Celestron C90 or C5 spotting scopes?

zamri · Post by **zamri** » Mon Dec 15, 2008 12:09 pm

Hi all very newbie in astrophotography. Considring to get my 1st scope.
Which to get between C90 and C5? I'm not intend to shoot professionally just a leisure shooters. Good enough if the scopes can go into deep sky, nebulae, jupiter, saturn and also comet images.

Any suggestion? Thanks in advance.

swat_pup6433 · Post by **swat_pup6433** » Mon Dec 15, 2008 1:33 pm

if you are a beginner in astrophotography, i would suggest you start off doing wide angle imaging with a lower Focal length scope for deep sky. besides. c90mak and c5. would both be a little too slow for imaging DSO without any mod. and also at such focal lengths, your mount and tracking would become really critical even slight winds might cause the image to trail. for planetary those would be a better choice since they have longer focal length. and also depending on the camera you would be using. a modified webcam? a DsLR? and you would require a fairly accurate tracking mount too.

zamri · Post by **zamri** » Mon Dec 15, 2008 2:08 pm

swat_pup6433 wrote:if you are a beginner in astrophotography, i would suggest you start off doing wide angle imaging with a lower Focal length scope for deep sky. besides. c90mak and c5. would both be a little too slow for imaging DSO without any mod. and also at such focal lengths, your mount and tracking would become really critical even slight winds might cause the image to trail. for planetary those would be a better choice since they have longer focal length. and also depending on the camera you would be using. a modified webcam? a DsLR? and you would require a fairly accurate tracking mount too.

Thanks for yuor reply.

You mean 1.2m scope is too much for me. If that the case what is the ideal focal length?
Is C65 mini mak ok, focal length 835mm?I'm using Sony A100 DSLR, can this scope be mounting if use T-mount adapter. It also come with table top tripod with slow motion controls.

swat_pup6433 · Post by **swat_pup6433** » Mon Dec 15, 2008 4:41 pm

for attachment to the scope. unless the visual back of the scope has got T tread where you could screw your T ring directly into. you would need a T adapter. which is normally T thread on one end and a 2" or 1.25" barrel on the other where you would slot into the "hole" which you normally would attach your diagonal or eyepiece. as for long focal length for planetary work. the resolution for most DSLR just wouldn't quite hit the mark. compared to a mod webcam capturing in video mode then stacking the frames together. and on top of that. the Focal length wouldn't be sufficient for your DSLR to do prime focus with, so you would need an eyepiece projection tube to work with an eyepiece and the camera.

for deep sky imaging, at focal length this long and focal ratio in the F10/ F11 region, it would be pretty taxing on your guiding. and exposure time required would be a little over the roof~ maybe you could look into smaller sized faster refractors with lower focal length. and a mount with fairly good tracking capabilities coupled with motors and controllers. or you can start off with a guidescope with your camera piggybacked ontop of it using a camera lens first.

zamri · Post by **zamri** » Mon Dec 15, 2008 5:34 pm

Ok noted. Thanks for the info.

Meng Lee · Post by **Meng Lee** » Mon Dec 15, 2008 10:17 pm

Well, do note that scopes for planetary photography and scopes for deep sky objects photography are very different because of the criteria needed for each type of photography.

My personal recommendation for each type in the lowest budget, yet will get decent will be:

1) Planetary : Orion 150mm Newtonian

http://www.telescope.com/control/produc ... t_id=09896

2) Deep Sky photography: William Optics 66SD

http://www.williamoptics.com/wo_shop/ca ... cts_id=325