light and material study

[Fletch]

Jerome,
Lots of great free studio HDR images here.
Alvydas at Kerkythea's forum wrote here about which are his favorite:

[JeZ]

Hi Fletch,
I was exactly in that direction.

I am rather satisfied by these studio skies alone, now that I understand better how to tonemap (thanks to you! )

Then, I think you answered a question That I did not yet thought of... my studio background is not right.

Then again, I have a hard time visualizing the hdri: how it is positioned, what it really looks like when wrapped as a sky, etc. If you have any tricks about that it would be great


Heres some test renders with hdri sky only.

I think think the painted glass cabinet looks great.

I think all of these are lighted by studio24

Cheers

Jerome

[Fletch]

... I have a hard time visualizing the hdri: how it is positioned, what it really looks like when wrapped as a sky, etc....

hide all objects, and render low resolution (600x800 or less) with Easy08 just one pass to preview the sky - will render quite quickly.
then use the "Sky Rotation Angle" slider in the Sun&Sky Tab of the Lighting Dialog to change the direction the HDR image is pointed... re-render preview... adjust.

It's so simple, it's a little scary... it's such a pain or impossible in so many render programs I've tried.

[JeZ]

hum... not sure I understand what I am supposed to see

I know about the sky rotation, though I am not sure if it is relative to the model's axis or the camera. I think it is wrapping the model CW from the red axis (the third quarter on the green), right?

(hopefully it is not written in the manual)

Jerome

[Fletch]

well, I thought you wanted to be able to see the sky... you can see it now. If you change the Field of View (hold shift key while zooming out with the magnifying glass in SketchUp) you will find you can see more of the sky.

or - you may want to put a mirror ball in the image so you can see what it's reflecting?

[JeZ]

Thanks Fletch.

I think I will be able to work with the hdri files.

I updated the lighting, maybe changed the backdrop mat and prefer a smaller backdrop.

or

I am currently working on some better wood settings

Cheers.

Jerome

PS Well, I am looking at that new render and it is definitely too saturated or "contrasty"...

[Fletch]

I think it is looking beautiful.

balancing contrast is a matter of balancing the gamma and exposure values... decreasing the gamma number will icrease contrast and saturation. increasing exposure will lighten the entire image, but the lighter parts of the image seem to be effected more greatly by this than the dark areas.

do not be afraid to use only a decimal point change... so if you have gamma at .9, and you need just a little extra light in the scene, try .95, .93, .97 I've seen some models where a few decimal points makes a real difference in the outcome.

[JeZ]

Fletch, that is a great tip. I'll try to not forget it.

I have been work on 2 new studies.

The first one is a collection of material that I intended to keep as a palette. The woods are supposed to look like they are varnished with my standard finish (a flatish satin coating - 20deg glossiness). I think it is good enough. I tried hard to find a way to get some more soft reflections with the bump visible in it (i guess fresnel effect? The grain should be rather visible in such reflections... ). I guess the quality of my lighting is still my biggest problem... If anyone is wondering these samples are more or less 8,5in x 22in (so approx. 2 A4 long)

The second study is an old model that is inspired by a very nice Cattelan piece. The materials are oak (the far right one in the samples render) and a white polished lacquer that definitely dont work. I dont understand how to do a reflective paint mat


All C&C would be very much appreciated.

Cheers.

Jerome

[Fletch]

great materials shot there, I thought it was a photo for a while...

Try to make sure your paint color is not 100% pure color anywhere. White and Blacks are especially important for following this rule.

If a pure 100% white has light shining on it, what color should it become?
Same for black - if a shadow falls on a 100% black surface... what color should it become?

Very few things in life are that black or white... I actually usually go to 85% saturation and brightness for any colors. Remember that the "Color" channel is the "Diffuse Color" of the material. This means "the color of the surface as seen in indirect light" so... on a perfectly flat cloudy day with the flattest indirect light possible.

I use the Noise map provided in the red carpet section hires materials in the bump slot for the paint material.
I usually apply "paint satin" template first, then copy the RGB number that is listed in the color slot.
Then unlink the color from the SU model.
Then paste the color number you just copied back into the color slot.
Then link the bump to the scene, and find the noise map.
It will now load it into the SU view mapping it onto the surface.
Inside the SKETCHUP material editor, change the scale of the noise map large enough to start seeing individual pixels of the texture in the viewport.

Try a test render, and adjust bump strength and scale of texture until happy.

[JeZ]

Hey Fletch,
My diffuse color is ok, it should not be the problem.

To me, it looks like a reflection problem. I dont know which template to apply to get crisper reflections.

What settings would use for high gloss piano finish or solid acrylic panels, like http://www.parapan.co.uk/ ?

Cheers.

Jerome