I often use an 80b filter on my lens when I do night traffic trail photography and since I have started doing that I haven't looked back from the days when I didn't use a filter at night. but indoors at night I find an 80b blocks out too much light and for some reason there is no tungsten balanced fast negative film.
In fact why aren't films like Portra 800 and Superia 1600 tungsten balanced as if you need that speed in daylight, I thought Portra 800 was for taking pictures indoors at night, no?

Anyway I was thinking of going down a compromise root of using a less blue filter that makes less of a correction and lets more light in,do many people do this?
Anyway I am not sure what filter to get, What I am confused about is that according to this an 80d only reduces the speed by 1/3 of a stop but increases the temperature by 1,300k but an 82b only increases the temperature by 300k but reduces the speed by 2/3 of a stop?