Basic Thea Render Lighting Question

I am just trying to understand the CORRECT way to light a scene in Thea Render with NO sun or atmosphere. Like a Museum with no windows.
Would using a couple point lights set to 50,000 watts or Would you use several spotlights with a large hotspot and falloff? I’ve had some success trying both options and enabling “ambient occlusion” helps a lot, but I can’t seem to get it just right.

I had to do a cave with a lot of rooms. It was a learning process but using lights with realistic parameters was the best. I added a few “fill” lights beyond the planned fixtures but they were low lumens here and there. “just right” can be hard.

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With Thea it’s pretty simple: you add the correct power for the light and adjust exposure.

Very low light conditions will have a lot of noise. Imagine you are in that cave and shoot a photo with your phone, lit by a single match… Probably the same thing will happen.

Thea calculates accurate light. It takes time.

Fill lights will compensate this noise but will create artificial lighting conditions that no longer represent the true light that would be emitted by the original light. They are there to create the right image, like photographs do when they use support lighting to take their interior photos.

I never used fill lights with Thea. I prefer longer renders and true to my designs light conditions.

Fill lights will also enable faster renders as they will help clear images faster.

If a nice composition is what you seek, do use them.

Nowadays I have denoisers so my objectives are achieved faster and people that want to create better looking and fast renders can avoid fill lights too, if they can afford the slightly added render time.


Thanks for the replies. I am getting some interesting results trying some different options,
using IBL illumination with no image but just a color: white and set very low power.
You then have to jack up the power on the lighting… but you get the desired result WITH a nice ambient lighting. I’ll post some images soon.
as for the noise… The denoiser in Thea seems to be doing a good job, making sure “Diffuse Depth” in the Presto Render settings is 0 as well.