Old School Flash Photography
When I first began to get into photography, I was a child; flashguns were something that fits into the camera’s accessory shoe. It was connected to the PC socket using an untidy cable. It was the most sophisticated version. The PC cable wasn’t needed for the camera, and the flash came with a hot-shoe connection. The only thing it could do was to produce an intense flash of light that was timed to coincide with the shutter of the camera being fully open. The technique of photography with flash was a matter of calculations and guesswork adjustments.
The biggest issue in film photography is the light effect is not visible until the print is taken. Furthermore, the location where the flashgun is attached to the camera is not optimal for certain types of photography, like portraiture, for instance, as it creates a soft light and creates unsettling shadows. The best results are therefore dependent on photographers to know how to work with this setup. This knowledge comes from careful experimentation and knowledge.
There are two components for successful flash photography on film. The first is the correct exposure. Each flashgun comes with a “guide number” for every speed of film (although the number for 100 ASA/ISO is the most often utilized). The number is determined by the flash’s firing at the object directly. The more guide numbers are higher indicates how effective the flashgun is; however some manufacturers have tended to exaggerate the potential of their flashes. It is essential to be aware of the guide number of your flash.
The second element necessary to calculate the proper exposure is the distance the subject is to the lens. If you are using direct flash on the aid of an SLR or rangefinder lens, this measurement will be simple to determine. The calculation of exposure is the guide number multiplied by distance. The result is equal to the aperture required.
Guide Number = Aperture
If a flashgun has a maximum guide number of 80 while the target is located 10 feet away, the recommended aperture is eight f/8 (80 10). The shutter speed must be minimal, given the requirements for synchronisation of flashes in the focal flat shutters (i.e. generally 1/60th of seconds). When using leaf shutters, it’s possible that the speed of the camera does not exceed the duration of the flash (but with the typical electronic flash durations of around 1/10th of a second, this shouldn’t pose an issue).
Some flashguns feature a small exposure guide table that is printed on their casings and shows the proper F-stops for a variety of lengths (the computations have already been made by the user). Other flashguns feature a “calculator wheel” where distances (and speeds of the film) are dialled in, as well as a suggested aperture, is displayed (in a similar fashion to an exposure meter that is held in hand). Some flashguns also require users to work in meters instead of feet.
Anyone who is serious about photography with flash might want to try out the flash they own and make a set of exposures that are bracketed from an experiment image (i.e. with varying the f-stop employed), which allows recalculation of the actual guide number for their camera by analyzing the best exposures of their test prints (i.e. distance + aperture = guide number).
Additional exposure calculations are required when using the flashgun outside of the camera or when the output of the light is altered in different ways. These techniques can enhance the efficiency of a basic flashgun.
A few of the best (yet still essential) flashguns feature articulation of the window that produces light. The articulation is usually tilted by approximately 90 degrees (i.e. it is pointed at the subject straight up, with any angle between), or the device rotates one side of the other (and occasionally, they perform both). This permits light to be bounced off of a nearby reflective surface onto the subject. The bounced light is a more diffused appearance and casts softer shadows. The direction it is pointing (from above or to one side) will be more natural light. The reflective surfaces that are suitable for use should be white in order to not introduce a colour shadow to the lighting. Ceilings are typically the best option. The photographer should focus the flash to the approximate point at which the light is reflected back towards the side of the object (somewhere in between camera and subject).
Adding the total distance from the camera-to-reflector to the distance from the reflector-to-subject and dividing the guide number will roughly determine the aperture size required. A small amount of light will be lost, and the aperture will need to increase by one to two stops: How much additional exposure will be given is an issue of judgment from experience.
If a camera does not include tilt or swivel capabilities and is not tilt- or swivel-capable, it can be used with the camera. This setup comes with a few disadvantages. The flash has to be placed on the tripod (cold shoes that have an adjustable tripod bush are available). Additionally, it is necessary to connect the camera to the flash through a long trailing lead. A better illumination can be accomplished when the source of light is located away from the camera located at an angle towards your subject (with or without bounce). Similar to bounced flash, one thing to remember in this case is that flash photography can be done even at low light levels. Moreover, there is often natural light. Moving a flashgun from the camera permits it to be put in a location where it won’t produce shadows that are in conflict with the lighting source. Sometimes, a highly powerful flashgun may not be the most effective tool.
Certain flashes have a white semi-transparent diffuser. If you are purchasing second-hand equipment, these components are usually not included, but it’s possible to create an alternative at home with similar materials such as paper towels held by elastic bands that can be used to achieve similar effects. This diffuses light and also reduces the intensity of the flash, thus reducing hard shadows.
The same as before, exposure determination begins with dividing an amount of guide by the distance to calculate the required aperture and then by adding an additional f-stop (or two) dependent on the size of the diffuser and the experience. It is also possible to simultaneously diffuse and bounce flash.
Other ways to utilize flash
I’ll mention this in this article since the topic is large enough to warrant another article. However, there are a variety of ways that a basic flashgun could be utilized (rather than just placing it onto the camera and then pointing it directly at the object). This includes outdoor flash, fill-in Flash as well as making use of more than one.
Being proficient with flashguns requires experience through experimentation. However, there are a few basic rules to follow that, if adhered to, can eliminate some of the confusion and put you in the realm of a well exposed and well-illuminated shot.