andromeda @ f9

[libraryman]

Is it practical to image M31 with my 102fl Vixen @ f/9 ?

i'm sure i'll have a better chance with my f/4 reflector but i want to try the Vixen if i can.

what sort of subs would i need?

Ray

[AndyUK]

Hi Ray - Are you guided, or unguided... and what camera?

At either FL you have available I doubt you'll fit it all in though - Here's an example of M31 I took last year with a 100ED/f9 and unmodded Canon 40D (ISO 1600 - 60x60s, 51x120s and 132x90s, ISO 1000 61x90s)

[libraryman]

Hi Andy, guided useing a 350d, my mount is the capable Ci-700.

iv'e tried searching for a reducer for the Vixen and iv'e come up with the William Optics Flattener IV this takes it too f/7 but it's untried on the Vixen?

Ray

[AndyUK]

Hi Ray - I'm afraid I can't comment on flatteners as I have no experience of them (yet!), However,. to be honest, even at 700mm FL, you'll still be a little too close in for M31...

Still, as you're guided, you can obviously go for longer exposures than I did taking the above to get the extra detail in the outer part but obviously you'll need to take some shorter ones for the core (and then layer them in via Photoshop), but as to actual lengths, I'd only be guessing I'm afraid (sorry)

[libraryman]

No Prob's Andy thanks for the tips

Ray