Chroma Key Tutorial: 3 Tips For Chroma Keying Animals
Anyone interested in video special effects can benefit from reading a chroma key tutorial. It’s a challenging effect that needs to be properly executed in order for it to work. And, shooting animals is in it’s own right a challenge as well. So, what do you do when you have to shoot animals for chroma keying shots? Here are 3 steps to help you out.
1. Think Outside of Green
Most chroma keying is done on green and blue screens, but for shooting animals, these two colors aren’t always practical. Animals come in all sizes, shapes and colors, with a few of them being green and blue. So, to compensate for this, you need to pick a color that contrasts with your animal.
Chroma keying does not need to be done with blue and green, it can be done with any color. Those colors are just used because they work well with humans. But, anything you pick can be keyed out as long as it is evenly lit so that it’s color is consistent. If you’re shooting multiple animals, then you should schedule the shoot in the order for the color of your screens. First, do all the animals against the orange background, then the ones that need purple and so on. A lot of animals are covered in fur, which means that the keying out needs to be very precise due to the fine hairs on their body. You need a color that contrasts with them so that the fine hairs of the animal aren’t accidentally keyed out.
This effect works by selecting a specific color to key out and then setting a tolerance. The tolerance setting will key out colors very similar to the one you picked, which in theory is the shaded areas on the green screen. In reality though, it is very easy for part of your subject to be keyed out as well. So, pick a color that contrasts with the animals fur so that no parts of it fall within the tolerance of the color being keyed out.
2. The Lighting Needs to Be Perfect
Just like all chroma key shots, the lighting of the background needs to be perfect so that the color is consistent throughout. Poor lighting creates many different shades of color, which makes the keying out process more difficult then it needs to be. It is a lot easier to light a green screen properly on set than it is to fix a poor green screen shot in the editing room.
3. The Green Screen Needs to Be Big
Animals do whatever they want and will probably not sit still at their marks. Compensate for this by using a big background so that if the animal moves a little, you can compensate.