Article prepared by Ottawa/Kanata Professional Photographer Jeff Ryan, Ryan Studio
CORRECT FLASH SYNC/SHUTTER SPEED
Continuing our discussion of electronic flash equipment, the reader should be aware of the necessity in synchronizing their “camera’s shutter speed” correctly when using electronic flash. If your camera is fully automated as are many in today’s age of sophisticated electronics, you will not have to be concerned with this. However, on camera’s that are not fully automated, this is a very important step that one cannot overlook. Improper exposures, (particularly when using higher shutter speeds) will occur if you mistakenly set an incorrect shutter speed on your camera that does not operate correctly when using your flash. Specifically, many camera’s have a shutter speed dial/liquid crystal display screen situated on top of the camera. One must look for a “coloured number” or a number with a symbol resembling a bent/broken arrow beside it which indicates the correct speed to set your camera at ensuring successful exposures. Camera’s shutter curtains are designed to operate at varying speeds when using flash and this varies depending upon each manufacturer. Often, these coloured dial numbers will range from a 60th of a second to a 250th of a second, and it is within this range of shutter speeds, that you must adhere to for flash photography. What will occur if you accidentally use a shutter speed “higher” than the correct shutter indicated for your camera, is a cropped image and/ or typically underexposure.
Students have produced many images to me over the years and commonly speaking, fifty percent of their 4 x 6” proof prints taken with flash contain little to no image at all. One side of the print will appear to be completely black while the other side of the print will contain a well exposed image. This effect occurs when the shutter speed of your camera is set too high and cannot sync correctly when your electronic flash is tripped. (Too high meaning, if your camera’s shutter speed coloured/arrowed dial indicates a correct setting of a 60th of a second, the user has accidentally dialled in a 125th of a second. Or, perhaps when viewing prints from the lab you are only able to recognize approximately ¼ of your proof print containing any image at all. This occurred because the shutter speed dial was set at a 250th of a second throwing the shutter curtain/flash sync speed completely out of order). On many camera’s the shutter speed curtain of various products travels either from one side to the other or up and down when an exposure is created. The shutter curtain must be given enough time to “open and close fully” while the exposure is being made. Rectifying the problem of prematurely cropped imagery is a simple matter of reducing the shutter speed on your camera to the correct settings as mentioned previously. The reader should be made aware that if you elect to set your shutter speed dial to a speed “slower” than the correct one indicated on your camera, will not harm your finished photographs. Generally speaking, you will receive excellent exposed prints from your lab however when photographing interiors, the lighting itself will have a tendency to appear more yellow/orange depending upon the environment. Well versed photographer’s often intentionally use shutter speed settings on their camera’s, “slower” than the one indicated as deemed correct to allow the background area of the room they are photographing in to become more visible to the viewer. This requires an explanation which I will address at this time directly below.
ALTERING THE SHUTTER SPEED SETTING OF YOUR CAMERA WHEN USING ELECTRONIC FLASH—(DRAG THE SHUTTER)
As a professional photographer, I have been situated in an extensive amount of interiors varying in size, shape and overall design. Each rooms level of ambiance pertaining to available existing light varies considerably depending upon the amount of windows allowing daylight to enter, plus the lighting characteristics of artificial illumination as well. The reader should be informed that electronic flashes can only cover a limited amount of distance when they are fired. In a general sense, your portable flash mounted on your camera is capable of extending light for approximately 20 feet from it or less. This is often confusing for novice photographer’s to grasp because they believe that their flash contains enough power to light up their entire surroundings which is a falsehood. This can be difficult to comprehend for many when consulting the exposure scale of their flash unit when it indicates it will throw light up to approximately 60 feet or more. The typical camera flash contains a limited power supply of 4 “AA” batteries and could never produce light levels accurately enough to cover a considerable distance that one often expects of it. This is when slowing the shutter speed of your camera down while creating flash exposures is extremely beneficial. For example: Let’s assume that you are at a social gathering in an average sized living room or banquet hall and are using your electronic flash as your main light. The people you are photographing are standing approximately 10 feet from you. When you set your flash to the correct setting to illuminate a distance of 10 feet, the light level from your flash drops very quickly afterwards, (behind the people) leaving background areas dark in appearance. My Nikon camera flash syncs at a shutter speed of 1 250th of a second. By slowing the shutter speed on your camera down to roughly a 30th of a second, you are now permitting your digital product or film camera to record approximately four times more light level in the background than it otherwise would not have recognized before. This slowing of the shutter speed will increase the visibility of the background image producing a more pleasing, blending of your subjects, and the background itself. All one has to remember is that while the camera’s movements pertaining to the shutter have been slowed, a steady hand is necessary while tripping the shutter of your camera. This technique has proved itself repeatedly as being very successful particularly when I have had to record large rooms and people in commercial photographic applications. Experiment with this procedure and you will recognize significant improvements in background light levels when using your flash.
Lastly, in many instances, several of my students dealing in the amateur market over numerous years have indicated that too much technical information is required to create flash photography. This permeated new levels of design from manufacturers making the camera systems operate on a higher level of automation. Often in today’s times (2017), novice photographer’s simply have to install an electronic flash unit on their camera, turn it on, and it will automatically synchronize all necessary settings for the user, ensuring the best possible exposures depending upon the scene they are recording. While it sounds like a perfect system it often is not, but with today’s computer sensors in both digital camera’s and electronic flashes, one’s level of success has been elevated to greater heights of predictability.
With Good Wishes,
Jeff Ryan Photography/Ryan Studio, Ottawa, Ontario 2017