Real world meets lab
All lights were tested under strict conditions to ensure an accurate comparison would be possible
Each light was set up in our test lab. To test the relative power of each light, we fitted them with standard reflectors, but no modifiers, and measured the intensity of light at a distance of two metres. This was done with a Sekonic L-758D Digitalmaster light meter, set to flash mode for the flash heads and incident metering mode for the constant lights. Measurements were taken throughout the range of available power settings for each light. For halogen lights we also measured the light intensity with different wattage bulbs (where available) and at either end of the zoom range. Our table shows power ratings in terms of the aperture required for a correct exposure, using a sensitivity of ISO100 and a shutter speed of 1/125 sec. For flash heads, the recycling time was measured from immediately after discharging a full-power flash until the head was ready to fire again.