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Renditioner compatible with sketchup 2014 available in the general discussion thread - SKETCHUP 2014.

Lights that don't work right
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* January 28, 2011, 02:36:33 PM
I've been grappling with the learning curve on this program for a while now and I've reached a point where I basically get it. I understand how things work pretty much. What bothers me and is always frustrating is that lights don't really work the way they do in the real world. For example, I created a small 10' by 10' room with an 8' ceiling, no windows. I began placing IDX lights in the space to see how they worked. I put every light on a different layer so I could turn them on and off at will. I then proceeded to preview render the space with different lights. The walls, ceiling and floor are an off white color. The results are not what I would expect if the lights are, in fact, supposed to act like their IDX description. I would expect, for example, that placing a couple of 100 watt incandescent wall sconces on one wall, the space would be pretty bright. It is lit, but there's a lot of darkness in the corners. If I place one fluorescent ceiling fixture, it lights the space more than if I put three. I've read about some issues that relate to this, and I have the latest version of Renditioner with the brightness and contrast controls. I can light a room well with these tools. What I want to do is light it realistically so I can show a client the difference, say, from having under cabinet lighting and not having it. I understand that this stuff is complicated, and I really appreciate what this program can do for the money. I'm not complaining. What would be very helpful is to have a comprehensive tutorial that would address different scenarios and go through the lighting strategies to get a realistic look. I don't think that's out there yet.

I'm attaching two renders that I did for a client to demonstrate this under cabinet lighting thing. It's not terrible, but it took a lot of work, and it was a little haphazard. And by the way, why does a black dishwasher face appear red?

[attachment deleted by admin]

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* January 29, 2011, 01:22:22 PM
#1
No render app can duplicate the dynamics of a person viewing a scene. Our head and eyes moves around in order to get an impression of a scene, and the render app is like a camera. The current version of Idx has limitations with contrast ranges on interior scenes with artificial lighting, and your best bet is to quickly render (for detail) then post process (adjust lighting and contrasts dynamic range). IMO its a mistake to present any render as a accurate depiction of light to your client. Only asking for trouble latter.

Don't know about the "red" face. Are you sure its not a duplicate face in the same plane of the SU model? I have inadvertently hidden images that Idx renders, but not had your kind of problem.

Is that a open space on the left side of the scene?, if so, light the walls in the back and try to take the space out of the shadows.
« Last Edit: January 29, 2011, 01:28:43 PM by honoluludesktop »

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February 12, 2011, 08:43:30 AM
#2
Something that will help with dark renders is to give the back wall a different value, try the glow setting with the slide a fair bit to the left.  This will give the 'impression' of a lit wall even if we cannot accurately portrait lights in a like for like sense.  I believe a search would have shown a demonstration of this, from memory a kiosk of some kind.  Let's see where you get with this please, always nice to see how other users get on with their renders.

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Chillblast PC
i-7 3.07ghz 64 bits system.
nvidia GeForce GTX 460 1gb Graphics Card.
16Gb Ram.
Win 7 64 bit.
Renditioner Pro v3 (2.3.81851-2.4.81818-8.3.80994)


* February 14, 2011, 02:35:02 AM
#3
If you put more lights in a room the render will be darker because of overexposure. The IDX camera works a bit like a digital camera and tries to even the lights and shadows out, same with colors. If you only have a few colors in a scene the colors look very bright and you need to adjust the saturation of that material or put more objects in a scene with different colors.
To get best results for interior renders is to set lighting settings to cloudy and don't make the interior lights to bright.
You could also change the material settings of a roof to reflect more light.

I woulds say, keep playing and the more you play the more you learn to adjust the settings to a way that's good enough for your renders.
And yes also post processing to get the lighting results you want.

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Tony van Loon
Civil Engineer & 3d Artist


* February 14, 2011, 07:48:26 AM
#4
Thanks all for your comments. I'll keep playing with the program until I get a sense of what works best. Your ideas are very helpful. By the way, the two renders I uploaded I showed to the client. I warned that the lighting would not be exactly like the render, but perhaps the difference with and without the under cabinet lighting might help them decide. They went for the under-cabinet lighting because of the render, and I think they'll be pleased with what they end up with in the real world.

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* February 15, 2011, 06:09:05 AM
#5
Whilst Renditioner is an excellent renderer for use in SketchUp, I would suggest that it isn't lighting design software.

You might want to have a look at ReluxPro which is a free lighting design software and will allow you to produce accurate lighting level diagrams for your client, although they may not look as attractive.


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