The maker of my CCDSPEC (Ken Elliott) has been servicing it – he has installed a new mirror and slit and sent me photos of test spectra.
He sent me following message on 18/8/2019:
From: Kenneth Elliott
Sent: 16 August 2019 10:44
Last night I had some success with your CCDSPEC on my 150mm f/5 refractor with M57 the ring nebula.
I attach both FITS files and some JPEGs .
The first file is M57 seen on the slit but not going down the slit aperture. This was a 10s exposure with your QHY6
The second is th FITS file of the same
the next is the spectrum which is 10 minutes, but all but the first minute was cloudy, so its amazing you can see the nebula at all
It shows the sky subtracted spectrum too
The lines are H beta 4861 [OIII] 4959 5007 and H alpha 6563 and [NII] 6584
this is probably only a couple of minutes data
the other stuff is moonlight and light pollution
I’ll try and get some better data if we even get clear skies but it does look very promising.
First image shows M57 Ring Nebula off the slit:
Following screenshot shows the ring nebula & slit:
Following screenshot is a spectrum of the Ring Nebula taken with my CCDSPEC:
And in the following spectrum, the spectrum of the surrounding space has been subtracted from that of the Ring Nebula to leave the spectrum of the Ring Nebula: