From: "Tim" <tjp314@pacbell.net>
Date: January 11, 2006 2:02:04 PM MST
To: Astro_IIDC@yahoogroups.com
Subject: Re: Eskimo Nebula image uploaded to files
Hi guys.
Thanks for the remarks. I think shooting at f/10 helped a lot. I made the tube for my
Jaegers out of old birdseye maple flooring that was in my shop when we bought our house
(on a rack, I didn't rip it out of the house!). I used plywood for baffles and structural
support. I get wonderful contrast in a dark sky with that scope, even though the coatings
are not in great shape (the lens is about 45 years old). On the Eskimo, I first tried imaging
with the Mogg FR in place, with the Baader contrast booster in behind the FR. But the
image was too small, and since the Tak was tracking so well without guiding, I decided to
try f/10. First, I took both the FR and the filter off, but the residual color was very
objectionable, such that I bet I'd get nothing but blue-appearing stars if I imaged that way.
But with the filter in place, the color is very good. I may have to upload that M42 mosaic
without finishing it, just to show you what I mean - it nocked my socks flat off, and the
exposures were only 10 seconds.
Last night was clear, but the weather is changing, so I wanted to image last night before I
couldn't for a while. I've got the high clouds again. When we get these Santa Ana winds
through the passes, it can get very clear, though it never gets truly dark. I've been able to
find Canopus over the skyscrapers downtown on a couple of occasions (we have a view
down the Arroyo Seco to the south across downtown (7 miles away) and all the way to
Palos Verdes penninsula about 25 miles away).
I recently "came into" another Jaegers lens and cell - this one a 6" f/15 - and a 12.5" full-
thickness f/3.5 parabola (that I was told was about 1/10th lambda). I just might try my
idea from before, where I mount the flea at the prime focus and not have a secondary
mirror. This one might need a paracorr, though. Does Televue still make those? Of
course, I'll have to go out of my way to build an OTA that has no provisions for an
eyepiece! ;o) ...and if it works well enough, I just might try one of the higher resolution
color Pt Grey cameras in it... hm...
-Tim.
--- In Astro_IIDC@yahoogroups.com, Milton Aupperle <milton@o...> wrote:
Hi Tim;
Nice image - especially considering your shooting from light polluted
LA.
Does the Baader Contrast Filter you used also act as a LPR filter too?
I've been either ice fogged in (lots) or clouded over here in
Calgary. And during my vacation to this exceptionally dark site (no
street lights are allowed in the village), the first two nights I
managed to get the scope all set up and drift aligned between clouds.
After that I never got to use my scope at all for the next 2 weeks.
TTYL..
Milton J. Aupperle
President
ASC - Aupperle Services and Contracting
Mac Software (Drivers, Components and Application) Specialist
#1005 - 815 14th Avenue. S.W.
Calgary Alberta Canada T2R0N5
1-(403)-229-9456
milton@o...
www.outcastsoft.com
On 11-Jan-06, at 8:58 AM, Tim wrote:
Hi all:
I uploaded an image I took last night with my color Flea, to the
files/DSO area. It's a grabbed
and averaged set of 3 60 second exposures. Shot at f/10, as the .
6x focal reducer made too
small an image. Unguided Takahashi NJP german equatorial mount
(love that polar finder!).
No darks or flats used, though i did use a lasoo selection tool
with a 50 pixel feather to
reduce the amp glow in the upper left corner of the frame.
I also began a mosaic of M42 that was looking spectacular, but as
Orion was dropping toward
downtown in the SW, the background sky color was changing to an
unpalatable dark green.
I'll tyr to finish that mosaic on another night.
best,
-Tim.