[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]

Re: [APML] Prime focus advices for beginner

Hey Nicola,

--- Nicola <nmontec@libero.it> wrote:
> 1) Does the rule of thumb of the square of the focal ratio still
> apply like for
> telephoto lenses? That would be a nightmare as my scope is f/10 so I
> should at least expose for 100 minutes...

!00 minutes will be a minimum for most obj3ects. An exception would be
M42, where almost anything will show some detail. 2-3 hours is a must
really for even the brighter Messier ofjects like M16, M17, etc...
other exceptions wouls star clusters. You can usually start these at
about 10 minutes and work your way up.

Alan


__________________________________
Do you Yahoo!?
New Yahoo! Photos - easier uploading and sharing.
http://photos.yahoo.com/
_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo