RE: [APML] Reworked M27

["Brian Lula" <brianl@polytecpi.com>]

Hi Jeff,

I took a deep image ( >1 hour at F/5 with my 20") of M27 last year with L and RGB filters and I 
did not see a trace of this outer shell. I took a 30 minute Ha shot of M27 a couple of weeks ago 
and the outer shell was definitely there. I also did the Crescent in Ha ( 60 Minutes) and the 
Crescent and surrounding region was simply awash in background nebulosities too. I haven't had 
a chance to work these images yet into an RGB but it is simply amazing at what an Ha can do. 
I suspect Rob's IC1396 would have been even better with a long Ha exposure for his luminance 
and R frame but it does certainly does take more time to get a good SN ratio and those long 
imaging windows have been fleeting up here this summer.

Take care, Brian






On 3 Aug 02, at 15:02, Jeff Ball wrote:

>  Thanks so much for the explanations, Roland.  I guess if there ain't no
> blue and green in the outer part, it's gonna be Halpaha red (whatever
> color that may be<g>.)  Wonderful picture.  Some of these images take a
> while for my expectation to be readjusted.  I love it when an old
> familiar object is painted differently.  Hope to join you with something
> different, soon.  Thanks again.
> Jeff Ball 
> 
> Basically, I chose a combination of Red and Ha for the red channel, then
> used Ha for a 40% Luminance. The end result might be a bit overpowering
> but this is because the blue and green fall off very rapidly at the edge
> of the "normal" nebula, and the Ha dominates in the outer part.
> 
> Roland Christen 
> 




Brian Lula
Polytec PI, Inc.
(508) 832-3456

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