Simple camera to autoguide with

[rogerg]

Hi all,

I'm starting to try autoguiding on my portable setup. I've got autoguiding working very nicely on my LX200 with the SBIG ST7, but for the portable setup (Losmandy GM-8 (with gemini) ) I have never tried.

I don't want to use the ST7 for several reasons:
- it's permenantly fitted to the LX
- it chews about 2.5 amps
- it would need a combersom power supply converting 12v to 12 and 5v.
- it seems like overkill.

The portable setup is just a Megrez 80 with Skywatcher 70x700 side-by-side, the skywatcher being the guidescope.

I have a QuickCam Pro 4000 that I'm going to try autoguiding with when it's next clear, using GuideDog. But I suspect the QuickCam isn't going to be sensitive enough for anything but the brightest stars.

Assuming the QuickCam doesn't work, what's the easiest solution? Remembering the autoguider port on the older Gemini's isn't compatible with SBIG style autoguiding (without adaptor - US$100 ouch). Because of this, something like GuideDog is very suitable, able to simply control the scope through the normal scope -> computer cable.

I would like to stick to a USB, small and simple camera. I was thinking maybe Meade DSI, long exposure ToUCam, Meade LPI, Orion Deep Space or StarShoot camera? I'm not sure if anything but a webcam can be used with GuideDog. Also not sure if LPI or StarShoot are sensitive enough to consider.

I'm wanting it to be cheap too. Below $200 ideally. Second hand is fine.

Ideas?

Roger.

[[1ponders]]

ToUcam (especially a modded one) and Neximager will work fine with guidedog. I'm not sure about the LPI or DSI though they would be prefered.

[EzyStyles]

hi roger. I use a DSI for guiding and seems to work fine. ALthough you will need this adapter:

http://www.store.shoestringastronomy.com/products_gp.htm

to trick your GM-8 into thinking it is a LX200 so a LPI/DSI can be guided. It also supports guidedog.

[gbeal]

ToUcam (unmodded) for me, using an 80mm C&N achro. K3CCD Tools makes it all happen and works with Robbies StarMate.

[rogerg]

Any idea what magnitude stars you can guide on?

I'm sitting here trying this out right now with the QuickCam Pro 4000 and am having some success with being able to see stars, but can only see stars down to about mag 6.3 (obviously quite bright). I'm wondering if the ToUcam would give a significantly different result, I expect not but would be interested to know.

I am working with a 70mm, at about 700mm focal length. Hmm, could be hard to compare.

I think I'm going to need fainter stars, or guide scope rings that'll give my guide scope movement in both directions.

Roger.

[[1ponders]]

That mag sounds about right, certainly not much fainter than that. I use guiderings to get around the problem.

[rogerg]

Thanks, that's what I wanted to hear, that I'm in the right ballpark. Guide rings, yeah.. I can move my scope left andright relative to the other scope, but not up/down, there lies the problem. (I just have a slot in the mounting plate so I can rotate it). I'll investigate rings again.

Roger.

[gbeal]

Rog,
no idea of the mag. I have a flip mirror on the rear of the 80mm (I think it is 400mm F/L). In the top I have an old Celestron illuminated reticule eyepiece, and the ToUcam sits at the rear. I get the object on the chip, and then find a guidestar. YES, rings are the key here. I started with home made ones, but quickly got frustrated. I now have Losmandy DR105's, and they are the answer. It allows searching in a decent direction for a suitable star.