Planetary camera for guiding?

[Andrew*]

Would there be any disadvantages to using a Sony 445 chip planetary camera such as a Point Grey Chamaeleon as a guide camera?

[riklaunim]

Technical none. Practical - it doesn't has ST4 so you would have to use RS232-Computer connection to guide. Also it's not that easy to use Chameleon in PHD (you have to play with extra FlyCap 1.X installation to get WDM driver for it).

[Andrew*]

Cool, thank you! The mount would anyway be computer controlled so I don't think that's a major issue, but are there ST4-equipped cameras that do a decent job at planetary. I'd rather not buy two you see!

Sorry, what is a WDM driver?

[riklaunim]

WDM is a type of windows generic drivers for cameras. PHD can use it to get image from cameras and guide. There are newer ASI with ST4 or QHY IMG0H but I don't know if I would use those. The ASI should work best of the two (but no cooling if you would want it).

[Steve 1962]

I've used a QHY5v as a guide camera - both using the ST4 and pulse guide, and I now use my DMK21AU618 - both have always worked a treat. So subject to what Rik has said about WDM, I'd say that provided you're using a guide scope rather than an OAG you'll be fine.

[Andrew*]

I've used a QHY5v as a guide camera - both using the ST4 and pulse guide, and I now use my DMK21AU618 - both have always worked a treat. So subject to what Rik has said about WDM, I'd say that provided you're using a guide scope rather than an OAG you'll be fine.

Hi Steve, sorry for being thick, but what's wrong with using an OAG? Is it the size?

[Steve 1962]

Hi Andrew

I didn't mean to imply that there's anything wrong using an OAG - it's just that I've been told by very well known and reputable supplier that an OAG really needs a dedicated sensitive guide camera and a "normal" planetary camera might struggle to find a guide star.

I've never tried an OAG - it's just that I know the cameras that I've used work very well with a separate guide scope (I use a William Optic ZS70).

Also I've just remembered that I also used an unmodded SP900NC webcam as a guide cam for a while, so almost any webcam / planetary camera will work.

[Andrew*]

Hi Andrew

I didn't mean to imply that there's anything wrong using an OAG - it's just that I've been told by very well known and reputable supplier that an OAG really needs a dedicated sensitive guide camera and a "normal" planetary camera might struggle to find a guide star.

I've never tried an OAG - it's just that I know the cameras that I've used work very well with a separate guide scope (I use a William Optic ZS70).

Also I've just remembered that I also used an unmodded SP900NC webcam as a guide cam for a while, so almost any webcam / planetary camera will work.

That's a relief, thanks.

I have done OAG before with an Atik 2HS, a mono CCD with probably similar sensitivity to the 445 chip. I didn't have any issues finding a guidestar in the Orion region with an f/7.5 scope. A lot depends on the focal ratio of the scope.