Glass

[IC]

Well I'm still playing!

[warprat]

well a heck of a player u are then. My god! that's good. But I dunno whats going on at the top of the glass and the bottom bit jagged, noisy??

 

well that was a gid' yin'

[IC]

Yeah I think it's too much bump.

 

Thanks.

[warprat]

well here's another go! quality 18, 3 bounces lighting quality at 0.8. the noise in the centre is sooooooooooo annoying. Got incidence angle gradient in reflections and trancparency. fast fresnel, all in glass. glass air no gradients. lit by a 4 point light setup all spotlights. how do you guys set your gradients? what are musts for getting good looking glass??

 

sorrry, something funny just happend. My post repeated it's self 5 / 6 times so I just dleted them all and edited this one should be ok now.

[IC]

Have you got anything for the glass to reflect in the environment channel?

Better still, use imageworld in the background tab and turn on backdrop radiosity in FPrime.

If you're using gradients, there's no need for fast fresnel as that's what you're creating with the (incidence angle) gradient. If you imagine the gradient bar is a diagram of your angle of view, looking at the glass directly would be at the bottom and looking at the disappearing curve of the glass is the top, so adjust the sliders accordingly. (Was that gibberish?)

[warprat]

ok that helps. thanks. I'll give it a go. I never could figure out what the bar stood for as in where the reflection would stop and start. hehe.

So u use alot of backdrop radiosity, do you ? I have just been putting in skydome's with luminosity set high.

thank you again.

[bavanor]

Coming from the photographic world, has anyone tried to setup a redner like a photographer would to do a product shot. You should give it a try, especially with just focusing on glass. You could do a "high key" or "low key" type of shot.

 

This book, Light - Science and Magic, Second Edition : An Introduction to Photographic Lighting, by Fill Hunter and Paul Fuqua,would be a good place to start for seeing how a photographer would setup and light someting like this (a photo of some wine glasses).

 

Also a background that starts horizontal for the model to be placed on and then slopes up in a curve gradually to a vertical position (I would think a mesh for this). You could have it just be white or put some texture/color on it. Then place 2 diffused light sources at a 45 degree angle to the object. I would even have the backround mesh give off a little light. I think with a setup like this you will get something that looks like a real photo product shoot.

 

Since I am not ready to try this yet on Lightwave (or other programs yet) it would be interesting to see what other people think about this approach.

 

Aaron

[otacon]

I used that approach for my wine glass render on the first page.

[bavanor]

and it looks great Otacon!

[IC]

I don't mean to be flippant bavanor but I think that's how most people set up these shots initially.

Most LW users have read or own a copy of Dan Ablan's Inside LightWave books where he goes into that setup. In fact, most books of this nature hone in on that technique.

The problem I find with it in transparent materials is there is no line or interest matter behind to highlight the refraction effect.

 

After a while you try other things and settle on something you like. There's just so many options in CGI.

[bavanor]

I wasn't trying to say anything bad about peoples techniques. I just have a lot more experience with real photography and was curious if people are trying some of the same techniques used there in 3d lighting.

 

I am picking things up in the 3d cg world again and am interested in the different programs and the way glass is used/rendered (because I will be focusing in on architecture).

 

Aaron

[IC]

I wasn't being touchy Aaron. I was just trying to point out that it's quite common to use the 'studio' setup in shots like these.

 

Here's one I did previously but as I said, it's hard to see the effects of translucency and refraction with nothing behind.

[Bongo51]

Bavanor,

 

I'm a professional photographer and CG artist, and unfortunately unless you use Radiosity, and even then, standard photographic techniques don't produce the same results which you would expect in the studio.

 

The only exception to this rule would be MaxwellRender which is a light simulator (also very slow and noisy currently)

 

Reflectors, softbox, colour gels are all difficult with Lightwave's native renderer (since they don't behave exactly as you would expect). You need to 'fake' your photographic set up to achieve the same results. Unfortunately it takes a bit of a shift in thinking to get results in 3D without having light bounce properly as in the real world.

 

fPrime will help IMMENSELY since it will allow you to tweak lighting in realtime and see the results near instantly, even with radiosity. I'd also recommend Maxwellrender if you absolutely must have photorealism. Though, it's pretty steep in the learning curve department and still is a bit buggy.

 

Regarding your 45/45 with a glowing background idea. This would only work with Radiosity, you should see similar results as photography, but with much more noise. Try setting the bounce settings to 2. It will increase render time but will help with noise and realism.

 

http://www.maxwellrender.com

http://www.worley.com

 

Ian

[bavanor]

Iain,

 

Maybe just turning the perfume bottle so it is not faceing the camera directly on as a front elevation. Try and turn it a little like the box (more perpendicular then parralel). Also, maybe putting in a thin vertical light that is lighting directly might put some highlights just in certain places on the glass.

 

I need to start trying things out again. And it helps to see these examples everyone has rendered.

 

Aaron

[bavanor]

Interesting to hear Ian. I will have to keep that in mind when rendering in 3d.

 

Aaron

[warprat]

here some more........................... I kinda like the first one, but the gradients keeep on making the thing dark like that.

I based my gradients on what u said iain The bottom is eyelvel and the top is the curve . and one more thing does the inside glass have any gradients???

[IC]

The first one is really good. Is the air object smaller than the glass one?

 

It helps if it is and it should have no gradients with everything set at 0% apart from 100% transparency and a very small IOR (e.g. 1.03). Use the same smoothing angle as the glass.

[warprat]

Well HEre is another try, I think I got the glass right this time, but.... My glass is hairy well filled with noise. and that was with the settings you told me iain which have worked perfectly, I have rerendered the little glass men and they did not have any noise. But this glass, well I have a skydome to light the scene I set just one bounce cos three made noise too, and set lighting quality to 1.0, no lights what so ever just the skydome. at this moment I am thinking of ditching the skydome and putting inimage world see how goes. Any suggestions regarding the hairy glass???

 

Thanks and CHeeeeeers!!!..........

[IC]

I think the 'hairy' stuff is your floor material refracted though the glass.

 

Nice.

[warprat]

thank you. well yeah, I thought that the glass was doing something with my floor. But then I adjusted a bit more and noticed I did not make the air a bit smaller, So I done that. tweaked here and the a bit, And rerendered and got this. The base is now black I am using image world now.

 

cheers!!!

[warprat]

Well I think I got it this time even managed to get to play about a bit hehehe. Please Comment.

cheers.................

[bavanor]

Warprat,

 

Niiiicccee, that looks so much better.

 

Now you are going to have to teach me all that you have learned with this experiment

 

Aaron

[warprat]

Why thank you......

I just have to thank Iain and everybody for their gret support on this glass matter,I really appreciate it. I learnt a lot from this and hope to share more.

no problem bavanor

 

Cheers.

[warprat]

Wonder why it's so quiet these days, Busy everybody? well amongst all the business inthe world Here I have done a little test here for everybody too,......critisize?