Automatic Mode/Automatic Exposure: As a professional photographer you would, of course, never have to use the 'Automatic' mode on your camera. Here is why you should especially not use it when shooting with lights - the automatic mode relies on the cameras TTL (Thru the lens) metering system which is unable to detect the flash that will come from the lights, so the auto settings will be wrong and will result in horribly over-exposed images.

Available Light: Available light or sometimes referred to as ambient light is light that is already present where you plan to shoot such as the Sun or domestic lighting.
Usually, when you are using studio flash unit, the available light will be overpowered by the direct flash. You should switch off any ambient lighting and block out that nasty sun before taking meter readings or at least remember that the other light is there and take it into account.

Bounce Lighting: Bounced lighting can be used to create a very soft fill-in light using products such as the reflex panels - which can be used in portraiture, indoors our outdoors, to reflect light from flash or even the Sun to fill in shadows. You can also bounce light from ceilings or white walls to achieve the same soft effect..

Bracketing: Bracketing is when you take several versions of a shot at exposures either side of that determined by the flash meter giving different levels of exposure. It is good practice as, even with today’s advanced image tweaking software, if when reviewing your pictures you decide the image should have been slightly over or under exposed you will already have those images and not have to set the shot up again. Some generators have auto bracketing options built-in to make photographers lives simple.

Color Balance. Usually for film. This refers to the lighting conditions to which the film is designed to record images, typically expressed as either daylight (5500K) or Tungsten (3200K).

Color Temperature. Color temperature is a way of defining the color of a light source - usually referred to in Kelvin. The Kelvin absolute scale defines the temperature to which a black metal rod would need to be heated to match the color of the light source.

Contrast: Contrast is the difference between extremes of light and dark in an image. High contrast is when there is a very sharp difference between the lightest and darkest areas and not much in-between. F&V manufacture several reflectors which can be used to create high contrast and high key images.

Depth of Field: Depth of field is the distance between the nearest and furthest parts of a subject which can be recorded in an acceptable focus at one setting of your camera. Depth of field can be increased by using a smaller aperture so that more of your image is in focus, conversely if you use a larger aperture you will decrease your depth of field so that only one part of your image will be focused with the rest of the image blurred - which is a popular effect.

Diffused Light: Diffused light is often very soft and even with very minimal shadows. The best way to achieve diffused light is, as the name would suggest, to use a diffuser such as a softbox, or by removing the silver cover of a umbrella and shooting through the white diffuser material.

Fill Light: The fill light is designed to fill in areas not covered by your main light so that you do have glaring and very obvious shadows in your photo. Fill in light can be created by using flash or just be reflecting ambient light using a reflex panel.

Filter/Gel: Filters and gels fit over the light source to change the color or quality of the light. Many reflectors are designed specifically to be used with Gels and Filters – F&V also manufacture the Multi clip which can be used to attach gels and filters to just about anything.

Flash Duration (t=0.1, t=0.3, t=0.5): When a studio strobe 'flashes' the flash tube turns on very quickly and then dims gradually as the flash capacitors discharge. If your subject is in rapid motion then you will need a fast flash duration to prevent your image being blurred. Because the light emitted by the dimming end of the 'flash' does not really contribute to the exposure, we do not rate flash duration as the entire time the flash tube is on - instead, when you read out technical specifications you will not that we use t=0.5 which is the amount of time that the output of the flash is above half of the peak value. t.1 is the time during which the output is above 1/10 of it's peak and t.3 is the time the output is greater than 1/3 peak.

F-stop: F-stops are an international standard sequence of numbers which express relative aperture - lens focal length divided by the effective aperture diameter. Each change of F-stop halves or doubles the image brightness, as you 'step' up or down.

Guide Number: The guide number of a flash gives you an indication of what f-stop to set your camera to given the distance of the subject from the light source To do this you simply need to divide the guide number by the distance between your flash and subject. The distances are usually measured in meters.

Hot Shoe: The hot shoe is an accessory shoe built into the top of most professional cameras incorporating electrical contacts which allow you to usually add flash guns designed by the camera manufacturer. F&V use the hot shoe to mount our Radio Trigger which allows remote flashing of our lights via a radio signal so you don't need sync cables.

Hot Spot: A hot spot is an area in the middle of a pool of light where the light is very intense - hot spots can be eliminated by using diffusers. Some accessories include special diffusers which are printed with a complex pattern to ensure that light is distributed evenly across the subject eliminating the hot spit all together.

IEC Standard Connector: These power cords are found on just about all computer equipment and are commonly referred to as 'kettle power cords'. This connector system is used on F&V equipment.

ISO: International Standards Organization. In Photography the ISO 'number' usually relates to the speed of film (or equivalent on digital cameras). The lower the speed of the film the more light is required. So in the same way that you need a fast flash duration to capture movement, you would need a higher ISO speed.

Joules: Joules are a measurement of output, rated the same as watt seconds (Ws). At F&V we always refer to the output of a unit in Ws.

Kelvin (K): The Kelvin is a unit of temperature measurement devised by the scientist Lord Kelvin. It starts from absolute zero at -273 Celsius. Degrees Kelvin (or color temperature) is used to measure the color balance of light emitted from a light source. The Kelvin absolute scale defines the temperature to which a black metal rod would need to be heated to match the color of the light source. Sunlight measures about 5500K and film balanced for sunlight (daylight film), will assure 'true' color rendition for objects reflecting the sun. F&V flash units come with a standard flash tube which measures 5600K, and is daylight-balanced for film. We also offer optional UV-coated tubes, rated at 5200K.

Lens Flare: Sometimes ambient light or even flash light is reflected back on to the lens of your camera, this is know as lens flare. Occasionally this effect is desired, but more usually it is unwanted, changing the angle at which you are shooting or the angle of the lights can often solve this, other ways of reducing lens flare or light spill include using barn doors or flags.

Main Light: The main is the primary light used in your lighting set-up usually the brightest in your setup.

Recycle: When flash unit fires, it releases all of the energy stored in the capacitors. Before the unit can be fired again the capacitors must have time to build up enough energy in order to fire again, this is known as recycling. Fast recycle times are important for rapid shooting as you do not need to wait excessively for the power to recharge.