M31- lens size?

[Harpspitfire]

whats the best f/l to get M31 (full frame) with a rebXT?--i got a canon lens 28-55mm, tamron 70-300mm and a WO66ED (400f/l) thx- john

[RB]

For M31 give your Tamron a go at around 200mm or more.

I got this shot (http://www.iceinspace.com.au/forum/attachment.php?attachmentid=14542&d=1152253570)with a 20Da and a 5" APO.
Also don't forget you'll need quite a decent exposure time to get good detail but it'll be rewarding.

I'd like to give it a try again with longer exposure.

:)

[Harpspitfire]

thx- ill try the tamron 1st- i tried last night with my SV80mm (480f/l) but found out with 30 second subs i just totally wasted my time- the moon didnt help, i wish that thing go somewhere for a years vacation- LOL