Flash photography basics Timothy Swinson
What I will be talking about Basic intro on TTL flash vs Manual Flash How TTL flash works How manual flash works Getting the flash off the camera for better results Hard light vs soft light Modifying the light source Some of my own example photos
The Very Basics Flash is an artificial instantaneous light source. Used to create light where the normal light isn t sufficient for your uses. 2 main types of flash control and usage, TTL (through the lens metering) which is an automatic mode and manual control.
TTL Flash Most common type of flash usage Camera will automatically determine the power of the flash it thinks is needed Works by the camera firing 2 flashes, the first to meter the correct exposure and the second to create the exposure. Easy to use as the camera controls and sets the flash. Great for moving subjects.
TTL Continued Problems I have with TTL flash. Inconsistent exposures this can be fixed with using flash exposure compensation. Similar to using exposure compensation in aperture mode or shutter mode. Often you will need to take 2 shots to dial it in unless you are good at judging exposure. If you change composition your exposure may change.
Example TTL normal exposure
Example TTL with compensation
Example TTL Change Composition
Manual Flash Consistent exposures No need to use expensive TTL flashes Can use other manufacturer flashes (eg: Nikon flashes with a Canon camera) Same techniques apply to studio lighting Not as suited to moving subjects as TTL
Using Manual Flash Controlling flash power with the flash unit (demonstration) Physically change the power level of the flash. Usually measured in fractions. (1/1 power to 1/128th for example) Move the flash closer or further away from the subject. Inverse square law double the distance from the subject and lose 2 stops of light.
Using Manual Flash Continued Controlling flash power with the camera Remember, flash is an instantaneous light source. Shutter speed has no effect on flash because shutter only affects continuous light sources(one exception sync speed! Very important!) Aperture physically blocks light so it can control the flash. ISO boosts or lowers the brightness of the light so it can control flash.
How to meter flash exposure Using the flash guide number in conjunction with inverse square law (not really needed) Using a light meter Using the LCD screen on your camera and the histogram to judge exposure
Getting the flash off camera! On camera flash works fine but it gives that deer in the headlights flat/boring look. Moving the flash away from the camera lets you introduce shadow into the photograph. Shadows help create depth, shape features and create emotion. They help make a photograph appear more 3D.
Getting the flash off the camera continued Direct flash
Getting the flash off the camera continued Flash moved off to the left
How to get the flash off camera Hotshoe Cable PC-Sync cord Optical slave Manufacturer IR control systems (Canon wireless, Nikon creative lighting system) Radio Triggers
Hard light vs soft light The hardness or softness of the light is characterised by the transition gradient between the shadow and highlight portions of an image. Hard light has a very dramatic transition (sometimes almost none) between the shadow and highlight. Soft light has a more gradual transition. Both look different and can be used for certain effects.
Hard light vs soft light continued Soft light (left) Hard light (right)
Modifying the light source Change the way the light acts or looks Create softer, harder, more directional or more dispersed light Each has their place and effect, it is up to you to decide where to use it. Examples: walls, umbrellas, softboxes, snoots, gobo, beauty dish, grids, barn doors, the list goes on.