Camera compatibility
Camera models that the flash can work with. Note that this parameter is usually indicated in the characteristics very approximately — only camera manufacturers are named, but there is no talk of models as such. Therefore, before purchasing a flash, it makes sense to separately clarify whether it will work normally with your camera — for example, on the manufacturer's website or thematic forums. This is especially true for devices from third-party manufacturers — for such models, the likelihood of problems is somewhat higher than for “native” flash cameras. At the same time, devices from the same company usually have the same requirements for connecting flashes, and therefore this parameter is with a fairly high degree of accuracy allows you to evaluate compatibility.
If the specifications of the flash indicate compatibility with several brands of cameras, this usually means that this model is available in several variations, each of which is designed for a different manufacturer.
It is worth noting that the "non-native" camera and flash may be quite compatible and work fine in most shooting modes. Nevertheless, support for TTL (see below) and a number of other specific functions in this case is usually out of the question, and in general, the reliability and efficiency of this combination is lower than that of a camera with a "native" flash. Therefore, it is better to choose all the same accessories with directly claimed compatibility.
Of t
...he compatible cameras currently in use: Canon, Fuji, Leica, Nikon, Olympus, Panasonic, Pentax, Samsung, Sigma, Sony.Reload time
The time it takes the flash or generator (for studio flashes) to prepare for the next flash. The smaller it is, the better. This parameter is especially important for continuous shooting, when the interval between frames is small: if you often shoot in this mode, you should look for a flash with the shortest possible recycle time. Also note that the characteristics usually indicate the shortest recharge time; in some operating modes, it may be significantly more than stated.
Pulse duration
The duration of the pulse of light provided by the flash. This indicator can range from thousandths to hundred thousandths of a second; it is usually expressed as a fractional number with a unit in the numerator, such as 1/880 s. The human eye does not notice the difference, but in some shooting modes it can become critical. For example, to capture fast-moving scenes (such as splashing water, the flight of an insect, or the movement of machine parts) you need to choose a flash with the shortest flash duration possible — otherwise the image may be blurry.
The longest pulse duration in modern photoflashes is about 1/800 s; the minimum value can reach 1/30,000 s or even less.
TTL
Flash units with TTL support. TTL is an abbreviation for "through the lens", i.e. "through the lens"; this is the name of the method of measuring exposure by the amount of light that passes directly through the camera lens.
In digital photography, TTL works like a pre-flash: before the main exposure, the flash fires one or more test flashes. The amount of light coming from the object being filmed is measured by special sensors, based on these data, the control electronics sets the necessary shooting parameters, after which the actual exposure takes place. This allows you to fine-tune the camera and get an image of optimal quality. The interval between the test and operating pulses is so small that it may not be visible to the naked eye at all (especially when the flash is synchronized with the front curtain or with a slow shutter speed).
Many modern camera manufacturers have their own developments and varieties of TTL technology, respectively, differing in name: for example, Canon has E-TTL and E-TTL II, Nikon has D-TTL (in early models) and i-TTL (in later ones) , Pentax has P-TTL, etc. Support for one or another variety is directly related to the compatibility of the flash with cameras (see above), and different formats are usually not compatible with each other.
Features
—
Autofocus illuminator. The flash has an auxiliary illumination function for the camera's autofocus system. Modern cameras overwhelmingly use the so-called passive autofocus systems that have one serious drawback: very low efficiency in low light and/or low contrast of the object being shot. The autofocus illuminator is designed to solve this problem: before focus, the scene is illuminated by a separate lamp, placed, in this case, directly in the flash body. This provides enough light for normal autofocus operation. Most often, backlight lamps give light with a characteristic reddish tint, however, in some advanced models, infrared illumination is used — invisible to the eye, but perceived by the camera. In addition, illumination systems can use a special light pattern instead of a solid beam, which further simplifies the task of autofocus systems. Anyway, the presence of this function is especially relevant given the fact that the flash is often used as a light source in low light.
— Control on the camera. The ability to change the settings for the flash using the controls of the camera itself, to which it is connected. In some cases (for example, with a wireless connection), this is much more convenient than switching attention from the camera to the flash.
—
Automatic zoom. The ability to automatically change the angle of dispersion of the flash light. For the angle of dispersion,
...see the relevant paragraph above, but here we note that this function provides synchronization between the flash and the lens: when the focal length of the lens changes, the angle of dispersion automatically changes. This provides the most effective illumination of the scene and at the same time relieves you of the need to manually re-adjust the flash to a changed angle of view each time.
— Manual zoom. Possibility to change the flash spread angle (see "Light spread angle") manually. This function expands the possibilities for "fine" tuning of work parameters and allows you to set parameters that are not available with automatic zoom (see above). In addition, it will be useful if you have to use several prime lenses with different focal lengths — the flash can be easily adjusted to each of them.
— Wireless control. Ability to wirelessly connect the flash to the camera or to another flash as master/slave (if available, see below). The format and specific features of such a connection may be different: wired connection, IR channel, radio, etc. Wireless control is indispensable if the flash must be placed away from the camera; it also makes it easier to create multiple flash systems for optimum lighting. These features are especially useful for studio shooting (although it's not limited to this).
— Work in master mode. The ability to operate the flash as a master flash for a system of multiple flashes. The entire system is controlled through the master flash, the operation parameters of the slave flashes are set, and the command to fire is given (note that the master flash itself may not fire at all). If you plan to shoot using a multi-flash system, you will definitely need a model with this function — without it, creating a system is impossible. Of course, master and slave flashes must be mutually compatible; this point should be clarified separately.
— Work in slave mode. The ability to work as a flash as a slave in a system of several flashes. In this mode, the device is connected to the master flash and fires on command from it. For more information on flash systems, see "Master Operation" above.
— Diffuser. The colour of the diffuser supplied with the on-camera light source (see "Type"). Colour can be: orange, white, pink or yellow.
A diffuser is a special filter designed to scatter light from individual LEDs, and also, in some cases, to give it a certain colour and change the colour temperature.
— Radio synchronizer. A device designed to wirelessly control a flash or a set of flashes (if each has its own receiver). Usually a separate module installed in the hot shoe; on command to fire, this module sends a radio signal to all receivers tuned to it, ensuring synchronous flash firing. At the same time, some models of luminaires with such a function are capable of receiving via the radio channel not only the start signal, but also the operating parameters (primarily the duration and power of the pulse).
