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Whiter Ceiling


JSiegel

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Hi All, How do you get a ceiling to appear as a white ceiling? In the attached screenshot the rendering is Custom Renderworks. Lighting=Use Shadows. Shadow Mapped Shadows= High,High.

The ceiling is a texture, BM White Cloud color w/ phong reflectivity. I have (7) spot lights & the (4) Undercabinet flourescents. Any thoughts are appreciated. TY J

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The problem traditionally has been that any white 3-D object

often renders as grey, and appears excessively dark (I think it

actually renders accurately, it's only a perception issue I believe).

Adding and adjusting lights is too time-consuming and often yields

unexpected results (and increased rendering times). There's no texture

combination (meaning with reflectivity, etc.), to my knowledge, that

can lighten the appearance of such a 3-D object in a controlled fashion

other than Constant, and that one is uniformly white with little

ability to accept subtle shadows. There is, however, a way to do this.

For a ceiling: make an extruded 3-D object with a white fill. Duplicate

it in place, and nudge the duplicate down by a couple of pixels, just

enough to see in close-up wireframe. Create a Constant texture, and

give it about 80% transparency. Apply this texture to the nudged

duplicate 3-D object. The transparency of the Constant texture will

allow the underlying object to be seen as a solid, but the 20% texture

visibility will create a lighter appearance, while allowing subtle

shade and shadow effects upon its surface.

An example of such a texture can be seen here:

http://www.danjansenson.com/whiteceiling/

Note that the ceiling above and the wall to the right both have white

fills. It's only the ceiling duplicate that received the 80%

transparent Constant shader. The white-ness of the ceiling can be

controlled by altering the amount of transparency in the texture.

Dan Jansenson

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Hallo,

You get a much more realistic look of your Ceiling if you enable Final Gather.

For the final renderings I also enable "Use Ray tracing" and set the refractions to 4 or 8.

If you keep the Final Gather accuracy low (like 30% to 50%), you still have acceptable render times (depending on your patience..).

The light sources for the attached renderings are 6 Point lights (like bulbs) 0.3m (1ft) below the ceiling.

The ceiling and the walls have the Stucco_medium_White texture, and receive a lot of yellow light, because the reflectivity of the Floor (a carpet of nature colored sisal) is set too high, but you can see the effect of the Final Gather for the ceiling.

What Ray and Jonathan write is correct, because if you have the lights close to the ceiling, the ceiling gets most of its ilumination from the reflections caused by the walls, the floor and the furniture, therefore it is really darker (but never dark grey!), but we adapt that and "see" it as bright as the walls.

That is what Final Gather adds to the Renderings.

Edited by Horst M.
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I gave Horst's suggestion a shot and 3.5 hours later I am still looking at the color wheel...so apparently I am not that patient. I have tried to Escape the Rendering & Force Quit Vectorworks each to no avail, so I am shutting down my computer. I will try Dan's suggestion & post the result tomorrow. Thanks for you comments. J

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Hi Jeremy.

I feel guilty.

3.5 hours is far more patience than I have.

The renderings above, with Final gather at 30% and Ray Tracing at 8 refrations took about 3-5 minutes to render.

Final Quality Renderworks takes about 1 minute.

both on my Mackbook Pro.

I think Rebnderworks crasehd in your case.

I will try later on if the extreme slowness could be caused by Line lights, which seem to be part of your Scene.

Edited by Horst M.
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I ran some tests, removed the line lights and FQRW & Custom RW each took @ 2.5-3 mins. As soon as I started with the Final Gather & Ray Tracing, I get the color wheel time suck & bailed after 20 mins. BTW I am unable to either "Esc" or "Force Quit" out of these renderings.

Dan, when you refer to "Constant Texture" and adjusting transparency am I correct in assuming that you mean adjust the "Opacity" of the new texture in Tools>Organization>Class Palette. Let me know as I don't see where else I would make these adjustments.

I have attached a CRW screen shot, ceiling is solid fill white, no texture.

TY J

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I have noticed that in general to get the ceiling (other white/light objects) to look white 'enough' when using phong/matte etc reflectivity, you need to, a) give all textures an ambience of about 60% ie decrease their default ambience, and the ceiling 100% then go to View>Lighting>Set Lighting options and fiddle(increase) with the brightness until the whole render looks good.

So basically you are decreasing ambience in all other textures and increasing the brightness of the scene........

Edited by Vincent C
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The thing that has not been mentioned yet in this thread is that one way to speed up test renders is to turn down the DPI of your layers. If you go down to 72 dpi it will take about 1/16 the time as 300 dpi.

That way you can do the tests fast to get the lighting/textures right and them turn up the resolution for final output.

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This may be helpful for others,

1. Ceiling: is a Texture BM Decorator White- Plain Color, no reflectivity, transparency or bump.

2. Lighting Options: Ambient on at 45% Brightness, Color Temp 3400K

3. Lights: (8) point lights in the recessed cans 850 Lumens, 25% dimmer, (6) point lights 1'-0" below ceiling 1150 Lumens, 2800K, 35% dimmer, smooth distance fall off, (1) spotlight outside window 50% brightness

I would still like to brighten it a bit. Any thoughts?

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Hi J,

I still don't think, that the vertical jagged lines are are caused by the dpi setting,

because the two clours are rendered with very precise edges, and they are bigger than 1 Pixel.

Could you post a File with just one Cabinett door inside. I'm almost shure, there must be something with the geometry or RW that causes this effect.

To finalise your Image, brighten the whole thing up, or just certain Areas, I would like to suggest using Photoshop or Gimp.

Less waiting and more possibities, and you could also get rid of those Vertical dashed Lines as well. :-)

I use Photoshop Elements, and find it not too complicated, and for colour-, brightnesscorrection, and some makeup its fine, and also cheap enough.

Edited by Horst M.
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Hi,

I did some Renderings, and can't reproduce the dashed effect, but I opened your Cabinet Symbol, and found that you constructed your Cabinet with the Multiple Extrude Tool (which I don't like very much, because I found that it created Objects that don't snap very well)

and that the basic 2d Polygons for these Extrudes are drawn with with a dashed Line Style!

I'm very curious, what happens with your rendering, when you Edit the 2d polygons of the Multiple Extrudes and set the lines Style to Solid....

Edited by Horst M.
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Ray, the counter is still an open question, it will be supported either with steel angles, concealed in corbel/bracket or per my prior "Lathe" inquiry, I may support the ends on a column/leg.

Horst, the Cabinet symbol is simply the ungrouped stock VW cabinets & I did not notice that they were "dashed" lines when revising them. Great find, apparently there will be (1) more final rendering. Many thanks, J

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