Spectroscope

I bought a cheap spectroscope from Amazon. I kept delaying posting pictures, wanting to take better ones. In the end, I dropped it and now its spectra are skewed, so I'm posting the pictures I have, or I may never post anything.

I got a spectroscope because I'm interested in the properties of light, like: what's the difference between a yellow flower, and a picture of that flower on your computer? Why are the primary colours of light and paint different?

With a spectroscope, you can see the differences in "white" light. Sunlight is a continuous spectrum, and artificial lighting attempts to mimic that by mixing at least 5 colours. Electrical displays use RGB, but they're wider than I expected. It would be interesting to compare LED lit and CCFL lit LCD screens.

Previously, I had tried making my own spectroscope using a CD and cardboard tube:

Sunlight

Fluorescent light

LED screen

I would like to improve my spectroscope by making the slit width adjustable, maybe by using sharp metal edges and a screw mechanism.