[HansSchulze]

I am stuck trying to find a super fast lens for nighttime, wide angle (60 deg) with a very low resolution (480V) small CCD analog TV sensor (1/2" or 1/3"), which on some calculators comes out to 4mm FL.
What is the limiting reason(s) that I can't have a 2 inch or larger aperture?
What about a larger lens (MFT, etc) hooked on an adapter?
How much aperture can be had for a ~five hundred bucks? I need many of them.
I was ridiculed that there was a F1/0.85 solution.. ???  I've scoured the internet for weeks.
Thanks
Sorry if this is too theoretical for this site.  I saw some great theory in the documentation here.

[Klaus]

A photo system lens seems to be a little bit of an overkill for your use case.

A C/CS-mount CCTV lens may do the job unless you have excessive expectations regarding quality?

e.g.
https://www.amazon.com/TAMRON-13VM308ASIRII-LENS-MOUNT-3-8mm/dp/B005YSK2F6
https://www.amazon.com/Megapixel-Low-light-Optical-Infrared-Security/dp/B07BN3TJ94
https://www.amazon.com/Baosity-CS-Mount-Network-Security-Surveillance/dp/B07JK86PF8