So I just compiled what I thought would be the last compile, with a Full Compile- HDR Only. I really liked the lighting before, and I thought an HDR compile would make it even better.
But the lighting is much too bright, ugly, and gives me a nauseous feeling. So this is the question:
I don't want my elevator floors to be pitch black, but apparently you have to full compile the map to make them normal (which is working.) If I don't want to HDR compile it, then how do I make the elevator floor normal?

I would not recommend publishing your map without HDR, as HDR done correctly is much, much prettier.

HDR tends to be very bright on a early compiles. However, you can tone down each light individually on HDR only by setting the HDR brightness to -1 -1 -1 (brightness). Alternatively, you could use BrightnessScaleHDR and set it to something like 0.4, which will make your lights only 40% as bright as they would be when compiling on HDR.

Unless I'm mistaken (been a while since I've worked with elevator floors), the floor is pitch black not because of not having HDR, but because of vertex lighting - part of the elevator model blocks the light getting to the floor, making it black. If you really want to do a final compile without HDR, choose "HDR Full compile -final (slow!)", go to the $light_exe command and remove "-both". This will compile with LDR only.

Thank you for the help, but I have an small office area (which should be LDR) but the rest of the map is very large and open (HDR). How can I get a good balance between these areas? I will try compiling with these brightness values and see if my open area looks better.

You could also try changing the env_tonemapper settings. The global_ents.vmf one is named @tonemapper. I found that lowering SetAutoExposureMax decreases that glare. You can ent_fire it ingame to see the results. There are other properties that you can mess with as well. Just chuck the outputs into a logic_auto.

Before I start about HDR:
"Full Compile- HDR Only"
NO! A release should include LDR and HDR. The "full" just means your light_environment (if you have one, not used that often in Portal 2) renders a lot more light rays (see "-final" on https://developer.valvesoftware.com/wiki/Vrad#Effects ).

Now, before you ask any other questions here, read the following pages:

https://developer.valvesoftware.com/wik ... ing_Basics

https://developer.valvesoftware.com/wiki/Advanced_HDR

https://developer.valvesoftware.com/wik ... g_Settings