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CHRiTTeR
11-03-2005, 05:54 AM
Do you guys have a good reference site to find the correct intensity to simulate light?

Right now I'm testing a little with photometric lights in max. Just some simple stuff...


For example, right now I'm trying to recrate the lighting done by a common 40watt lightbulb.
I know the colortemp. is about 3500 for this kinda light but...

a) What kind of intensity should I use? (lm, cd, lx)
b) How high should the intensity aprox. be?



Thanks!
PPGINGRAS
11-03-2005, 04:37 PM
I think it all depens on the size of your scene.

A huge scene scaling will demand higher Light Intensity since the distance is different from a smaller scene. Im talking Units.

I dont know about any Charts for light intensity translated into RGB or HSV values. I would go the trials and errors way.

Maxwell Render has an exact chart for light temperatures. But i doubt you wanna use that renderer since its totally production inneffective.


My 2 cents...
TiskO
11-04-2005, 05:37 AM
check out www.erco.com
it has a heap of free ies files. Also, make sure that you are modelling you scene to scale, as ies lights are built around real-world physics.
PPGINGRAS
11-07-2005, 05:05 PM
http://www.graphics.com/modules.php?name=Sections&op=viewarticle&artid=151

http://www.graphicsnews.com/modules.php?name=Sections&op=viewarticle&artid=153

http://www.graphics.com/modules.php?name=Sections&op=viewarticle&artid=157
CHRiTTeR
11-09-2005, 05:04 AM
PPGINGRAS:
Thanks for those links! They look like an intresting and educational read, I'll surely check them out later!


TiskO:
Nice! I've been looking for some good .IES files for quite some time now. But (theres always a but) how do I know what ies contains data from a lightbulb, TL or halogen? The filenames do mention the Watts but not the type of lightsource?

Also, how to know if I should load them into an omni, spot, direct or area light?




Still dont know hom much intensity an average 40watt lightbulb is (using inverse square falloff and correct scaling) ... :D
cpnichols
11-09-2005, 03:17 PM
TiskO:
Nice! I've been looking for some good .IES files for quite some time now.

You may want to check Lithonia too:

http://www.lithonia.com/Library/IESFiles/Default.asp?Path=/Lithonia_Lighting
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