Dense about Vray lights

[PGolay]

Hi All- apparently I am not getting it about lights in Vray- in particular lights that have decay (Point, spots) seem never to generate enough light to overcome the decay (using the defaults so far)- I have maxed the light output (10000 ) on a spotlight and there is very little to show for it, all the light seems to be coming from my rectanglular light which I'd hoped to use as a general fill at .5 or so intensity. The spot shows in refelections but not much action in terms of light thrown.
I assuming default decay setting of 1.5 on the spot- presumably 2 is realistic, but that would be even less light getting to my objects. The scene is more or less accurate small room sized with the light source in the 'room'.

So, I'm sure it is simple enough but I have not found it yet- thanks for any pointers...

-Pascal

[flipside]

Dense about Vray lights

Altering the decay will give you more light, but I would also like to know what this decay actually means. These lights behave very strange. What decay settings corresponds to inverse square decay?

[PGolay]

Dense about Vray lights

Altering the decay will give you more light, but I would also like to know what this decay actually means. These lights behave very strange. What decay settings corresponds to inverse square decay?

I'd guess 2 is the same as square. But in real units as one models in Rhino, there seems to be no way to set a light in a 'realistic' position and still get enough light into the scene.

-Pascal

[corey]

Dense about Vray lights

A decay of 2 is Inverse Square. What you folks maybe be over looking here is the Hardness.

Here is a scene file.

Here are images.
Hardness 1.0
Hardness 0.5
Hardness 0.0

My floor plate is 8' x 8' and the spot light is located about 8' from the floor plane.

Hope this helps.

Best regards,

Corey

[PGolay]

Dense about Vray lights

A decay of 2 is Inverse Square. What you folks maybe be over looking here is the Hardness.

Here is a scene file.

Here are images.
Hardness 1.0
Hardness 0.5
Hardness 0.0

My floor plate is 8' x 8' and the spot light is located about 8' from the floor plane.

Hope this helps.

Best regards,

Corey

Hi Corey- thanks- that is useful but there is still the problem of scale and units- if I change your model to milimeters and scale it so that the distances are the same (light ~2400 mm from the ground) there is not enough oomph available for light to reach the boxes even at 10000 using inverse square decay.

-Pascal

[corey]

Dense about Vray lights

Pascal,

We will test and look into this as soon as we can.

Best regards,

Corey