Autoguiding with an imaging camera

[prasadka]

Hello folks,

Is it theoretically or practically possible to use the imaging camera for guiding, by perhaps adding an extra imaging chip? Perhaps would be a sophisticated set up, but will probably do away the need for a guide scope and an additional guide cam- hence easier perhaps? Is this astronomically(?) difficult to achieve?

Cheers,

Prasad

[Kaptain Klevtsov]

Yes, on both counts.

http://www.sbig.com/sbwhtmls/special_production_st4000xcm.htm

Is a camera with a built in guiding system, Starlight Xpress cameras can use (I think) the main imaging chip for guiding, and you can self guide using a webcam whilst shooting a planet.

HTH

Kaptain Klevtsov

[MartinB]

As KK says, many SBIG cameras have a seperate guide chip built into the main camera which gets around the disadvantages of a seperate guider. The main disadvantage is lack of flexibility choosing a guide star esp at long focal lengths and when narrow band imaging. Superb system though.

The "budget" camera is the ST7 which comes in at around £1600. Ian King is currently offering with a free motorized filter wheel. The ST2000 has a similar size chip to the SXV H9 for around £2400 which isn't too bad when you remember you don't need a guide scope, all the extra mounting gear or a guide camera. With the addition of a motorised filter wheel (which is far more useful than you might think) it starts to look a good competitor to the H9 http://www.iankingimaging.com/show_products.php?category=45&offset=10&offset=20

SXV developed a system called star2000. As I understand it this continually samples part of the chip (alternate lines which swap with each sample run). The down side of this is that because at any one time half the chip is being used for guiding exposure times are doubled.