Flashes exist in many different varieties. Diverse variations of the basic flash have allowed almost any type of natural lighting effect to be imitated by this technology.
Guide numbers are a reference point for the power of a flash. The standard flash GM is 25 meters, but there are many other options to choose from.
Flashes with a guide number of 40 or 50 meters are preferred for high light photographing situations, like with bounce photography or long distance/wide angle shots.
Before we address the more advanced flash types in our next newsletter, take a look at the two basic and most popular kinds:
Auto Flash: automatic flash consists of an external sensor that communicates with the subject and the amount of light required for that specific picture. Even with automatic flashes, in some cases you will be required to input the distance from the subject and f-stop (aperture) that you wish the camera to operate under.
With these suggestions, the camera fires a flash of a specific duration that is cut off once the sensor makes a reading for optimum light. Some camera models that feature automatic flash will have suggestions for aperture and distance settings, highlighting the indicator in red if the input is off, and green if the numbers are right.
Manual Flash: a manual flash is the most basic type of flash. It is not controlled by the camera’s power, so you have to control all the necessary conditions and settings.
To use a manual flash you will have to input the distance to the subject, a correct shutter speed, and aperture (f-stop). Since the flash’s power is not connected to the camera, the camera will not give any indicative as to whether your calculations are correct. Because of this, thorough knowledge of these settings is necessary to obtain high quality pictures.
Now that we’ve discussed the two most popular types of flash, let’s take a look at some more advanced alternatives.
TTL Flash: TTL stands for “through the lens.” This refers to the flash’s ability to read lighting conditions through the lens, thus determining the correct exposure needed for a specific shot.
While most TTL flash units are used in modern SLR cameras, they can also be found in cameras with manual focus. In this case, inputting distance to subject or f-stop might be required. Because of the automatic reading of the TTL flash unit, no calculations are necessary. This allows for perfect exposure after every shot, even if you are using a light altering filter (like a polarizing or color filter) that would normally require light loss consideration.
If you are interested in purchasing a TTL flash, make sure that the camera format and type that you have allows this type of unit. Refer to your camera’s instruction booklet or consult a qualified professional for compatibility suggestions.
In many camera models, flash functions like fill and twilight are programmed into the system, so you have to input little to no data. These functions bear standard aperture and shutter speed measures for specific light conditions, making it easy to manage light conditions while taking a picture on the go or during an unexpected moment.
In most cases, you will only need to inset the distance to subject and the camera will do the rest. In others, the camera’s lens automatically measures the distance to the central object in the frame.
Stay tuned for our next newsletter, in which we will give you three basic pointers to make the best determination for your flash settings.