https://www.schneideroptics.com/pdfs/filters/FilterTransmissionCurves.pdf is an actual chart from an actual filter manufacturer. Linear scale, not log scale, but you can see the cutoff of the UV filter at around 380nm. I am a little surprised that the lens cutoff is at 430nm, but you never known. Different lenses will be different. Skylight filters give a little warming. People like skin tones to be a little warm, instead of a little cool. As for digital or not, there is one important case: you want circular polarizers with digital cameras, though maybe also later film cameras. The AF system on some might also be polarization sensitive, but mostly the optical low-pass filter based on birefringence is polarization sensitive. It might be that some are labeled as digital for that reason. Other than that, it shouldn't matter.