There are many different 3d programs, but I primarily use 3ds Max. Working at ExaroMed I am very lucky to work for an Art Director that is always willing to help me become a better artist. Last week, Scott and I took some time going over some lighting parameters within Max, to create more realistic light sources that will help my models have more 3 dimensional shape. 3 point lighting is what I was taught in my graduate program, but not only is the placement of the lights important, but what you do within the lighting parameters that really helps give off an effect you are aiming for. Do you want a cooler or a warmer looking scene? Before lighting a scene you have to take into consideration where the scene taking place. Are you outside or inside? Is there natural, florescent light or both? Common sense right, but sometimes you can get caught up in a project and forget to think about these things, and this is only thing I am always working on to improve.
Lets go over 3-point lighting really quick. Ok, you have your Key Light, Fill Light and Back Light. When placing your lights I usually like to use my Top viewport for placement. Then I like to choose the side views to raise or lower the lights depending on the effect I am going for. Typically I will use spot lights as opposed to omni lights because they can increase render time.
1. Key light – main illumination and is the dominant light source. A spot light or mr spot light can usually achieve the feel of sun light, lighting coming through a window or florescent lighting. Offset the light 15-30 degrees to the right or left of your camera. Also, either raise or lower your lights instead of having it straight on your object.
2. Fill light – Secondary light source, softener, and makes object more visible. This light can simulate the sky or room in general as opposed to the key light being the sun or main light source. I also use spot lights for this, and you can use more than one to light your scene. Place the fill light opposite to the key light, so if the key is on the right, than place the fill on the left.
3. Back light – Also known as, Rim Light. This light can create a edge around the object. Scott recommended changing the color of the back light to create different effects. For example, if you change the light from white to a purple or blue color and turn up the intensity, you can create a warmer effect.
Once you have your lights positioned, the next part is playing within the light parameters. The example I have above of an HPV model I made. I’ll go through the parameters that I changed:
1. General Parameters> I checked the shadows box> within the drop down menu I selected the Ray Traced Shadows for a softer shadow. You can diffuse the edge of the shadow for a softer effect. Warning: Shadow maps can cause flicker effect if you use for animation.
a. Key light – Multiplier: 0.8> changed color to light yellow color for more natural warm light.
b. Fill light – Multiplier: 0.3> used a yellow color as well
c. Back light – Multiplier: 1.4 for more intensity> changed to a purple color to accentuate its complimentary color
d. Near and far attenuation – Can create a fall off of shadow
3. Spotlight Parameters – I increased the fall off to soften the spot light edge on all the lights
4. Advanced Effects – I didn’t change anything here, but if you wanted to add a overall glow to your scene you can uncheck the diffuse and specular and check the ambient only box.
5. Shadow Parameters – I softened the color shadow to a darker grey and turned down the density to 0.8.
6. Area Light Parameters – I changed the type from Rectangular to Disc. Changed the radius from 1.0 to 150 or higher for softer more realistic shadows that naturally fall off.
Being a medical animator, using your lighting to convey a mood can be very helpful, so experiment. Go nuts. Also just a quick guide to what certain colors can indicate:
1. Red light – danger, can bring attention to something
2. Blue or Purple light – Good for dark lighting, can create a cool microscopic environment
3. Green light – Bad, infected, avoid