Webcam guiding

[Carl]

Hi folks
I've got an old 700mm focal lenght refracter that I want to mount on to my C8 to use as a guide scope.
Any recomendations as to what webcam would be suitable for attaching to the guide scope and are the webcams light sensitive enough to pic off a guide star? I have an illuminated reticle to guide viewing thru the scope but I would prefer to sit at my computer instead of bending my body into an uncomfortable position to check guiding for long exposures.
I can afford a good webcam but not stuff like Mead DSI.

Regards
Carl

[PaulM (Paul)]

Hi Carl,
I was going to buy a Meade LPI (which is essentially a web cam), but after consulting with a few folks, I decided against it because in most cases the LPI isn't sensitive enough to find a suitable guide star.

Cheers,

[rogerg (Roger)]

Carl,

I use a QuickCam Pro 4000 to autoguide my losmandy setup through a 70 x 700mm refractor. I can guide on stars down to about magnitude 5.5 without a problem.

I use GuideDog (free software) which connects to the webcam & gemini, interpreting the image and telling the mount to make appropriate corrections.

The 70x700 guide scope is mounted in a set of 3 point rings so I can move it a good amount to find a bright enough star.

If I didn't already have the webcam (would've cost about $130) I would have probably spent about $250 on a second hand Meade DSI to autoguide with instead. You can't use the GuideDog free software with the DSI but you can autoguide some other way - search the forum, I think there are several previous posts about this.

Roger.

[[1ponders] (Paul)]

Or you could go for a long exposured modded ToUcam, that way you could guide on dimmer stars (lots of programs to use for guiding with a ToUcam) and then when it's planet imaging time your right to go for Saturn and Jupiter

[Carl]

Hi paul
Re your reply.
What is a long exposured modded ToUcam?
Regards
Carl

[[1ponders] (Paul)]

A normal ToUcam is restricted to an exposure of 1/5sec (http://www.pk3.org/Astro/index.htm?astrophoto.htm) but you can modify them yourself or buy one already modded that allows you to increase the exposure. Check out some of Ballaratdragon and Asimov's posts in Deepsky forum (or possibly equipment forum), they are both using a modified ToUcam for imaging. For a Webcam they do a damn fine job of deep sky imaging, but as a guiding camera they would be great. I use a standard ToUcam to guide with, but some nights it would be really nice to have that extra exposure time to be able to guide on those fainter stars. I guide with an Orion ED80 so it's not much bigger in aperture than yours.

[[1ponders] (Paul)]

You might find this page interesting as well http://www.pk3.org/Astro/index.htm?astrophoto.htm

[[1ponders] (Paul)]

This guy here sells the modded ToUcams http://www.telescopes-astronomy.com....am_philips.htm

Scroll down the page til you get to the heading.
PHILIPS ToUcam PRO II PCVC840K

[Geoff45 (Geoff)]

Originally Posted by [1ponders]

This guy here sells the modded ToUcams http://www.telescopes-astronomy.com....am_philips.htm

Scroll down the page til you get to the heading.
PHILIPS ToUcam PRO II PCVC840K

I've just bought a modded one for use with autoguiding, but haven't set it up yet. One of the problems I expect to have to deal with are the very short connecting cables (about 1m). Has anyone had experience with using extension cables--I've heard that too long a usb cable can cause problems with a ToUcam.

Also be aware that the modded camera adds about $140 to the cost.

[gbeal]

I use a ToUcam, which is unmodified, and K3 CCD Tools. The secret was good (Losmandy DR108) guidescope rings.

[Dennis]

Originally Posted by ghsmith45

One of the problems I expect to have to deal with are the very short connecting cables (about 1m). Has anyone had experience with using extension cables--I've heard that too long a usb cable can cause problems with a ToUcam.

I use a 3 metre USB extension cable and I haven't noticed any problems. I understand that you can use up to 5 metres before you need repeaters that boost the signal. Generally, I try to use the shortest I can usefully get away with.

Cheers

Dennis

[PaulM (Paul)]

I regularly use a 16 foot USB 2.0 cable with my DSI Pro and have had no problems.

[spearo (Frank)]

Hi Carl,
perhaps consider a modded Toucam. It's a webcam modified for long exposure.
i've used it on a spotting scope (used as guide scope) for a while which had 540mm FL. and you can adjust the lenght of exposure to better capture some less bright guidestars. Most times I have used it at the fastest 1 second exposure and had bright guide stars to use.

I've sold the spotting scope and am moving up to a william Opics 80mm for a guidescope and I will be using the Touacm on that one as well

PM me if you want to discuss further
cheers
frank

[Harpspitfire]

amazing website you have frank-- i noticed you have some unguided 9.25/DSLR images- what technique do you use to get the ASGT to track so well?- thx- john