Beta 4: interior try out

[kwistenbiebel1]

Hi all,

This is a try out of a kitchen space using the render option settings that Corey proposed in the 'Basic Interior Scene Settings Tutorial' (irradiance map + light cache).
I don't dare change anything of those settings because I really don't understand all those parameters (accidentally loose the sky, etc...). it would be nice if all the render options were explained in a tutorial, especially sky options and material settings like specular/gloss control.

I also try to brighten up the right side of the image using those chrome spotlights but even with multiplier set to 2000 the 'emitting layer' i assigned to the light surfaces don't cast any light on objects. Am I doing something wrong?

Another thing: How can i control the sun light not burning some areas, while still having a bright interior?

Any other suggestions about improving the image are welcome?



regards,
kwistenbiebel

[kwistenbiebel1]

Re: Beta 4: interior try out

...Another thing I struggle with is how to UV map a bump map.
The UV mapping of the SU texture is preserved by Vray and used in the diffuse slot.
The uv-mapping of the bump map however can't be done in Sketchup because the SU material slot is already taken by the diffuse texture.

I hope my question is clear

regards,
biebel

[kwistenbiebel1]

Re: Beta 4: interior try out

another try on an interior scene.
I am still not able to control sun strength.
Some parts of the image look overexposed while some parts are too dark.
Ayone an idea how to overcome this?

[joe_b]

Re: Beta 4: interior try out

...Another thing I struggle with is how to UV map a bump map.
The UV mapping of the SU texture is preserved by Vray and used in the diffuse slot.
The uv-mapping of the bump map however can't be done in Sketchup because the SU material slot is already taken by the diffuse texture.

I hope my question is clear

regards,
biebel

UV stuff is an issue with Sketchup - if you have a texture applied to a sketchup face/group then you can use Explicit Mapping Channels - because SketchUp will generate UVs for you if you've applied a texture to a face.

If you haven't applied a Sketchup texture to a face/group then you will have to use one of the UV generators that we provide. The only one's we provide at this time are planar/object mapping generators. I'd like to add a surface UV generator as well, because I think that is all that Sketchup really uses anyway.

[joe_b]

Re: Beta 4: interior try out

another try on an interior scene.
I am still not able to control sun strength.
Some parts of the image look overexposed while some parts are too dark.
Ayone an idea how to overcome this?

You can get to the sun settings by going to the Environment section of our global settings. Click on the [M] button next to GI (by default we have the Sky used as the GI/Background environments). Then you can modify the intensity multiplier to adjust how bright the Sky is. Below is a breakdown of the Physical Sky's parameters as explained at http://www.spot3d.com (V-Ray Docs)

[*]Turbidity - this parameter determines the amount of dust in the air and affects the color of the sun and sky. Smaller values produce a clear and blue sky and sun as you get in the country, while larger values make them yellow and orange as, for example, in a big city.[*]Ozone - this parameter affects the color of the sun light. Available in the range between 0.0 and 1.0. Smaller values make the sunlight more yellow, larger values make it blue.[*]Intensity multiplier - this is an intensity multiplier for the VRaySun. Since the sun is very bright by default, you can use this parameter to reduce its effect.[*]Size multiplier - this parameter controls the visible size of the sun. This affects the appearance of the sun disc as seen by the camera and reflections, as well as the blurriness of the sun shadows.[*]Shadow subdivs - this controls the number of samples for the area shadow of the sun. More subdivs produce area shadows with better quality but render slower.[*]Shadow bias - moves the shadow toward or away from the shadow-casting object (or objects). If the bias value is too low, shadows can "leak" through places they shouldn't, produce moire patterns or making out-of-place dark areas on meshes. If bias is too high, shadows can "detach" from an object. If the bias value is too extreme in either direction, shadows might not be rendered at all.

[dalomar_cg]

Re: Beta 4: interior try out

A few pointers about working with vray sun/sky. The first being that the model of the sun that is used is very bright, and in reality the sun is very bright. So just keep that in mind when you are adjusting the multiplier. All of the test images on spot3d are @ .01 for the intensity value, so you may need to go lower than you'd think to get results.

Next point, using the physical sun works best when also using the physical camera. This will have a more natural look to your sun, and it should also act more predictibly. As far as setting up the physical camera, the only thing you will need to adjust is the shutterspeed and/or the aperture (you can change ISO if you want as well). Most other values you can just leave at their defaults. So with the camera enabled render a view of your scene (make it quick if you can). Depending on your scene, it may render too dark, too light, or just right. In the case of dark or light press the first little button on the bottom of the framebuffer and a window will popup with some crazy graphs. At the top of that is a little triange with 0.00 under it. This is your exposure control. Now press the second from the last button on the bottom that looks like a black circle. This enables you to see the effect of the exposure control. Now you can move the little black triangle back and forth till you get the right exposure. How much you have to adjust the exposure will tell you how much to change either the shutterspeed or aperture. Either faster shutterspeed or higher aperture will make your image darker. And either slower shutterspeed or lower aperature will make your image brighter. Adjust either one of those settings and rerender. This time make sure you unclick the black circle or it will apply the exposure correction that you had on the previous image. It make take a test or two, but once your there the physical camera has the capability to do much better renderings.

Last, but not least is to use Reinhard color mapping, and decrease the burn value from 1 to .8 this can also help with controlling the burned values

[kwistenbiebel1]

Re: Beta 4: interior try out

Thank you Joe and Dalomar.
That information is very usefull.

Thanks

[stinkie]

Re: Beta 4: interior try out

" At the top of that is a little triange with 0.00 under it. This is your exposure control. Now press the second from the last button on the bottom that looks like a black circle. This enables you to see the effect of the exposure control. Now you can move the little black triangle back and forth till you get the right exposure. How much you have to adjust the exposure will tell you how much to change either the shutterspeed or aperture. Either faster shutterspeed or higher aperture will make your image darker. And either slower shutterspeed or lower aperature will make your image brighter. Adjust either one of those settings and rerender. This time make sure you unclick the black circle or it will apply the exposure correction that you had on the previous image. It make take a test or two, but once your there the physical camera has the capability to do much better renderings."

Why is rerendering important?

[kwistenbiebel1]

Re: Beta 4: interior try out

Ouch Stinkie, that's an old thread you're digging up. Beta huh? ;D

As an answer to your question about 'having to rerender':
I believe that setting 'exposure' on the fly while rendering doesn't give correct output because the new exposure setting hasn't been calculated in the pre-passes.

In order to get correct results for a changed exposure it needs to be set in advance, so the vray engine takes it in account even at pre-pass stage.
At least this is how I understand it works...

[stinkie]

Re: Beta 4: interior try out

Yeah, pretty old. I was going through the forum in the hope of understanding more about Vray. It's UI isn't quite like my beloved two slider app's one.

Thanks for the info!

[kwistenbiebel1]

Re: Beta 4: interior try out

He he, I like that '2 slider ' app a lot myself

Vray can be difficult to learn in the beginning, but once you get the hang of it, it can produce really good output. It makes you want to forget about unbiased render engines, especially for interior scenes as render times are way better.

As I understand, Asgvis team will provide an updated VfSU (I believe it's set for october), so good chance we will see some improvement on the workflow part.

Cheers,
Biebel

[stinkie]

Re: Beta 4: interior try out

I'll be looking forward to that. As I am to P. V2. In the end, I guess I'll have a full 'toolbox' and an empty wallet.