Barn door controls on area lights

[seandunderdale]

Is this something that has ever been discussed? I find that the effect of barn doors opening on a light in a real studio is something that is rarely achieved well in cg. Mostly because the tools to do it aren't the same. Maya spotlights lights have a barndoor feature, even if its really unhelpful that you cant see them in a UI. Mapping ramps to lights kind of works similar but I think you can tell the difference when watching studio stuff thats been shot vs cg lights with ramps.

[vlado]

Will make a note to look into that, but for the moment you can use the directionality parameter of the area lights to achieve a similar effect.

Best regards,
Vlado

[damaggio]

You could try and download the IES files from Arri lights for example and see if they work better for you and you can also download the real 3 light model to put the light source inside so the result can mimic better the DP lighting on stage.

[Joelaff]

I usually build or find a light model of some sort and let the barndoor geometry cast shadows for more realism. Geometry based light modifiers usually look pretty good, but they can be slower to render, especially when we are talking about things like grid spots, snoots, etc. The Directional Parameter Vlado mentions above is often a good starting point, though it also increases noise and render time (typically less than geometry methods).

[seandunderdale]

The directional feature also focuses light into a more intense result doesn't it? I'm not sure of the mechanics behind it, but I dont find it achieves the same result as opening a Kino Flo or using barn doors on a fresnel spotlight. The times Ive been in a studio with an automotive photographer, it was interesting to watch how much they controlled the light on the walls or the hard light on the car using these tools on physical / real world lights.

Using geo can work, but I'm not surprised if it does slow the render down. Also, when using a dense CAD asset, its nice to avoid moving geo too much since its more taxing on RT refresh than changing light settings which are pretty much realtime, even with a heavy asset.

[Joelaff]

Directional makes the rays more parallel. It’s like a grid spot, but without any losses. So more directional gets brighter, yes.

Geometry or HDRI lighting are going to be the most controllable. Though not the fastest.