Join Donovan Keith for an in-depth discussion in this video Shooting glass on a light background, part of Studio Lighting in CINEMA 4D.
In this video, we're going to light a glass teapot on a white backdrop. Here's our scene with the default lighting. Let's go ahead and give it a quick render to see what we've got. I'd say this is looking good because we've got good contrast between the white backdrop, as well as the unlit portion of our backdrop. The black of the floor is reflecting in the bottom part of our teapot. Whereas the white is being refracted and reflected on the edges. We've also got some good gradients between black and white. But even though we've already got a good looking image, this isn't the image we want. We need to find some way to light up our floor.
Let's go ahead and add a new light source. I'm going to name this Disc Light From Below. My strategy here is to create a disk shaped light that our object can sit directly on top off. Let's go ahead and click on this disk light and go to the general tab. Change the type from omni to area. I'm not going to turn on any shadows, which is a real luxury that we have by working in CG. In my details tab, I'm going to change the shape of my light from a rectangle to a disk.
And I'm now going to change the orientation of my light source to p 90, so that it's now pointing straight up. I'm now going to go into my four way view. And I'm going to relocate this object so that it's centered, under my teapot. I'm going to grab my move tool and my model mode. Grab that red axis and drag it so that it's lined up with the center line of my teapot. I now see that it's a little bit too large, so I'm going to take my scale tool, and click and drag to scale it down.
I'm going to stop scaling when those orange dots in my front view line up with the edges of my teapot. Rendering my scene now, I see this. It's very similar to what we had before, except it might even be darker. We need to find some way to make this light appear brighter. Well one way to do that is to first click on our light source, go the details tab and and activate Fall-off. I am going to choose Inverse Square Physically Accurate, which will have the effect of making those reading closes to it much brighter.
I am now going to frame each of my views by tapping the h key while I hover my mouse over them. This will allow me to see the Fall-off of my light source. Looking at my scene I see that my seamless backdrop is pretty large for this subject. So I'm going to select my seamless backdrop, and I'm going to scale that object down. And I'm going to stop when the edges of my backdrop are just out of frame. When I render my view now, I've got a lighter looking backdrop and I've got this beautiful gradient going from the center to to the edges.
However, the floor is still very dark. To correct that, what I'm going to do is turn on Global Illumination which will bounce some light off of my backdrop on to my floor. Go into your render settings and click on the check next to global illumination. If you are doing this in a scene from scratch, you would find this under the effects tab. Let's go ahead and give this another render. We now see that we have some light bouncing onto our floor and it's looking much better. I still want to adjust the brightness of my light a little bit. So I'm going to take this disc light, and my move tool, and expand its fall off radius just a bit, to really brighten up my backdrop.
And with any luck that will also find its way onto the floor. And it has. Now while this is looking pretty good I think that I might also want to take my disc light here and make it visible. So I'm going to turn on Show In Render and Show In Reflection. So that when we render it we see something like this. There's now a much brighter region at the base of my object. If you want you can continue to play around with the Fall-off settings for this light until you get a look that you really like. But for me this is going to be good enough to send out for a final render. Let's go to our render settings and go to the physical tab.
Change the sampling quality from low to medium. This is going to give us a smoother final result. I'm just going to press my Render to Picture Viewer button. And let Cinema 4D calculate my finished image. There are a number of different ways to successfully light glass on a white backdrop, and this is just one of them. The underlighting technique that we used works best with transparent subjects that are curved and refractive.
- Describing light
- Understanding the difference between real light and light in CINEMA 4D
- Using lighting direction to reveal form
- Adjusting light hardness
- Top lighting a subject
- Rendering reflective objects
- Shooting glass
- Separating objects from the background
- Hinting at a world outside the frame with gobos