mean you need Allen keys to get anything on or off.

It comes with 2 focusers both of them quite useless. I focus by loosening a tightening screw on a compression ring and sliding the guide camera in or out small amounts.

Its about 35mm-40mm thick including adapter. So backfocus is something you need to work out for your scope.

One thing with focusing if the guide scope is way off focus you won't even detect a star and it looks like no image was taken at all. When you are fairly close the out of focus stars become visible and fine focus is then easy.

Greg.

Poita (Peter) · #14 04-10-2013, 01:13 PM

You can borrow my SX OAG if you want to give it a burl.

Nico13 (Ken) · #15 05-10-2013, 11:47 AM

Thanks everyone for the comments and discussion it's turned out a great little thread with lots of thought starters

Peter I've sent you a PM re the SX OAG thanks, first class.