- Light at 3× the distance from the subject is 1/9 as bright.
- Light at 4× the distance from the subject is 1/16 as
bright.
THE FLASH HEAD (STROBES )
Invented in the 1930sby the electrical engineer Harold
Edgerton,theflashtubewasdevelopedinitiallytocapture
andrecordmovingobjectsonfilm.Itisnowamainstayin
theportraitstudioenvironment,whereitseaseofuseand
reliableoutputof lightis indispensable.There aremany
differentmakesandmodelsofflash kitsavailableto the
portrait photographer, all with their own benefits and
features; however almost all are built to similar
specification, offering ease of use in the studio.
Sync Lead or Trigger?
Allflashheadswillbesuppliedwithasyncsocketanda
synclead–whichistheconnectionfromthekeylightinto
thecamera,and the meansby whichthe lightis ‘fired’
whentheshutterispressedonthecamera.Intheportraiture
studiosetting,wherepeopleareconstantlymovingaround,
thephotographermayfindthatthelightsaresaferifthey
arefiredwirelessly,soastoavoidtrips,andalsoallowing
the photographer to move freely around the studio.
Many newer lighting kits will be supplied with built-in
syncsthatcanbefiredviaaradioorinfraredtransmitter
fromthehotshoeofthecamera.Alternativelyyoucanfind
infrared or radio triggersthat behave in the sameway;