> Anyone know of active DIY higher-er resolution spectrometer projects using image sensors? Is it possible to create a sharp image of 940-1240nm 3000 pixels across with less then $3000 in parts? I want to learn how to make a broader(uv to ir) but crappy-er version of this: https://solarsystem.nasa.gov/resources/390/the-solar-spectru...

The linked project uses a 4000px wide image sensor and the second example in the article is a solar spectrum like what you want. It's not as sharp, but it's remarkably good given that the diffraction grating was a fragment of a DVD and the opening was a 3D printed slit.

940-1240nm isn't "uv to ir" like you described, though. That's just pure deep infrared. You'd have to test to see if the camera's image sensor was sensitive in those regions with any filters removed, but I doubt you'd get much signal in the deep IR region. Good sensitivity that far outside of the visible range requires a specialized sensor. Some security cameras designed for "invisible IR" will have such a sensor inside, so you could start by looking there.