Lidl Skylux black tube = spectroscope

With the Bresser Skylux scope bought last week at UK Lidl Stores came
a Barlow-like tube that isn't! It contains centrally a simple lens to
invert the view in lieu of an expensive erecting prism. By adding a slit
[razor blades] and trans grating converts it to a simple spectroscope as
posted at

http://www.astroman.fsnet.co.uk/rainbow2.htm

I've used a Rainbow Optics grating but a section from a transparent CD may serve as a grating.

Nytecam