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.