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3D "Tragos" design

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Anthony Rodda's picture
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Last seen: 2 days 15 hours ago
Joined: 01/09/2014 - 14:15
3D "Tragos" design

Hi Guys,

 

I have this working on the bench.  It's essentially the Tragos layout using a Star Analyser 200 as the grating.  I've had to make do with a 4 degree wedge prism (instead of an 11) so the placement and dispersion aren't quite maxed.

 

But good enough to warrant further investigation.  I need to do a little work inproving focus mechanism and the rgidity in that the outer tube is a collection of focusers and pipes used temporarily to get the placement, etc right but the 'final' tube is very solid and I have metal adapters to suit.

 

The calibration lines are neon onto an Atik 314E.  (Note the 'E', not the best pixel ratio).  I know it's not properly focused but it was just a quick exposure.  But those lines are reasonably straight and the dispersion is quite linear, which was a surprise.

PS, blue to the right...

 

Notes from the CAOS team suggest that with a 23um slit (in use here) the resolution should be 350+.

 

Which isn't bad for an optical train costing les than ~ £200.  Add another £60 for an OVIO slit and guide mirror/lens.

 

To be continued...