What do I need to know before start shooting chroma?
We are going to discuss every detail in shooting chroma key, and chroma key studio setup, Users of all level, will be able to use this technique. However I do recommend you take some time to get to understand your camera first, it’s important to understand your camera , Aperture, shutter speed, depth of field and knowing focal length, So having basic knowledge of how to control your camera is important and we try to cover everything else later as we go further.
So first let’s understand why we want to shoot on the green background? As everybody is shooting with white background grey background,
Its all about the flexibility chroma green background provide us and cut down post-processing time.Many people use off-white gray background and that is also fine in studio photography, People listen green and they think of cheesy special effect and that is true at some extent as its very easy.
The main reason we use green screen is opposite of our skin tone and it’s easy to pull a key without using third party software or lots of masking so that it will be easy in post-processing.
This also has benefits for those who are in an advertisement or special effect industries; Now wedding photographers are also using the chomp key as its provide great flexibility in post-processing.We cannot only change the background in chroma key setup but we can change the lighting depth of filed too,
Just imagine you shoot the background separately and composite it later with the subject.
Chroma blue or chroma green ?
As we see the color wheel, green is opposite of skin tone so when you start removing the green color, you don’t disturb the skin tone and that works very well with the sensitive video camera too.
So when we use the blue chroma ?
Blue works well when free is not an option, though blue has less noise in film workflow, But when dealing with video the only reason to use blue background if your subject and your clothing choose has lots of green.
Chroma key Studio setup
Now let’s talk about setting up chroma key studio setup.
The first thing you need is bigger space or bigger studio and that is important, Why we need bigger space?
We need bigger space for couple of reason,
you can control the distance of your subject to your green screen and your camera, If your subject is too close to the green screen he or she is gone get spill reflecting on them, and there can be a problem with the shadow also.
So the longer space you have, the easier it will be shooting, post-processing and compositing.
If you are shooting still chroma green key you need not worry about sound, But if you are shooting video you need to make sure the space you select or choose for your chroma key video setup is quite and noise free. Otherwise, you have to spend on sound equipment and noise reduction too.
Choosing the right chroma green screen background
One of the standard green backdrop used in aroma key is cloth fabric; People gets hung on some special brand or unique fabric, there are so many options when it comes to choosing the background.
Just make sure whichever cloth you use it does not have the wrinkle on it, Like muslin or cotton backdrop, Wrinkles are very problematic when you are going to key something because you want even to lit it.
Setting up the chroma key lighting
Here we are going to use the three-point lighting system.
First light is for the subject, and We will use it to lit the subject on 45D angle We will call it key light,
The second light which will control the shadow which caused the key light, its called a fill light It will soften the hard shadow,
The third light we call it back light or hair light, We use it to make a separation between subject and background, Its possible you may not have the three light with you if this is the case you might want to use the reflector. Normally people use the softbox on the light but if you don’t have the softbox or you have speed light where you cannot put the softbox using the umbrella, any kind of diffuser will work here.
If you need want more detail setting up the light check our three-point lighting setup blog
Lighting the green screen background
you need to lit the green screen evenly,Make sure there is no light variation on the background , for this you need two more light other then your subject,
Achieving 100% perfection in even lighting is not compulsory you can tweak it little on post-production but try to capture it correctly in camera.
Click here if you want to learn how to edit the chorma key in Premiere pro