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wtdedula
04-08-2009, 07:37 PM
Hello All;
I am playing around with a simple model that I created but I've been trying for three days and just can't understand why I can't reproduce the same lighting on the object as the original photograph. The inside of the tube is rather dark but I'm not sure why the tabs attached to the tube are light. See the blue areas I circled. The upper one is a real problem. The bottom ones aren't that much a problem because you can't see inside the tube in my view but they should technically be darker too (A similar color to the inside of the tube). I positioned a light where I thought it was in the room but I just can't seem to get a similar lighting.

I have a few books on Lighting in Lightwave and I also ordered a DVD tutorial which should come any day now but if anyone can give me some tips/suggestions on how to fix this problem and get me going, that would be awesome.

Oh I've also posted a screen shot showing a few of my views in case this will help someone diagnose the problem.

Thanks much.

Tim

accom
04-08-2009, 11:34 PM
I'd say that the inner dark areas are invisible (i.e. the polygons of the tube are single sided), so you don't see dark inner surface, but you see the dark background. Turn 'doublesided' on for the material property.

Seeing the lightning setup would also help, but I'd say that your ambient light could be quite high. Reduce ambient lightning and set up a couple of lights to your taste.

multipass
04-09-2009, 01:43 PM
do you have shadows turned on in the render globals

wtdedula
04-09-2009, 02:27 PM
Hello All;
Thanks for your very helpful suggestions. I am getting closer but I still havn't been able to reproduce my ligiting exactly. See attached to see what I have so far. I don't remember what the ambient lighting of my previous example was but I am pretty sure it was low.

However, for my latest example, ambient lighting is 5%. Shadows are turned off.

While the lighting on the tube is fine, I can't seem to reproduce the light/dark on a few of the tabs like the one front center and rear center. I think I can live with what I have now but I would still like to be able to understand and control lighting precisely.

Tim

multipass
04-09-2009, 05:51 PM
did you try turning shadows on?

toby
04-09-2009, 09:15 PM
To match the photo you need :
Shadows, preferably soft, like from a large area light.
Strongest light (key) coming from the right, not the left. Blue tint.
Weaker light (fill) coming from the left, yellow-orange tint
Object needs to be a dark beige on the inside instead of white, like the real one. That's why it's coming out too bright.
And a little radiosity, in addition to an hdr couldn't hurt :)

steamthunk
04-12-2009, 06:29 AM
Totally agree with Toby. If you need to match things exactly on the tabs you can always cheat and make them a separate surface and alter the diffuse setting.