[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]
Re: [APML] 7331 (again!)
Bobby,
You make some very good points. There are some I disagree with
however. There are HII regions in the CCD image that aren't even
resolved in Tony's image. Contrast does *NOT* equal detail or resolution.
In Tony's image the contrast has been dialed up to accentuate the dustlanes
but again contrast is no substitue for resolution. The detail in the
dustlanes
of the CCD image are far superior to that in the film image. Also there's no
blurring
at all. The smoothness of the CCD image is solely due to high S/N from
close to 4 hours of exposure time for the luminance. Tony's image is very
grainy close up
because of the relatively poor S/N compared to the CCD image.
Regards
Rob Gendler
Email: robgendler@att.net
Web site: http://robgendler.astrodigitals.com
----- Original Message -----
From: "Bobby Middleton" <bobm@koyote.com>
To: <astro-photo@seds.org>
Sent: Saturday, September 22, 2001 10:15 AM
Subject: Re: [APML] 7331 (again!)
> I can see better points for each image.
>
> Tony's film image has better detail of the dust lanes with more contrast
in
> them. To see this good look at the smaller face-on satallite galaxie's
dust
> lanes at above left of 7331. His stars also don't have the color saturated
> out. I don't agree with his final colors; I would darken up the image a
bit
> while stretching a little more (not much). I would also lower the green in
> curves just a bit. With these adjustments I like the color of the film a
bit
> better than the CCD image. Tony's image also shows the Ha regions much
> better.
>
> Rob's image is of course much better speaking in terms of grain, but
there's
> a "fuzziness" there not in the film image. Rob are you doing some kind of
> moderate blur? Still, with the grain of Tony's image, the CCD image does
> have a "smoother" look. And Rob does have some of the very faint mag
stars
> that Tony does not have; pointing to the sensitivity edge of CCD over
film.
>
> I personally feel that both images are close enough in greatness to leave
> the final decision up in the air. And with a good TP "L" shot, (or
> tri-color) the film image could easily surpass the CCD image in quality.
> Just my subjective opinion. Both are fantastic images!
> Bobby Middleton
>
> "God doesn't play dice".........
> Albert Einstein on blind chance
> http://www.koyote.com/users/bobm/astro1.htm
>
> ----- Original Message -----
> From: Robert Gendler <robgendler@worldnet.att.net>
> To: <astro-photo@seds.org>
> Sent: Saturday, September 22, 2001 7:42 AM
> Subject: Re: [APML] 7331 (again!)
>
>
> > Tony,
> > Really extraordinary effort and great widefield image.
> > Not quite CCD though. I think with the dimmer detail
> > CCD still outperforms. Again here is my CCD version
> > of ngc7331 for comparison.
> > http://robgendler.astrodigitals.com/7331.html
> > Rob Gendler
> > Email: robgendler@att.net
> > Web site: http://robgendler.astrodigitals.com
> >
> > ----- Original Message -----
> > From: <Tonyhallas@aol.com>
> > To: <astro-photo@seds.org>
> > Sent: Saturday, September 22, 2001 12:41 AM
> > Subject: Re: [APML] 7331 (again!)
> >
> >
> > > Hello everyone,
> > >
> > > Last night I used TWO HOUR hypered Kodak Royal Gold 200 @ 90
minute
> > exposures of 7331 (great test object) and recorded a LOT more than the
> > previous negatives. Tracking was very good, as was the focus this time.
I
> > "polluted" these better negatives with the original Picture Window
result
> > and came up with a new image and a close up.. you can see H II regions
and
> > galaxies everywhere... in the close up, the companion galaxy to the
upper
> > left even has two faint H II regions showing. As the signal to noise
ratio
> > is increased through PW more detail and color is showing up... almost
CCD!
> > :-)
> > >
> > > You can see these at:
> > >
> > > http://www.astrophoto.com/7331.htm
> > >
> > > and:
> > >
> > > http://www.astrophoto.com/7331CU.htm
> > >
> > > Tonight I am taking the LAST images of this galaxy in an attempt
to
> > repeat last night's results... then I will have four really good negs to
> > work from. This has been a real learning experience...
> > >
> > > Tony
> > >
> > > -- APML Archives at <http://astro.umsystem.edu/apml/> ---
> > > Unsubscribe at <majordomo@seds.org>
> > >
> >
> >
> > -- APML Archives at <http://astro.umsystem.edu/apml/> ---
> > Unsubscribe at <majordomo@seds.org>
>
>
> -- APML Archives at <http://astro.umsystem.edu/apml/> ---
> Unsubscribe at <majordomo@seds.org>
>
-- APML Archives at <http://astro.umsystem.edu/apml/> ---
Unsubscribe at <majordomo@seds.org>