Improvement Needed

[BillyRaygun]

Dear Forum,

I'm looking for suggestions on how to improve this rendering.

1) The back wall with the logo is supposed to be stretched fabric, white.
2) The inside and outside banding is supposed to be matte aluminum
3) Flooring is supposed to be carpet
4) River rock (tiled) is inside the wood frame
5) The white banding on the front is supposed to be back-lit.

In my opinion, I should have more color separation between the aluminum and white fabric. I have a light in the roof but it doesn't seem to illuminate the interior very well; is this the photo-realism of Vray? Simple structure, but seems flat.

I would love some direction as to improve on this. Been rendering with Vray for a while now and seem like I can't close to anything I've seen here. Of course, my industry is time sensitive so I don't always have a lot of time. But still, I should be able to make better renderings than this.

[Micha_cg]

Re: Improvement Needed

For photorealism it's good to play with light colors. I would use warm colors for the spots and a cold light from the environment, like from a big open door in the near of the booth. Or you simulate an opening in the ceiling with cold day light. Or use a HDRI at low intensity as general lighting (for example from the starterkit).
I use for light colors (HSV) - warm hue 34 and cold hue 210, saturation between 60 .. 10.

You could play with IES lights instead simple spots. It's a little bit tricky to get the right intensity, but the IES light generator should help.

http://forum.asgvis.com/index.php?to...34809#msg34809

back-lit ... if you use a constant color only, than it must look unreal. Add a glow effect per postwork and use gradient textures instead constant colors. I simulate lights behind milk glass per gradient textures often.


Use light colors for metals - steel is warm and aluminium cold (blueish) most.

Use a bump map for the river stones. If you can't create per image software, use crazybump.

Use a good visible carpet texture, maybe with bump for structure or some unevenness.

Add some glossy effects at the big posters - anything is so perfect clean.

Don't place all plant like copy&paste - rotate and scale the plants, use a little bit different colors for some of them.

[jrharvey]

Re: Improvement Needed

The stone could use some displacement as well.

[dalomar_cg]

Re: Improvement Needed

The aluminum looks flat because the environment is flat. Have something there to reflect and it will look more interesting. It doesn't matter if that's an HDRI, or some billboards/objects that are placed just off camera directly in line with the reflections.

If the back wall is cloth, then it won't be just a diffuse material. It will be retrieving some of its color/illumination from the back side lighting as well. I'd suggest trying a V-Ray 2 Sided material and playing around with some lighting from the back side.

The plants need to be way more lively. At the moment the look sad and are detracting from the rest of the scene. No need to be over the top with them, but they need to be more than what they are.

The lighting to me seams a little flat. You'd probably want more focused lighting around the portraits themselves and it looks like you've got a little bit of that going on the one on the right. You've also got it started a little bit on the logo for the photographer, but it doesn't seam like there's enough contrast with it and it seams a bit too focused.

[BillyRaygun]

Re: Improvement Needed

Thanks for all the good advice. I'll work on that. One question that stands out the most in regards to Micha suggesting a gradient texture.

@Micha - The gradient, I assume you are applying this to an emissive material with an invisible rectangular light just below that for illumination? From your example it is hard to tell. The glow obviously post process, but I can't tell about the light on the walls. Seems that it would be a lot of work for just an emissive material and that you need to supplement that with a rectangular light.

Regards,
Bill

[BillyRaygun]

Re: Improvement Needed

@dalomar - Regarding the 2 Sided material. I've never figured out how this material works. Actually, the whole material system in Vray seems cumbersome. Anyway, is your idea to have some transparency on the back side? Not sure what you mean exactly by using a two sided material w/ lighting.

Regards,
Bill

[Micha_cg]

Re: Improvement Needed

@Micha - The gradient, I assume you are applying this to an emissive material with an invisible rectangular light just below that for illumination? From your example it is hard to tell. The glow obviously post process, but I can't tell about the light on the walls. Seems that it would be a lot of work for just an emissive material and that you need to supplement that with a rectangular light.

Yes, I mean a textured emitter material. Emitter material send light to the scene too. The invisible rect light is only needed if your emitter is quite small and with high intensity - than the additional invisible light helps to get a cleaner light sampling. But in your case, a "glowing" frame, the emitter material could be enough.
Some times, if I need a light effect and a visible gradient at the emitter, I have the problem that the emitter material is so bright, that it is burned out. Than I use a low intensity textured emitter + an invisible light too. (If I remember me right this was the case on my posted image).

[dalomar_cg]

Re: Improvement Needed

The two sided material actually isn't that complicated with how it works. It basically has a material on the front and material on the back, and determines the shading for both as it normally would. Then, using the blend color, it will blend the two together. In simple situations, it doesn't really do much, but when you have more light coming from the back than the front it simulates thin translucency very well. One of the other things that helps a lot is having different textures on both sides, so that when the back "shows through" is different than what's appearing on the front. Also, it helps to not have flat lighting come from the back either. There really is no need to have transparency on either the front or back material.

The material system is built around flexibility, and sometimes for simple things, it can seam cumbersome. Most people find the use of colors instead of numbers slightly odd, and the layered system seams misunderstood by most. The reality is that is very easy to make a lot of changes that in other softwares would require changing material types or doing much more complex materials. In the next full version we'll have some preset material types (such as a basic material and a car paint material) that will put a prettier face on making some simple adjustments, but regardless of how the interface looks, its still the layered material structure underneath

[jrharvey]

Re: Improvement Needed

I dont think the material editor is difficult at all. Sure, it could be easier BUT it is not nearly as complicated as alot of other renderers. Using one material for everything is a great idea IMO. I hate how some have all these different types that do different things. its dumb. If you want to change a property you may have to start over on a new type of material. Oh well, my little rant.

[BillyRaygun]

Re: Improvement Needed

Micha and Dalomar; Thank you for your patience with me while I take my Vray skills to the next level.

Then, using the blend color, it will blend the two together.

Is this just the "color" setting?

There really is no need to have transparency on either the front or back material.

Then how does the light shine through allowing the back side to been?

Also, it helps to not have flat lighting come from the back either.

Such as a rectangular light parallel to the back plane?

@Micha - thanks for the continued support. I'm testing your suggestions between naps.

[dalomar_cg]

Re: Improvement Needed

The blend color is just a gray scale value that dictates how much of the final result will be from the front and back materials. 0, or black, should lend a result that is essentially just the front material, and 1, or white, should lend a result that is just the back material.

The light doesn't really shine through at all. The *appearance* of light shining through comes from mixing the materials. This is much more of an effective trick when there's a distinct difference between the lighting of both sides.

I would set it up with more contrast than a big rectangular fill light. Try to make more focused than fill. You can use whatever light type you'd like, but if you choose to use a rectangular light, it will most likely end up smaller (thinner maybe) than normal.

[BillyRaygun]

Re: Improvement Needed

@Dalomar - 10/4 on the blend color. Back to my point about the material library; when you say "blend color" is look for "blend color" in the material parameters.

Perhaps I need to keep more up to speed on the forum terminology. But ideally, it would be great to have "blend color" listed as such in the materials dialog.

Same thing with DMC/QMC. In previous updates, its confusing when we talk about one, see another etc.

I'm not complaining, you guys rock, the forum rocks. I just think terminology is critical in getting past the learning curve.

Cheers!
Bill

[Micha_cg]

Re: Improvement Needed

In the next full version we'll have some preset material types (such as a basic material and a car paint material) that will put a prettier face on making some simple adjustments, but regardless of how the interface looks, its still the layered material structure underneath

There was a wish two years before that would be an easy solution. If I remember me right I got the idea from the Maxwell plugin:

I hope the development will faster in the future, only a little bit ... no, it's frustrating slow yet.

http://forum.asgvis.com/index.php?topic=279.150

[Hoop]

Re: Improvement Needed

Hi BillyRayGun,

Definitely use Photoshop to add a glow effect to your backlit areas as Micha mentioned, I do this all the time with my exhibits and it really helps the client to understand that it's lit and not just white. The gradients are also VERY helpful in doing any type of hanging pendant, cone, or cylindrical light in achieving a more realistic effect.

I've taken the base aluminum that comes with VRAY and added an HDRI in the "background" and "reflection" layers to help achieve a fake environment to make the aluminum pop more. That way it's just applied to the aluminum and not the whole image. Sometimes that's good and sometimes not, depending on the look you want. You could try that and see if it gets you what you want.

Also, I've found that with fabric it helps a lot to add a reflection layer and a slight reflection value to the material. It helps to carry the light across the fabric a bit.

If your doing a tension framed fabric structure, it helps to draw the underlying aluminum frame and give the fabric an ever-so-slight opacity so that the frame is barely visible and appears as thought it's "stretching" the fabric. Unless your specking something with a light blocker in it obviously.

Anyway, I hope some of this helps, it's just some stuff I've learned along the way. Your design looks great btw.

Hoop

[BillyRaygun]

Re: Improvement Needed

Hi BillyRayGun,

Definitely use Photoshop to add a glow effect to your backlit areas as Micha mentioned, I do this all the time with my exhibits and it really helps the client to understand that it's lit and not just white. The gradients are also VERY helpful in doing any type of hanging pendant, cone, or cylindrical light in achieving a more realistic effect.

10/4 on photoshop but maybe I'm missing something. Gradient. What gradient? Also, what filter in Photoshop are you all using to achieve the glow effect? I'm not seeing anything called "glow".

I've taken the base aluminum that comes with VRAY and added an HDRI in the "background" and "reflection" layers to help achieve a fake environment to make the aluminum pop more. That way it's just applied to the aluminum and not the whole image. Sometimes that's good and sometimes not, depending on the look you want. You could try that and see if it gets you what you want.

I have done this several times, although it adds considerably to render times. Currently, I'm trying Dalomar's suggestion to use a plane behind the camera with an image. It seems to be working ok. I need to try it on this environment.

Also, I've found that with fabric it helps a lot to add a reflection layer and a slight reflection value to the material. It helps to carry the light across the fabric a bit.

If your doing a tension framed fabric structure, it helps to draw the underlying aluminum frame and give the fabric an ever-so-slight opacity so that the frame is barely visible and appears as thought it's "stretching" the fabric. Unless your specking something with a light blocker in it obviously.

This is interesting.

Your design looks great btw.

Thanks!


[/quote]