Re: [APML]: My First OAG Deep Sky Photo

["Bobby Middleton" <bobbym@webwide.net>]

> 
> Brian Webb wrote:
> > 
> > 
> > I recently took my first off-axis guided, deep sky photo and it turned
out
> > rather nicely. The shot is of the Orion Nebula (M-42; it was taken by
> > exposing Fujicolor 400 for 5 minutes 00 seconds at the prime focus of
an 8-
> > inch Celestar SCT operating at f/6.3. No filter was used.

>From Rick & Melissa Keil
> I too took a shot of the Orion Nebula through an 8"SCT w/reducer using
> an OAG under very dark skies. My shot was for 20 minutes on PJM and it
> looked identical to your 5 minute Fuji400 shot. 

I've taken a couple of 5 min shots (was going to use to double-stack with
longer exposures)  
I've taken several 20-30 min shots. The gain is not all that great.
However, a 50 min shot
did show much more of the fainter fringe nebulosity, but the bright core
was washed out 
due to over-exposure. All this was on unhypered PJM. So I think you have to
push close to an 
hour to get the dimmer edge stuff on M-42. The ideal set-up for M-42 is one
long exposure 
combined with some sort of stacking/masking of a short (5 min max) exposure
for the bright 
core.

Bobby Middleton