Colormap on/off option in vanilla Doom?

A long time ago I had a demo WAD showing how somebody created a foggy outdoor area, but a regularly-lit indoor area all in one level. I just dug up an old, old, old 1-level TC (yes, TC) of mine and I want to do this but I'm not sure how. I'm wondering if he had a special colormap or a special lightlevel he used to do this.

The colormap I'm talking about is what color dark rooms and objects "fade" to. IE when you have a room with a light level of 96, it applies a certain amount of black to darken it. I've replaced this black with grey so when dark rooms fade out, they fade out to fog, not darkness. However, I have an indoor/underground base that I want regularly lit, but right now I have to keep it at 255 or else I get fog indoors.

Anybody know how to do what I'm talking about?

(...anybody know what I'm talking about at all?)

Yeah, that's part of the colormap lump.

There is a utility used to edit colormaps, can't remember the name, but you can edit the fading effect to some extent I believe.

I'm sure it has to do with light levels, like lower than 160 and fog effect is done based on how you edited the colormap lump, above and no fog (like full bright essentially).

I do have a program called InkWorks, however I couldn't find an option like the one you described. Back when I had the sample WAD, I did look at it's colormap in that program and there was nothing different in the colormap setup that I could tell. I may have an early version or maybe the utility you're speaking of is a different utility. Or it may be hard-coded, but I have no idea how to change that manually.

Yeah, InkWorks is the proggy.

If anything can be changed, it's with that. I haven't had much luck making a descent colormap though. The BOOM util does a wonderful job for blue/red/yellow/green colormaps.