How to calculate the wattage I need for my studio space?
The wattage you need depends on the size of your space, how far the light is from the subject, what modifiers you use, and your camera settings. A small home studio needs far less power than a large commercial space. Here is how to calculate what you actually need.
General wattage guidelines
Small home studio (2×3m, close subjects): 60-100W COB light is sufficient. At 1-2 meters from the subject with a softbox, this provides plenty of light for both photo and video at ISO 100-400.
Medium studio (4×5m, portraits and products): 150-200W COB light as key. This handles larger softboxes (90-120cm) and gives you headroom to use lower ISO and faster shutter speeds.
Large studio (6×8m+, groups and full-body): 300W+ COB light as key. Large spaces mean the light is further from the subject, and light falls off with distance (inverse square law).
Outdoor fill / competing with daylight: 500W+ to match or overpower sunlight. Daylight is extremely bright — indoor studio lights need serious power to compete outdoors.
Factors that affect how much wattage you need
Distance: Light intensity drops dramatically with distance. Moving a light from 1m to 2m away reduces brightness by 75% (inverse square law). Further distance = more wattage needed.
Modifiers: A softbox absorbs 1-2 stops of light. A beauty dish absorbs about 1 stop. A bare reflector loses almost nothing. Budget extra power for your modifier.
Camera settings: At ISO 100, f/8, you need much more light than at ISO 800, f/2.8. Video at 1/50s needs more light than a photo at 1/200s.
Color temperature: Bi-color LEDs produce less light at the extremes (full warm or full cool) than at their midpoint. Budget 20-30% extra for extreme color temperatures.
COB lights by wattage at Camera Shop Egypt
The practical test
The best way to know is to test. Borrow or rent a light, set it up in your space with your modifier, and check the exposure at your typical camera settings.
Rule of thumb for video: In a small space, 100W with a softbox gives you comfortable exposure at ISO 400, f/2.8, 1/50s. If you need ISO 100 or f/5.6, double the wattage.
Rule of thumb for photo: Photography is more forgiving because you can use flash/strobe (which delivers much more instantaneous power than continuous LED) or slower shutter speeds on a tripod.
Always buy slightly more than you think you need. You can always dim a powerful light, but you cannot make a weak light brighter.
For a home YouTube/podcast studio, a single 100W COB light with a softbox is more than enough. Do not overbuy — 300W in a small room is like bringing a firehose to water a plant.
