dedicated astrophotography reflector

asimov (John) · #1 17-11-2005, 06:22 PM

Hi all.

I just finished turning my little 'toy' 4.5" newt into a dedicated astrophotography scope.

I use this scope rarely these days. It has a .965" focuser on it.

All I did was take the draw-tube out of the focuser altogether. It's just the right size then to slip the toucam & adapter into the focuser. Focus is rather crude: push it in or pull it out to focus lol. It will stay put once you spend 20 minutes getting perfect focus.

Tested it out last night on venus, it did ok.

All I really need to do now is drill & tap the focuser & add a set screw to secure the camera properly.

No pics. Imagine a little reflector with no draw-tube with a toucam hanging out of it.

Starkler (Geoff) · #2 17-11-2005, 06:49 PM

How will you collimate it ?

RB (Andrew) · #3 17-11-2005, 06:50 PM

Mmmm,

The new "Humble Space Telescope", I like the sound of that.

RB (Andrew) · #4 17-11-2005, 06:51 PM

Quote:

Originally Posted by Starkler

How will you collimate it ?

Ask NASA. They're experienced with mirrors.

asimov (John) · #5 17-11-2005, 06:58 PM

I spent quite a few hours making sure the secondary was perfect by using a home-made sight tube. Primary collimation I intend on using the toucam itself. I tried this last night, & the diffraction rings were easily seen.

RB (Andrew) · #6 17-11-2005, 07:00 PM

Yeh I would have thought it be easier to collimate with the ToUcam in place wouldn't it ?

I'm thinking of making something similar to that too, and keep it as a dedicated setup.

asimov (John) · #7 17-11-2005, 07:07 PM

May as well hey? I wasn't using this scope so may as well get the most out of what equipment one has. I'm not expecting top images from this scope, but it will be good fun to try to squeeze what I can out of it.

Thiink · #8 26-11-2005, 01:32 PM

Asi: I've been thinking about doing the same thing with my little 60mm DSE refractor! I actually had a go at some targets during the day this week with a $20 ebay webcam Ive had for ages with the lens removed (sticky taped to the scope) and it worked fine.. well until the webcam decided that it didnt like being pulled apart and stopped working.. :/

I might have to grab a ToUcam early next year when I have some money again and have a play around with it to see what the little scope can do (I might need a cheap EQ mount as well though..).

Wide field experts: would the 60mm refractor with ToUcam be enough for autoguiding for wide field on a big enough EQ mount?

gbeal · #9 26-11-2005, 02:19 PM

"Wide field experts: would the 60mm refractor with ToUcam be enough for autoguiding for wide field on a big enough EQ mount?"
I can't see why not. I use an ST80 (actually a Celestron Nexstar 80), so an 80mm f5 refractor.
If there is anything wrong with your plan it will be lesser light for a guidestar. Make sure you can adjust significantly the guidescope so as to find a suitable guide star, brightness wise.
With wide field, I use a 300mm or shorter camera lens, and with the lens or camera on a ball and socket. this allows a guidestar to be located, and then the camera/lens aligned on the target area.
Gary