DIY spectroscope (spectrometer)

A DIY spectroscope of my design. The design is fully parametric (in Autodesk Fusion). I am using these two particular lenses I happened to have (but you can use many other lenses, just need to change parameters in the Fusion file - and the whole 3d design will adjust, and shrink or expand as needed):

- Collimator lens: an old SLR 50mm f/2.0 lens by Ricoh
- Camera lens: a C-mount 12.5-75mm f1.2 zoom lens (https://www.bhphotovideo.com/c/product/889132-REG/computar_M6Z1212_3S_2_3_12_5_to.html); I am using it at the widest end (12.5mm), so you don't really need a zoom lens. It just needs to be fairly fast, and very importantly - should have a focusing ring. An aperture ring would be useful, but not a must.

My camera is a cheap B&W C-mount astrocamera ToupTek, but many other types (DSLR etc) can be used. You can even use a webcam with a built-in lens (so no camera lens is needed), but that would require some redesigning. Generally speaking, B&W cameras are preferable as they don't