8 inch f10 cass for DSO astro

[SkysoBright (Jase)]

As per title. Will a 8 inch F10 cassegranian telescope be fine for DSO astrophotography work, or will the field be too narrow?

thanks

[Satchmo]

Jase , you can get an F10 to F6.3 tele-compressor lens which will give a C8 a more appropriate F ratio for astro-photography.

[Poita (Peter)]

You will need a focal reducer or if it is a celestron a hyperstar for most DSO's and you get a wider view and faster acquisition times as well.

[Poita (Peter)]

http://www.green-witch.com/steveloughrangallery.html

C8 plus hyperstar images

[RobF (Rob)]

It depends on:

- the actual DSO - won't work for Eta C, but great for M83
- Mount - you'll need at least an EQ6 probably
- Guiding - Need decent scope without flexure (or OAG)
- on your patience and expectations

[SkysoBright (Jase)]

no probs guys. thanks again for your knowledge. i might stick with the refractor.

this one seams like too much trouble... especially for a beginner

[wasyoungonce (Brendan)]

Originally Posted by RobF

It depends on:

- the actual DSO - won't work for Eta C, but great for M83
-....

Well not quite right....at F10 you'll need longer exposures and or more subs. I've done the keyhole at F10 just fine. FOV is quite small though so you don't get a sense of the whole nebulae.

F10 in general just needs good tracking and longer subs.

Of course a SCT like a C8 is a damn fine instrument as it can do F10/6.3 and F1.8 with hyperstar. Of course it's not easy to just change to Hyperstar but it can be done and make'th it a versatile instrument.

[RobF (Rob)]

Well, of course if you really like the full eta experience you could mosaic a stack of frames, but no-one is silly enough to do that are they?