Motor Drive for Dob?

[Episkey]

Is it possible to track using a motor drive with a 6 inch Dobsonian? I'm fairly interested in taking deep sky images, and would need tracking for my Dob. I don't want to go out and buy another scope yet, so does anyone have any recommendations for tracking with a Dob?

[umadog]

Not really unless you make an equatorial platform. Buying one will cost more than the scope. An equatorial mount may make more sense but it may need to be substantial for a 6" Newt.

[Capricorn]

The other point is that a dobsonian mount is a form of Alt/Az and not best suited to long exposure astrophotography (deep sky imaging).

[cantab]

There are tracking Dobs, but field rotation still limits subs to a minute or so. You can get field derotators, which basically physically rotate the camera to compensate for the field rotation, but then you've got three motors involved - alt, az, and field derotator - any of which could introduce blurring by being "not quite right".

[spaceboy]

So in theory EQP and dob has more of an advantage for imaging ?

[ollypenrice]

I think you would be very lucky indeed to get anywhere in DS imaging with anything other than an EQ mount. EQ platforms are not intended for imaging, with the incredible accuracy required. They are intended for visual observing and for this they are great. Sure, if you trawl the net you'll find someone who does 10 minute unguided subs on an EQ platform with a Dob... but then you'll find he's a millionaire electronics engineer with thirty years' experience of amateur telescope making.

It really is as simple as this; for DS imaging you need a good equatorial mount.

Olly

[Episkey]

Thanks guys. I guess I'll wait and get a better equipped telescope later.

[spaceboy]

So in theory EQP and dob has more of an advantage for imaging ?

EQ platforms are not intended for imaging, with the incredible accuracy required. They are intended for visual observing and for this they are great. Olly

Sorry Olly. I never convey correctly what I am thinking. I meant as far as dobs go. In theory if PA accuracy can be improved on, an EQP & dob would offer better tracking/ imaging potential over an auto AZ mount due to the way the different styles of mount track the celestial object.