Lighting Analysis Image Overlay

[zoranm]

Hi,

I was looking into this feature and did some test in preparation for an upcoming job.

Couple of questions and observations ( since I couldn't find any help files). So, I'd appreciate if someone could clarify for me:

It's nicely done: it can separate direct and indirect light contribution. Logarithmic scaling is nice although it could probably go into Display Options.
It looks to me that metering is not influenced by the color mapping, exposure control or texturing. It'd be nice if someone from ChaosGroup could explain how it actually works? I have to justify this tool to my architects.

1.Effects\Illumination Analysis Image Overlay\Parameters panel: Show Numbers From Light Metering Helper Objects doesn't work for me. Even if my Light Meter helper object is active nothing happens. What am I missing?

2.There is quite a bit of discrepancy between Light Meter and Lighting Analysis Image Overlay results (see image). Which one is physically more correct? Where is this diference coming from?

3.How to render Light Meter readings onto images (this is probably connected with question 1)?

4. What are Orientation lines showing? Direction of the biggest lighting contribution?

5.Is there a way to control text size in Lighting Analysis Image Overlay. On large prints it's barely visible.


Test Images:




Basic render: cam exposure on, color mapping=linear 1,1,1 grey materials Vray Sun+Sky



Lighting Analysis Image Overlay. Note slight darkening of image




Lighting Analysis Image Overlay combined with Pseudo Color Exposure




Test with textures



Light Meter screen capture. Note huge discrepancy compared to Lighting Analysis Image Overlay effect

Thanks and regards

Zoran

[zoranm]

Could anyone from Chaos Group, please, answer my questions?
Particlularly the one about discrepancy between effect and light meter.
My deadline is approaching.

Regards

Zoran

[rajdarge]

can I ask a dumb question ?
What is this and how do you get it going. I tried "Effects\Illumination Analysis Image Overlay\Parameters panel:"
and there was no such beastie in my 3ds Max. Is it specific for Max Design?
At least it shows me how you might use a light meter with more than one point of sampling (being a photographer I was struggling to understand its functionality).

As far as the text display goes - I think I can answer that. It uses a default screen rendering font that is the same across all max Viewport text display functionalities. Its the same one that displays the viewport FPS etc and the Viewport name. It doesnt even do perspective that font. Thats my guess.

Why the discrepancy - who knows? I expect the light meter will get a great deal of re-writing with the next release (or so I hope).

Raj

[glorybound]

Yes. It is a 3ds MAX Design thing.

[zoranm]

can I ask a dumb question ?
What is this and how do you get it going. I tried "Effects\Illumination Analysis Image Overlay\Parameters panel:"
and there was no such beastie in my 3ds Max. Is it specific for Max Design?

I belive it is. I'm on Max Design

At least it shows me how you might use a light meter with more than one point of sampling (being a photographer I was struggling to understand its functionality).

Yes, it's good in that respect. Only restriction is that you can use rectangular shape.

As far as the text display goes - I think I can answer that. It uses a default screen rendering font that is the same across all max Viewport text display functionalities. Its the same one that displays the viewport FPS etc and the Viewport name. It doesnt even do perspective that font. Thats my guess.

You're probably right.

Why the discrepancy - who knows? I expect the light meter will get a great deal of re-writing with the next release (or so I hope).

Raj

I hope so. It'll be a valuable tool and a source of additional income for us who do architectural visualisation and with some improvements it could become a standard procedure in analysing lighting conditions before going to do marketing shots.

regards
Zoran