"mat_fullbright 0" Console Command Not Working

[Toxinom]

So as I start a new chapter on 'Black Mesa East' I constantly have the noted lighting problem. So I did a little research and found the "mat_fullbright 0" console command. I input it, but nothing happens. So then I just go and restart Steam but it still won't work. I then tried inputting it to the Steam Start-Up properties and still nothing.
I've also tried entering it with sv_cheats both on and off with no results. Any ideas?

 

[joule]

Known bug, as per this thread, with no real fix. However, Valve is aware of the issues the HL2/Ep. One engine update has caused.

Backstepper: Thank you. The Killsmith asks: ‘Valve has to be aware of the graphical bugs with the recent Half-Life 2/Episode One engine update: everything from screwed up skyboxes to missing facial animations to strange pseudo-HDR behavior. Will you guys be fixing these issues and when? We would like to play HL2 and the episodes again in their full glory before you release Episode 3 next month.’


Newell: (laughs) Ah yes, we’re going to fix them. When Erik [Johnson] gets he can be more concrete about the delivery date for that since he’s the one who would know. Yeah, we always are going to be keeping these things up to date and fix problems that either arise or that we create ourselves!

Newell: ... I want to go back to something we sort of touched on earlier since Erik [Johnson] is here. So the question is - there are two questions that I think you might want to address, one is the last Half-Life 2 update, what are the plans for getting the issues that we created fixed and out to customers?


Erik Johnson: I don’t have any data right off the top of my head on that right now.