Non rectangular light meter?

[jamie_norrisgreen]

Is it in theory possible to convert a non rectangular planar surface into a light meter perhaps with a well written script?

[jamie_norrisgreen]

Can no one advise? This would be a game changer for me as a lighting designer.

[vlado]

Internally the V-Ray light meter just performs texture baking with the Illuminance/luminance render elements so in theory it is possible to use a non-rectangular shape. If we added the ability to select a custom geometry instead of the built-in plane, would that be enough?

Best regards,
Vlado

[jamie_norrisgreen]

Hi Vlado,

Thank you for you reply. I really appreciate it. That's great news its possible, I would love to be able to use V-ray for lighting calculations & visualisation at the same time. I'm sure there are lots of other lighting designers that would be interested in this workflow. Especially since lighting designs are often working with Revit models. Linking in the Revit model to 3ds max and visualising the lighting with v-ray photometric lights works very well, the LightMix element is super useful, to be able to also extract light levels in the same way something like 'Dialux' does but get great images out too, all while co-ordinating with an architects Revit model would be amazing.

A few things that I imagine would be very easy to add in to the light meter that would make them more useful to lighting designers would be a few other metrics from the light meter:

Eav [lx] (average of all the points on the light meter)
Emin [lx] (lowest point on the light meter)
Emax [lx] (highest point on the light meter)
u0 (Uniformity - lowest point divided by average of all points on the light meter)
Emin / Emax (lowest point on the light meter divided by highest point on the light meter)

Lastly If there was a way to output these specific metrics (instead of all the data for each point) for all light meters in the scene, into a table it would then be viable to use V-ray for lighting calculations.

If there is anyway I can be helpful on this please let me know. Id be happy to test anything out or input form a professional lighting design perspective.

Kind Regards,

Jamie

[jamie_norrisgreen]

Hi vlado, I realised I didn't directly answer your question, yes it would be enough if you add the ability to select a custom geometry instead of the built-in plane, it would also be great if you could add the following data to come out of the light meter:

Eav [lx] (average of all the points on the light meter)
Emin [lx] (lowest point on the light meter)
Emax [lx] (highest point on the light meter)
u0 (Uniformity - lowest point divided by average of all points on the light meter)
Emin / Emax (lowest point on the light meter divided by highest point on the light meter)

Lastly a way to output these specific metrics (instead of all the data for each point) for all light meters in the scene.

Is there much chance of this being implemented?

Kind Regards,

Jamie

[jamie_norrisgreen]

Being able to choose custom geometry instead of the built-in plane, would be great. Please implement this. A problem I have with the light meter at the moment is, it seems to take into account all lights int he scene whether theyre hidden, frozen, non renderebale or not. The only thing I can do is delete the lights I dont want the meter to see. Is there anyway around this?

[hermit.crab]

A problem I have with the light meter at the moment is, it seems to take into account all lights int he scene whether theyre hidden, frozen, non renderebale or not. The only thing I can do is delete the lights I dont want the meter to see. Is there anyway around this?

Lights work even when hidden/frozen, yes. However, if you make them non-renderable through their object properties, they shouldn't affect the VRayLightMeter. Another way is to turn them off instead of deleting is via their "On" switch.

[jamie_norrisgreen]

Ah ok, thanks for the info. I work with layers - layer manager for different lighting scenes (a lot of lights). Making them non renderable in the layer manager didnt stop them effecting the light meter. Its a little bit time consuming having to go into all the different lights in the scenes and make them on/off. I guess selecting all on the layer and making non renderable via object properties would be aa reasonable work around. It would be better if the light meter respected hidden lights and the 'render hidden lights' in global switches.

[jamie_norrisgreen]

Is there any news on the ability to select custom geometry as a light meter? Is it possible it will be in the next version?

[hermit.crab]

Is there any news on the ability to select custom geometry as a light meter? Is it possible it will be in the next version?

No news, I'm afraid. I think it would be best to add the idea to the Portal - this way, based on users' votes, its implementation can be prioritized. Add a link to this thread, too.