RE: [APML] New Tricolor

["Chris Schur" <cschur@cybertrails.com>]

Chuck, good to see a talented skyshooter such as yourself back to the list.
Nice shot, Looks like your ready for some of the more esoteric objects your
well known for.

Chris Schur

-----Original Message-----
From: astro-photo-bounces@seds.org
[mailto:astro-photo-bounces@seds.org]On Behalf Of Chuck Vaughn
Sent: Wednesday, August 27, 2003 3:15 PM
To: astro-photo@seds.org
Subject: [APML] New Tricolor


List,

It's been almost 2 years since I was able to take an astrophoto but I
now have a temporary setup at my new place and can take photos again.
What a joy it is to be able to walk out your back door, start a photo,
climb into your own bed for a nap while it is autoguiding away.

I haven't had time to update my web page so it's just a jpeg download.
This is the IC5068 region south of the Pelican. This is not my most
spectacular tricolor but it's more of an experiment with a new scope.

http://www.aa6g.org/Astronomy/Astrophotos/ic5068.jpg   (186KB)

Here are the details:

AstroPhysics 155EDF
Kodak TP2415 hypered
Custom RGB Filters
Exposure Times: R:G:B  90:180:180

These are the first exposures I've taken with the 155EDF since I bought
it used 2 years ago. I had done all the work to ready it for
photography but never had an opportunity to use it. I didn't know what
was going to happen. I'm very pleased with the image quality. The stars
are very tiny.

I decided to run the correct relative exposures unlike what I was doing
with the old 130EDT, which was to run three 180 minute exposures and
compensate in Photoshop by adjusting the green and blue exposures.
Compared to previous tricolors, the red exposure is about 1/3 shorter
and the green and blue are about 1/3 longer. When photographing
nebulas, I'm considering taking two 90 minute red exposures and
averaging them to reduce the overall grain somewhat. This could work
out fine, a 90 min red and a 180 min green on one night and a 90 min
red and a 180 min blue on another.

A surprise was that there is no vignetting in the corners of the 35mm
frame with this setup. I believed that to be impossible with a 35mm
camera body. The only thing that is new is a much larger corrector
lens. The OAG and the OM-1 are the same.

FYI: I didn't have time to hyper new film so these exposures were taken
on film hypered on Oct. 5, 2001 and stored in the freezer since then.
TP lasts a long time!

Notes on my new location... I'm 2 miles east of Mountain Ranch at 2500
feet almost at the top of a hill. The only easily visible light
pollution is coming from Sonora, which was a surprise, but my horizon
is about 1 degree in that direction. My west is blocked by a hill up to
about 10 degrees and I don't see much coming from the Central Valley.
So far, under stable weather, the morning low is only 2-3 degrees F
below the temperature at the end of twilight. The scope holds focus
very well. Nights are calm to very light breezes, almost more of an air
flow than real wind. There's quite a few planes on various routes so
I'm bound to catch one sooner or later.

Finally, I saw my first aurora on Aug. 24 at 0700 UTC. It went up to be
about 30 degrees in the northeast, moved around and then disappeared in
about 10 minutes. There was no color. It looked like light pollution.
:-)

Chuck <aa6g@aa6g.org>

_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo



_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo