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View Full Version here: : Scotch Mount (StarTracker)


middy
23-04-2006, 11:31 PM
I recently completed a project to build a scotch mount so I could take some widefield sky shots.

Attached are some images of the StarTracker.

The mount was loosely based on this one:
http://www.astunit.com/tonkinsastro/atm/projects/handscotch.htm

The wood was from some offcuts I'd had lying around for some time now. Add a few nuts and bolts, a hinge etc. from the local hardware shop ( < $10).
A bubble level ($3).
A lid from an old Milo tin.
The ball and socket mount was the most expensive part of the whole thing at the princely sum of $27. :scared:

The angled mount that the bolt threads through was a mistake. I thought I'd bought a flat mount and didn't notice until I'd already measured and drilled the hole and affixed the mount that it was in fact angled. :doh: So it changed from a tangential drive to a semi-isosceles drive. Luckily it didn't affect things too much according to my calculations. :P

Attached also are a couple of images taken using the mount:

Southern Cross: 10 x 64 s @ ISO 100
Omega Centauri: 6 x 48 s @ ISO100, 8 x 48 s @ ISO 200

Stacked in Registax.

I am quite pleased with the results so far given that it has been quickly cobbled together and the hinge has a bit of side play in it. It has been recommended that brass hinges are the way to go, so one day I might swap it over.

You hand turn the bolt at a rate of 1 turn/min. The length of the bolt gives me ~ 24 turns before I have to wind it back down again.

RAJAH235
24-04-2006, 12:18 AM
Andrew, tis amazing how good the images turn out with these simple devices. Well done. :thumbsup:
Oh, btw, why not try only turning the can/handle 1/4 turn, every 15 secs or so.. does not have to be continuous.
Now for a longer lens...... :poke:
ps. Recommend 2 x 2" brass hinges for your size. My boards were a little wider, so 2 x 3" were a tad better.

fringe_dweller
24-04-2006, 01:00 PM
Love scotch/barndoor mounts, even tho i have never built one - collected plans for them off the net and from mags for years but never actually made one lol :P
And with stacking/dslr's they are coming into their own again I feel - as you have amply illustrated Andrew
Thanks for posting this brilliant in its simplicity alternative to bought mounts.
there are really a no excuses for not having tracking now
cheers! :)