Specular causing slowdown

[re:FORM]

Amazingly, without colour-mapping, and the light multipler up to 1.0, the rendertime for that small square region rockets up to 12:26 minutes! And, that's with reflection subdivs at 1,
rQmc min max = 1/100
use Qmc sampler threshold = on
rQMC Adaptive = 1.0
Noise threshold = 0.01
min samples = 2
Global subdivs mult = 1.0
path sampler = default

I'm using Irr/Qmc GI, with QMC gi subdivs=8 bounces=3
IR map on the low preset.

Here's how the two versions look.

[vlado]

You can actually try this: add an Unclamped color render element and turn off its color mapping option, while keeping clamp colors and sub-pixel mapping on for the actual render. Now V-Ray will calculate the actual render relatively fast, and you will also get the unclamped HDR image with the nice hilights too.

Other than that, it is really an eiter/or situation.

Best regards,
Vlado