Vray camera shutter speed affecting render time

[Bowen Studios]

Our office has recently started using the Vray Physical Camera & have noticed that our interior scenes are rendering a lot slower (2-3 times slower) when using exposure. I have attached 2 print screens showing the difference.

We are using Max Design 2012
64bit Windows 7
V-Ray 2.20.03

The only two items in the scene are a physical camera & the background image.
I have also turned off GI
The only change between renders is the shutter speed (render times are also effected by changing the f-number & film speed (ISO))

Is there something we need to adjust to speed up the renderings when exposing for interior scenes?

Thanks,
Bowen Studios Team.

[simmsimaging]

Vlado or someone can clarify for sure, but overexposed shots - like your first example - will generally render a lot slower. I think it is mainly due to anti-aliasing requirements for excessive brightness variations between pixels. You can probably verify by turning exposure control right off and comparing the render time to your overexposed version - my guess is that they will be much the same, and both will be longer than a correctly exposed scene where the brightness ranges are much smaller in general.

/b

[flat]

see this thread
http://www.chaosgroup.com/forums/vbu...read.php?67419

[simmsimaging]

Thanks for the link - I missed that thread. Looks *hugely* useful. Still - decent exposure control is still an important part of this I think.

b

[Bowen Studios]

Thank you, that is helpful.

So, it looks like if we set the exposure for a lot of contrast, it will just take longer to render. I've tried checking "Don't effect colors", but that doesn't adjust for exposure, only gamma correction. I will test the different color mapping settings a little more.

Thanks again.

Jacob
Bowen Studios