Hi Ken,
Yes, I know about the order prism-grating.
However, I was wandering how to increase dispersion on the setup (earlier w/o Tilter) by increasing the distance of grating from sensor, and found a discussion somewhere (when I find it again, I will post it here) that the order can be reversed (by mirroring the whole assembly), and indeed I tested this by making mistake (just reversing the order), see here:
https://www.iceinspace.com.au/forum/...6&postcount=19
My first results with this setup were on Sat night,
Nova Sco.
I am also thinking about slightly different setup, like on the attached image.
Basically, I want to convert f/10 beam to parallel, to avoid coma.
This will be my next project..