I am resurrecting my SA100 spect grid, with probably a colour ZWO 1200 and I am looking for tips re scopes. This will be a dedicated spect scope sitting on top of a solar scope, so does being an achro matter?
I did the calculator on the r Spec website and a sweet spot for spectra was an 80mm f6.5 skywatcher - but it is rather expensive
looking for cheap and cheerful as I have to buy rings also
You can use the SA100 as an "objective grating" by drilling a 32mm hole in the centre of a spare lens cap and inserting the SA100 into that, then put the cap onto a 135mm lens. You will get lovely results, be able to take fantastic multi-spectra images AND no need to buy a scope etc.
Piggybacking a DSLR then means you can track, remove the SA100 lens cap and use the lens for widefield etc etc.
As for your question, no, spikes won't make a difference to your spectra.
Last edited by StuTodd; 06-11-2019 at 02:39 PM.
Reason: Spellinz
Graham,
The SA100 works well in any scope. Preferably f5 or greater.
No issue with spider diffraction.
Poor achromats can give rise to "fishtail" shaped spectral images. (See attached)
As you probably know, a mono camera will give better result.
Any other questions, just ask.
Stu,
No issue, the use of objective gratings is very popular, Uwe has shown some very good and higher resolution results used objective gratings.
The grating is very flexible......spectroscopy 101
It provides the opportunity of gathering Spectral data and practicing Spectral processing.
Check out our webpage for details and other ideas.