From: "Terrence R. Redding, Ph.D." <tredding@mac.com>

Date: July 20, 2009 12:52:33 PM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] First light 16" Truss Dob Jupiter imaging


That is very impressive.


Here is a smaller link to the same image.


http://tinyurl.com/mowc5q


Terry - W6LMJ - 14.287 


Terrence R. Redding, Ph.D. RTN

Redding Observatory South, West Palm Beach, Florida

http://olt.net/learningstyle/Site_2/Learning_Style_Research.html

How do amateur astronomers learn?



On Jul 20, 2009, at 2:13 PM, Milton Aupperle wrote:

Hi Jim;

On 20-Jul-09, at 5:42 AM, jimchung2338 wrote:

> Hi all,
>
> Firstly, no images of the impact disturbance since it was facing
> away from me this morning.
>
> http://tech.groups.yahoo.com/group/Astro_IIDC/files/Planetary/
> TrussDobJupiter.jpg

It would have been just setting. From what I can determine it's about
+ 90 to 100 degrees from the GSR's edge. I got clouded out, but even
at 3:45 am when Jupiter is at it's peak, it was only 22° above the
horizon anyhow and the Jet stream is over top of me again.

> A few months earlier I had fantasized about planetary imaging with
> a light bucket on a budget like a 16" Lightbridge. You could have
> decent image size and high capture rate to freeze seeing. As it
> happens, a local observer was selling his 16" truss dob sans optics
> for an unbelievable price as he was moving up. I found an old 16
> f4.5 Meade Starfinder dob mirror which I had locally recoated and
> also sourced a used secondary. The second part of the equation is
> building a rudimentary tracking platform since its pretty hard to
> nudge this beast of a scope and keep it centered on a small 640x480
> chip. Due to the method by which I've attached the drive motor to
> the platform there is a degree of occasional fine tuning of the
> motor speed to keep the image centered so its busy but doable. And
> since I only eyeballed the polar alignment of the platform, every 5
> minutes or so I need to adjust the DEC/Alt by tapping the truss a
> few times with my knuckles!

Very cool. I can't wait until you get it polar aligned and all dialed
in. Your moon shots will be interesting too :)

>
> Here's what it looks like:
>
> http://tech.groups.yahoo.com/group/Astro_IIDC/files/Other/
> TrussDobPics.jpg
>
> Jim
>