Using Flash Effectively
Flash units differ from manufacturer to manufacturer, but there are general guidelines that apply to basic flash photography as a whole.
Flash units are usually designed to fit on the camera’s “hot shoe”. The “hot shoe” supports and locks in the flash as well as connects it to the camera’s electric circuit. Almost all flash units made today have photocell sensors and thyristor circuitry that automatically control exposure when using the flash unit. These sensors vary the duration of the flash as the subject distance changes.
Since there are numerous flash units available on the market, it is important to read the manual for your flash unit carefully.
There are, however some basic guidelines that will make working with flash “user friendly”:
Reasons for Using Flash:
Improving Your Photographs with Flash
Environmental or Fill Flash – Usually, we think of the flash unit, as an aid only when there is insufficient light to record an image. But flash photography extends itself well beyond the limits of indoor events. Flash can be used to balance indoor and outdoor light; open up shadow areas on bright, sunny days, as well as provide bright details that are often lost in backlit situations. When flash is used outdoors, it is often termed “environmental" or "fill" flash.
Bounce Flash – In order to “bounce” flash, you must purchase a flash unit with a swivel mechanism, or manually point the flash towards the ceiling. Bounce flash occurs when the flash is directed towards a white ceiling, instead of straight at the subject. Bounce flash spreads light over a larger area. This simulates natural light and thus can be very effective. Bounce flash also eliminates the harsh shadows that are caused by direct flash. Usually, bounce flash requires 1-2 more stops of light than direct flash. Thus, if your direct flash f-stop is f8, bouncing the flash will usually require f4.
Why Bounce the flash?
The images below are examples of the benefits of bounce flash, especially when photographing people. Notice how the face in image 2 is much softer and pleasing to look at than image 1, which is taken with direct flash. The image with direct flash enhances facial lines and produces harsh shadows, which is not desirable in portraits of people. The light is more natural when the flash is bounced, and the faces are softer and more flattering. Don’t forget that bounce flash requires 2 more stops of light than direct flash. You will also get more effective results when using a white ceiling which is no higher than 8-10 feet. (Darker ceilings may require an additional stop of light.)
Flash units are usually designed to fit on the camera’s “hot shoe”. The “hot shoe” supports and locks in the flash as well as connects it to the camera’s electric circuit. Almost all flash units made today have photocell sensors and thyristor circuitry that automatically control exposure when using the flash unit. These sensors vary the duration of the flash as the subject distance changes.
Since there are numerous flash units available on the market, it is important to read the manual for your flash unit carefully.
There are, however some basic guidelines that will make working with flash “user friendly”:
- Since flash units depend on battery power to work, always make sure that your batteries are functioning properly. It’s also a good idea to keep a fresh set of batteries as a back up.
- Always set the correct I.S.O. number for the film you are using in both the flash calculator dial and your camera. (Digital cameras will set the camera ISO automatically once a flash unit is mounted on the camera.)
- Make sure your camera shutter speed is set at the appropriate one for flash. (Most cameras will synchronize correctly with a shutter set at 1/125, but some higher end digital SLR cameras will synch at higher speeds. It is important to check your camera manual). Shutter speeds that are slower than the designated speed can be used; but never those that are faster.
- Flash exposure is affected by the f-stop, not the shutter speed. Thus use the f-stop to control the flash exposure on the subject, and use the shutter speed to control the ambient light. (We will discuss this more in other lessons....)
- Make sure that your subject is within the distance range of the flash unit. Most flash units will not have any affect on subjects that are beyond 40 feet.
- When flash unit is on Manual Mode, always use the shutter speed that is noted on the flash calculator apposite the distance scale. When using flash on Auto Mode, the distance/f-stop scale will usually provide f-stop options for certain distance ranges.
- This option makes flash photography quite simple. You may, for example, be able to leave your camera f-stop at 5.6 throughout an entire affair providing your subjects remain within a distance range of 4-20 feet.
- Always make sure the LED light (ready light) on your flash unit is on before depressing the shutter. Flash units need a few seconds to re-charge between exposures.
Reasons for Using Flash:
- To provide adequate light levels in low lighting situations.
- To fill-in and open up shadows in high contrast shooting situations. E.g.: harsh sunlight, sun behind subject, subject in front of window, etc.
- To stop action. Direct flash will freeze action.
- To produce a special effect with double exposures and/ or motion.
Improving Your Photographs with Flash
Environmental or Fill Flash – Usually, we think of the flash unit, as an aid only when there is insufficient light to record an image. But flash photography extends itself well beyond the limits of indoor events. Flash can be used to balance indoor and outdoor light; open up shadow areas on bright, sunny days, as well as provide bright details that are often lost in backlit situations. When flash is used outdoors, it is often termed “environmental" or "fill" flash.
Bounce Flash – In order to “bounce” flash, you must purchase a flash unit with a swivel mechanism, or manually point the flash towards the ceiling. Bounce flash occurs when the flash is directed towards a white ceiling, instead of straight at the subject. Bounce flash spreads light over a larger area. This simulates natural light and thus can be very effective. Bounce flash also eliminates the harsh shadows that are caused by direct flash. Usually, bounce flash requires 1-2 more stops of light than direct flash. Thus, if your direct flash f-stop is f8, bouncing the flash will usually require f4.
Why Bounce the flash?
The images below are examples of the benefits of bounce flash, especially when photographing people. Notice how the face in image 2 is much softer and pleasing to look at than image 1, which is taken with direct flash. The image with direct flash enhances facial lines and produces harsh shadows, which is not desirable in portraits of people. The light is more natural when the flash is bounced, and the faces are softer and more flattering. Don’t forget that bounce flash requires 2 more stops of light than direct flash. You will also get more effective results when using a white ceiling which is no higher than 8-10 feet. (Darker ceilings may require an additional stop of light.)
Direct flash causes harsh shadows and enhances all facial lines. This type of lighting is not flattering when photographing people unless a specific visual effect is desired.
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Notice how the light has softened immensely when the flash is bounced off of the ceiling. In order to bounce flash effectively over a large area a white or light color ceiling is needed.
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Here are some good web resources for learning more about about working with flash...
Canon Digital Photography Forums
Below is an excellent video I found on YouTube with photographer, Phil Steele.
Canon Digital Photography Forums
Below is an excellent video I found on YouTube with photographer, Phil Steele.