Anyway to get rid of all the light

I encountered a build that was pitch black except for a distance light coming from a door. I'm trying to build a photo studio where I can control the light with lighted objects. I built a closed box the other day and there it was still light inside. Anyway to get rid of the ambient light all together?

you can try making a black light-source.

For a photo shoot, you can set the Nighttime Brightness (in the Adv. Graphics tab of the Preferences) to 0.0, then force the sun to midnight. This won't affect what other people see in-world, of course, but it will get rid of the sun/moonlight for your snapshots.

Good tip there, but I swear I was teleported into a completely dark space where I could not even see my own Avie and had not changed any of my own settings.

Possibly you were teleported inside a solid black phantom prim?

Maybe you TPed to an estate that was set to midnight. Islands don't have to have a day/night cycle like the mainland. They can be fixed a particular time.

I also heard about that way... but as I recently digged for material about light parameters I found in the support wiki that black light in sl is the same as light off.

There are arguments back and forth on that all the time. To hear the Lindens tell it, the lighting system is entirely additive, and since black has a value of zero, adding black light to a scene does nothing. However, there are some residents who adamantly swear that when they set a prim to emit black light, it makes surrounding objects darker.

Personally, I believe the mathmatical answer. I have no reason not to since I've never seen this added darkness that a few people insist is there. I suppose it's possible that different video cards define the concept of black light differently, so maybe these people really are seeing something, but until I see it for myself, I have my doubts.

The inside of a prim is not solid, once you or your camera is inside it.

What I suspect happened here is the OP entered a place with rows of large, thin black box prims (possibly with a bit of transparency to them, possibly not) lined up close together. The Nakama sim has a train tunnel that uses this technique, if you want to see an example. As long as you remain facing the prims -- their non-thin sides, that is -- a very convincing illusion of darkness is created. Turn the camera ninety degrees, and you can clearly see the individual prims.

Now that I think about it, if you really want a good dark space, you might want to try making two sets of rows, each perpendicular to the other. I think this might preserve the appearance of darkness no matter which way the camera is turned, as long as it's kept roughly at eye level.

Oh, I just reread the original post, and should add a warning: doing this will make camera control very difficult, as the camera will hook onto the darkness prims. I DON'T recommend this for a photo studio. I once explored a photo studio that had prim beams of light, and it was essentially unusuable. Your best bet is probably forcing midnight and turning down the nighttime brightness.

I went to the source. Turns out I was TPed inside a Tube with its material set to "Full Bright" and color Black. Haven't tried this yet, but will.