The art and science of photography has come a long way since the days of chemically developed film. Modern digital cameras feature cutting edge technologies that allow virtually anyone to take superior photos with a minimum of effort and fuss. That said, even digital cameras need sufficient quantities of the right kinds of light in order to perform optimally, and this is where camera flash units really come into their own.
As would be expected, no two flash units are quite the same, and matching the right one to the type of photos that are being taken can and does make a big difference. This camera flash buying guide will educate readers and give them all of the knowledge that they will need to make informed decisions when purchasing their next flash units.
Built-in camera flash units are, as their name suggests, built directly into the physical chassis of the camera in question. They tend to be included in DSLR as well as compact cameras, and in many cases are limited in terms of their power. They are usually designed to lie on the same axis as the lens of the camera, and this results in the flash being reflected directly off of the subject. While this works in some situations, photographers that rely exclusively on built in flash will leave a lot to be desired in their finished products.
Also sometimes known as dedicated units, these fit into the camera's so-called hot shoe slot that is usually located on the top of the camera in question. Modern hot shoe units bring a whole host of benefits to the table, including superior levels of communication between the flash unit and the camera itself. Information is exchanged about shutter speeds, lens type, TTL, ISO, and much more. In addition to this, most hot shoe flashes can be angled in various directions in order to take advantage of indirect reflections, preventing red-eye effects and contrast issues. At the same time, hot shoe flash units tend to have higher power outputs than the built in variety, providing higher intensities and sharper images as a result. As if that isn't enough, some cutting edge models offer wireless controls that allow the photographer to use multiple hot shoes for the same picture simultaneously.
These specially designed flash units are made to be attached around the lens of the camera in question, and they provide an even level of light for photo subjects. They were created for macro photography projects in which very small objects need to be properly illuminated in order to pick up fine details. They provide well diffused illumination, which in turn allows the photographer to get in close proximity to the subject without suffering undesirable side effects. Closely related are so-called twin macro flash units which involve the use of several individually controllable flash units, providing an even greater level of control over lighting conditions.
These higher end flash units are so named because of their hammerhead-like shapes. These types of flash units are not usually coupled to the hot shoe of the camera, instead being attached to the side of the camera. This places the flash unit out of axis of the lens, and thus prevents against pesky issues such as red-eye effects. Because of their high-intensity flashes and elevated positions, they are of great utility for group photographs.
Next on the list comes studio flash units. These are usually high end units that are used in professional photography shoots and in studios. As would be expected of such devices, they put out superior levels of light, and are able to be combined with a wide variety of peripheral tools in order to produce specific kinds of effects for various kinds of photography projects. They can be used singly or in tandem with other studio flash units to create unparalleled results.
Many camera producers create dedicated OEM flash units that are made to work with specific camera models. This hasn't prevented third party manufacturers from developing their own proprietary flashes which are compatible with a wide variety of cameras. The fact that a given flash unit is OEM or third party does not in itself mean that the flash is superior or inferior to another model. Prospective photographers looking to purchase third party flash units would be wise to ensure full compatibility with their camera equipment before taking the plunge.
The amount of light that a given flash unit can put out is usually measured in it's GN, or guide number. The higher the guide number of the unit in question it, the more light it can deliver to the subject. It is usually considered advisable for individuals to acquire a flash with the highest GN possible. This is because while it's possible to get a high intensity unit and then reduce the output to fit the situation, it's not possible to get a weaker unit and then increase the intensity.
This characteristic refers to the amount of time it takes for the flash unit to recharge itself between discharges. Generally speaking, the faster the recycling rate is the more photos can be taken, thus increasing overall productivity.
Many of the better modern external flash units include a special feature known as AF assist. This is a special beam of light that the flash unit sends out before the picture is taken, which is read by a sensor on the camera in question and allows for fine adjustments to focus.
Most higher performance flash units will have the ability to swivel or tilt in various directions, and this allow the photographer to bounce the light off of surrounding features to produce specific effects.
This feature allows the flash unit to sense when the lens of the camera zooms in or out, and adjust the beam of the flash accordingly. This helps the photographer to get the best possible coverage in a given situation.
This hot shoe mounted flash unit provides modern features such as RF remote triggering and a bounce adaptor. Suitable for general use.
This is a straight forward hammerhead flash unit which is a good general purpose tool. Of value to serious and professional photographers.
This is a professional grade studio lighting unit, with two second recycle rates and fan cooling.