So here’s the rub: On digital cameras many filmmakers skew toward slight underexposure in order to preserve highlights. Although underexposure in the digital world is a fantastic technique for both protecting whites and achieving great-looking velvety blacks, this is not the case with the Red One. When you underexpose the Red One you essentially waste linear bits of metadata the camera could have captured. When you open up underexposed Red One footage in the raw conversion, you end up with digital noise, milky blacks and posterization. Posterization is the undesirable concept of spreading too little continuous information too far apart in a digital camera’s linear range, resulting in bands that run across the image, particularly at the points when two colors without sufficient tonal information meet.
An example of digital posterization above shows more digital noise on the right, which lacks exposure, versus the left side, which has more exposure, therefore more information for a digital sensor's linear range.
So what is the solution to nailing exposure on the Red One?
I begin the process with my old, trusted light meter, then use the Red One’s many digital modes to help fine-tune the camera’s proverbial sweet-spot exposure, in order to capture the cleanest digital image possible.
I expose precisely at the Red One manufacturer’s recommended 320 ASA index rating for its sensor.
I then set my light meter to 320 ASA and determine my T-stop via digital exposure rules, primarily exposing for my key light.
I access the histogram mode on the Red One monitor to determine whether my exposure has placed highlights as close to the right side of the histogram as possible. Exposing to the right is the single most important trick to ensuring you have no digital noise contamination in the mid-tones and shadows. If nothing touches the right side of the histogram, I ignore my pre-determined light meter’s reading, and open up the lens T-stop until the values move as far over to the right as possible without having clip issues.
With my lens T-stop now determined, I get out my light meter to check my key to fill light ratio. For the most dramatic scene requiring the fullest tonal exposure range from pure whites to pure blacks, I expose with my fill light exactly two-and-three-quarters of a stop under my chosen T-stop. This creates the precise amount of detail I require for Red One linear exposure range, ensuring I have great-looking blacks in my shadows and detailed, pure unclipped whites in my highlights.
I check my exposure one last time by activating the Red One’s false color mode to make sure no important information I require is pink. Any pink color in this mode tells me I am overexposing the Red One sensor. At this point if I see pink I will not adjust my camera lens T-stop, but use grip gear or graduated filters to bring back the overexposed areas into acceptable exposure zones.
In my experience any Red One build 16 or onwards has a noise floor that is vastly improved over Red One build 15, so it’s a no-brainer that you should upgrade.
On either digital or film shoots I use an incident light meter to determine lighting ratios.
