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Martin Kay
08-26-2006, 01:59 PM
I'm experimenting with the EI lights to see what I can do with them. At the link below is a small test scene with a 3 light set up, 1 key, 1 fill and a backlight. The back light is causing a very hard edged shading phenomena in one part of the scene. Is this what you get, or can I do something about it? It happens with both spots and omni type lights.

http://www.martinkay-3d.com/EI_pages/3lights.html

Cheers Martin K

AzOne
08-26-2006, 03:16 PM
Does playing with the object texture diffuse or specular falloff cause any change?
Is there a dropoff setting for the lights?

Igors
08-26-2006, 05:04 PM
I'm experimenting with the EI lights to see what I can do with them. At the link below is a small test scene with a 3 light set up, 1 key, 1 fill and a backlight. The back light is causing a very hard edged shading phenomena in one part of the scene. Is this what you get, or can I do something about it? It happens with both spots and omni type lights.

http://www.martinkay-3d.com/EI_pages/3lights.html

It looks like UV seam

evant
08-26-2006, 10:12 PM
try changing the Factor setting in the light properties to .7

Martin Kay
08-27-2006, 08:17 AM
I did try adjusting settings, but its a lighting quirk.

Martin K

Igors
08-27-2006, 09:19 AM
Hi, MartinI did try adjusting settings, but its a lighting quirk.Never seen such lighting quirks:) . Minimize your prj, atchive and upload it, we'll try to help

BJMonkey
08-27-2006, 10:10 AM
Actually... EIAS lights have always done that... They don't seem to roll round the sides of teh shape no matter what.

The things you can do?
Add shadow transmission, (or SSS)
Or Add GI and you won't notice it so much.

This happens in the real world, but with infinate light bounces all the time, we don't notice it :)

Martin Kay
08-27-2006, 12:14 PM
Hi, MartinNever seen such lighting quirks:) . Minimize your prj, atchive and upload it, we'll try to help

Actually it happens also in c4d, after you add a shader. I tried it earlier to see...
I'll have a go at uploading the project later.
Cheers

Martin K

Martin Kay
08-27-2006, 12:37 PM
Hi, MartinNever seen such lighting quirks:) . Minimize your prj, atchive and upload it, we'll try to help

Here you go. Thanks for looking at it!

Martin K

Igors
08-27-2006, 01:29 PM
Here you go.Nope yet, there is no fact file in your archive :)

Martin Kay
08-27-2006, 02:09 PM
Nope yet, there is no fact file in your archive :)

I've downloaded it back to me twice and it's fine. Isn't technology wonderful....:scream:

Martin K

Using this forum is sometimes more complicated than form Z...

Igors
08-27-2006, 03:48 PM
I've downloaded it back to me twice and it's fine. Isn't technology wonderful....:scream:Still no FACT there:) Use "collect files" from File menu and then archive created folder, it's easy way to send prj. This time please don't worry, your problem is visible well just with a simple cylinder.

There is no any "criminal" and, yes, you'll have same/similar effect in any 3d app. Your back light intensity = 1.3 and it creates visually tight transition from light to dark. The simplest fix is to replace back light with 2 lights with intensities 0.65 that have a little different positions (radial sources) or directions (parallel sources)

Actually... EIAS lights have always done that... They don't seem to roll round the sides of teh shape no matter what.Light with soft shadow should illuminate some points even their normals are opposite to light direction. But it does not :sad:

Martin Kay
08-27-2006, 10:48 PM
Still no FACT there:) Use "collect files" from File menu and then archive created folder, it's easy way to send prj. This time please don't worry, your problem is visible well just with a simple cylinder.

There is no any "criminal" and, yes, you'll have same/similar effect in any 3d app. Your back light intensity = 1.3 and it creates visually tight transition from light to dark. The simplest fix is to replace back light with 2 lights with intensities 0.65 that have a little different positions (radial sources) or directions (parallel sources)

Light with soft shadow should illuminate some points even their normals are opposite to light direction. But it does not :sad:

Thanks Igors! I'll try that, and thanks for the info about 'collect files'

Martin K

Martin Kay
08-28-2006, 07:28 AM
Thanks Igors! I'll try that, and thanks for the info about 'collect files'

Martin K

Using two lights, radial or parallel, just gives two hard lines. Oh well have to live with it.

Martin K

Martin Kay
08-28-2006, 09:17 AM
Using two lights, radial or parallel, just gives two hard lines. Oh well have to live with it.

Martin K

I think the problem is the third light. I'm quite happy with what I'm getting with a two light setup. I suppose you'd normally only have one key and one major fill in most situations, but with interiors lighting can obviously get more complex.

Martin K

halfworld
08-28-2006, 09:32 AM
If not using GI, I find that it's generally better to use many low intensity fills...

This is where lightrig or illuminator domes come in.
Though that isn't to say you shouldn't use a higher intensity backlight or two as well if you want to.

A project I have on the go at the moment has around 20 fill lights in it (and about 280 other lights ;).
Ian

Martin Kay
08-28-2006, 11:04 AM
Strangely, I'm not getting the problem now.... I don't know why. Here's a three light setup with none of the hard edged perimeters showing. 1 key light and two fills.

http://www.martinkay-3d.com/EI_pages/3_lamp_test.html

Martin K

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