If I am rendering an image inside with no outside light source, ie a basement or in the current circumstances an underground cinema can I use channels 0 and 1 (Normally sun and sky) as controllable light channels to give me more flexibility? In other words in this model I have:
Ceiling lights
Wall lights
Table lights
Glow on some models
A galaxy star ceiling
A neon glow around the ceiling
Replies
Yes - you can put any lights in any of the 8 channels you want.
And you can put different types of lights in the same channel if that makes sense (e.g. ceiling lights and the sun can be put in the same channel)
(Except putting an individual light is channel 0 is "tricky" - see below)
Even with the sun or sky on, you could put other lights in their same channel. Also, many people prefer to put the sun and sky in the same channel, to free up another channel.
Default LIghting Channels
On the Lights SetUp tab, you can set the default channels for lights:
We separated ceiling lights and "other" lights onto two channels, because it makes the use of lighting channels for the casual user easier - (sun, sky, ceiling, other and glow are automatically placed in different channels)
If you set the default for Ceiling to 0, then ceiling lights and the Sun would be in the same channel.
Note:The default channels for lights, only apply to lights which have channel "0" selected when they are placed.
When placing this sconce, the specific channel for the sconce is "0", to it gets placed in the default channel for "Other Lights" - 2 as in the image above.
Placing a light in Channel 0
You cannot directly place a light in channel 0, since that would mean it would be placed in either 3 (if it was a ceiling light), or 2 if it was an "other" light.
So, to place a light in channel 0, you need to set the default for that type of light to 0, then any lights of that type will be placed in channel 0. And any lights of that type which you do not want in 0, would have to have a specific channel set when they were placed
(In your example, the easiest thing is to put self glow in channel 0, along with the sun and sky, and use the other 7 channels for lights.)