Lighting for photos and video at home: kelvin and CRI

In photos and videos shot at home, true colours and natural-looking faces depend on the colour, quality and position of the light. Simple setup rules explained.

Product photos, online lessons, video calls and short clips for social media are now shot at home in ordinary rooms. Even with a good camera the results often disappoint: faces look yellow or blue, odd coloured patches appear in the background, and horizontal bands roll across the video. Most of these problems come down to light, and they can be solved without expensive studio gear.

The golden rule: one colour temperature per scene

A camera sets its white balance for one light source. When a scene has two differently coloured lights, such as cool daylight from a window and a warm ceiling bulb, the camera can treat only one of them as “white”. The result is a face that is bluish on one side and orange on the other, which is very hard to fix in editing.

So the first step is to bring every light in the scene to the same colour temperature. There are two ways:

• if you are shooting in daylight, switch off the room lights or replace them with neutral-cool bulbs close to daylight;
• if you are shooting under artificial light, close the curtains and use only lamps of the same type.

Which kelvin you choose is secondary, because the camera will adjust white balance. What matters is avoiding a mix. In practice, neutral light around 4000–5000K is a comfortable starting point for skin.

Colour rendering: CRI affects the camera too

The eye partly adapts to poor colour rendering; a camera does not. In a picture taken under a low-CRI lamp, skin can look grey-green and red products brown, and colour correction cannot fully restore them. For photo and video, choose light sources of Ra 90 and above. Video work sometimes also uses TLCI, an index developed for television, but for home use high CRI is a good starting point.

Flicker and banding in video

Some LED bulbs and fittings run with a rapid flicker that is invisible to the eye. You may not notice it, but a camera does, especially with short exposures: dark bands roll from top to bottom in video, and in a burst of photos one frame comes out darker than the next.

It is easy to check: point a phone camera at the lamp and see whether bands appear on the screen. If they do, you have two options: choose a flicker-free light source, or set the shutter speed to match the mains frequency (on a 50 Hz grid, usually 1/50 or 1/100 of a second). Dimmed LED lamps are more prone to flicker, so keeping lights at full output while filming is more reliable.

Soft light: a large source, close by

A small bare bulb creates hard shadows and bright reflections. For faces and products, soft light looks much better. To get it:

• bounce the light off a white wall or ceiling and shoot with the reflected light;
• put white fabric, tracing paper or a matt diffuser in front of the lamp, at a safe distance from it;
• bring the light source closer to the subject, because the larger the source relative to the subject, the softer the light;
• if you use window light, choose light filtered through a thin curtain rather than direct sun.

Where to place the lamps

The most common mistake is shooting with ceiling light alone. Light from above creates shadows under the eyes and nose. A simple, effective setup is:

• key light: in front of the face, slightly to one side (up to 45 degrees) and a little above eye level;
• fill light: from the other side, weaker; a white card or a wall can do the job instead;
• background light: a soft light behind the person, warm or coloured if you like, to separate them from the background.

For video calls, the simplest solution is one soft lamp behind or beside the monitor, aimed at the face. There should be no window behind you, because the camera exposes for the window and your face stays dark.

Two settings on the camera side

Once the lighting is set, switch the camera from auto white balance to a fixed value. Auto mode can keep shifting colour depending on what enters the frame. If possible, lock exposure too, so brightness does not jump from shot to shot.

Before you start shooting, run through these questions:

• Is there only one type of light in the scene?
• Do you know the CRI of the lamps?
• Do bands appear when you look through a phone camera?
• Is the key light in front of the face, or only coming from above?
• Is a window or bright lamp behind you in the frame?

Zəfər İşığı is the LED lamp brand of Ganja-based Zaferoğlu Elektrik. You can compare lamp types for a home shooting corner in the website catalogue by cap and shape.