Fear Of Flash
I learned two things over the weekend shooting - three if you count my continuing experiments in the studio.
First thing - People are frightened of flash. No, not just the persons who have been struck by lightning - novice photographers who go out to see stage events and hope to capture the colour and action with their DSLRs. They shoot away, look at the screen, puzzle at the dark images, boost the ISO, and shoot again. When they get the images back home they are still puzzled at the dark shadows but now they have an accompanying pattern of coloured dots in them. At this point some might become discouraged...and some might become Eduard Seurat...but there is a better technical answer.
Not Gordon, either - I mean flash on, and off your camera. Most of the modern DSLRs have provision for a dedicated flash unit as well as the in-built pop-up. The hot shoe has a pattern of computer contacts on the upper surface as well as a central firing contact. These pass information to and from the flash unit attached thereto, and the computer in the flash talks to the computer in the camera. Quite what they say between themselves about the operator is another matter, but at least there is agreement.
If you ask them to work in a TTL mode the flash will give a little pop to show the camera what the subject looks like, the camera will compare this to the overall light level that it can see, and then give the flash good advice as to how much more light to pop out for the main exposure. All within the time that the shutter is open. The result in most cases is a pretty good balance of exposure. Some subjects can jigger up the equation but then you can recover this later.
Main thing is where do you want to light to come from and what do you want it to see? Leading on to the second thing - Get that light up high and let it look down on the subjects. I shot belly dancers on Saturday night and the old problem of how to get enough light to the back line without blowing the sequins off the front line girls is easy to solve if you put your flash onto a Manfrotto monopod head and hoist it up on a Manfrotto light stand and let it see the the whole stage from up near the ceiling.
How do you trigger the flash up there? I used a 10 mtr coiled TTL cord running down to the hot shoe on the camera. ( Worked fine, which answers the question whether something that length will transmit TTL data.) If I had chosen to do so, I could have used a wireless radio control system from Pocket Wizard, or Hahnel. I could have set the on-board flash on my Nikon D300 to control the SB 700 flash by an infra-red link, but I wanted to try that coiled cord. Had I used a new Canon camera and new Canon flash I could have had in-built radio TTL....but then I would have had to buy all new lenses and a red bow tie as well...
Point is, that flash let me work at ISO 400 where my camera is comfortable, all the faces got light, and all the colour is real. I have had long experience of Perth stage lighting and unless Michael Edgely is plugging in the lamps and paying for the electricity, things can be pretty drab. Plus stage lighting colour is the opinion of the person setting the gels, and this may be entirely different from either mine or the dancer who has sewn her costume.
There was no mathematics involved. I changed the flashes for their mates at the 100 shot mark to let the batteries cool and the evening went swimmingly. I do not need to fight the computer at home to get good colour and none of the dancers will chase me up the street with scimitars.
Oh, that third discovery in the studio? Next blog.