Advise on equipment

[adamw]

I was planning on buying a focal reducer for my equinox 120ed for imaging with my canon dsrl. I was also thinking of getting an equinox 80ed pro (second hand ) with a guide camera. The plan being that I can then swap between the 80 and 120 using one for imaging and the other for guiding. The focal reducer would take the 120 down to f6.4 . Does this sound like a good set up and should I expect better/brighter images with the 120 at f6.4 than with the equinox 80ed ?

Adam

[laser_jock99]

I was planning on buying a focal reducer for my equinox 120ed for imaging with my canon dsrl. I was also thinking of getting an equinox 80ed pro (second hand ) with a guide camera. The plan being that I can then swap between the 80 and 120 using one for imaging and the other for guiding. The focal reducer would take the 120 down to f6.4 . Does this sound like a good set up and should I expect better/brighter images with the 120 at f6.4 than with the equinox 80ed ?

Adam

This sounds like a good plan- have two half decent scopes which you can swap between for imaging instead of just the usual 'naff' guidescope. The dedicated focal reducer for the Equinox 120ED is pretty much a must if you are using these scopes for imaging. The two scopes you are proposing are different enough to offer different fields of view especially if you can also aquire the focal reducer for the ED80.

The above set up is pretty much what I'm currently using in my obsy- though I'm toying with the idea of adding a third scope so I can run two imagers during those infrequent clear spells........

[adamw]

I think that is pretty much what i am looking at. How much does it weigh, i was guessing i would be looking at around 14kg with the reducer and camera's. What are you using to mount them both? I was thinking of using a dual saddle.

[ollypenrice]

Two questions spring to mind...

Firstly, would these scopes give you a sufficiently different field of view? The 120 has a FL of 768mm (reduced) and the Equinox offers 500mm. That doesnt really sound like two different animals to me. Down here we move in larger jumps, viz; 328mm (450 reduced), 450mm, 980mm, 2.4 metres. Sure, I'd like to add something around 700mm but it would be guilding the lilly rather than offering a genuine change.

Secondly the 120 reducer is also a flattener. Will the unflattened Equinox cover a DSLR chip without flattener? I don't know but I'd be surprised and I'd want to find out.

Olly

[laser_jock99]

I think that is pretty much what i am looking at. How much does it weigh, i was guessing i would be looking at around 14kg with the reducer and camera's. What are you using to mount them both? I was thinking of using a dual saddle.

My scopes are solidly 'piggy back' mounted - but there's no reason not to use a dual saddle.

Two questions spring to mind...

Firstly, would these scopes give you a sufficiently different field of view? The 120 has a FL of 768mm (reduced) and the Equinox offers 500mm. That doesnt really sound like two different animals to me. Down here we move in larger jumps, viz; 328mm (450 reduced), 450mm, 980mm, 2.4 metres. Sure, I'd like to add something around 700mm but it would be guilding the lilly rather than offering a genuine change.

Secondly the 120 reducer is also a flattener. Will the unflattened Equinox cover a DSLR chip without flattener? I don't know but I'd be surprised and I'd want to find out.

Olly

The 120/80 ED combination with SW flattener reducers would provide a selection of focal lengths from 900 thru 425mm (or 1.4 x 0.94 deg to 3 x 2 deg on say a Cannon 1100D). Shorter focal lengths and I'd be thinking more about camera lenses! Longer focal lengths is probably cooled CCD territory?

I can't find an example of un-reduced Equinox 120ED DSLR picture- but yes the SW reducers are also field flatteners.

http://www.firstlightoptics.com/reducersflatteners/skywatcher-focal-reducers.html

Also be aware that the SW flatteners are focal length specific- so you might need to buy both (unless anyone knows of a single alternative?)