If you do not want a full silhouette photo you can just give a slight fill of flash to get detail in your subject.
As we all know the best time of day to take those stunning images is early in the mornings and late in the afternoon .There is nothing that beats that golden glow and that sparkle in the eyes that is created by the sun sitting at a low angle. The problem however is that the best photo taking time doesn’t last long and the opportunities to take those good shots doesn’t always happen at the best lighting time.
So what do we do if we are on a great trip and see the best sightings but its way past “best time” or the subject is in the shade or the sun is behind the subject?
Well the simple answer is to illuminate your subject with the flash gun. The complicated part of it, and it is not really that complicated, is to use your flash in such a way that you don’t get flat and overexposed photos.
Often when the sun moves in behind the clouds or a subject is in the shade you get those flat almost bluish looking photos. To correct that dull look and to get a nice sparkle in the eye is all you need to pep up the photo a little bit and that you can do with fill in flash.
Fill-in flash is also a wonderful technique to illuminate the subject in such a way to reduce contrast and to fill in those unwanted shadows.
The most modern flashes employs TTL technology which means the light reflecting off the subject from the flash is measured through the lens by a sensor in the camera. This makes for rather effortless fill flash photography. The key here is to do some test shots and to see how much one need to compensate in various situations. Most flashes have a compensation setting and a lot off modern cameras has a compensation factor that can be set from the camera’s body. I often set my flash to minus 1 up to minus 2 stops. I must admit working with digital is a great help in this regard. I take a quick test shot and compensate accordingly.
A great advantage of using flash during the day is also to get an increase in depth of field in lower light situations such as a bird at close range and perched in the shade of the tree.
More than often when you photograph a small bird at close range with a longer telephoto lens you would notice that you have limited depth of field and often you have to close your aperture to f11 or even smaller. With the use of flash you can generate more light so that you can close down on your aperture.
Many flashes have zoom heads and they read their zoom distance from the lens that is employed at that stage. Most flashes’ zoom range is between 24 mm and 70 mm and will have a good coverage indoors but really fair to poor outside where there is a light fall-off. The angle of the projection also becomes a real problem when you use a longer lens.
Let’s look at an example using a Canon 550 flash and an ISO setting of 100 ASA.
This flash has a Guide Number of 55 and when you use it at the flash’s zoom setting of 24 mm it has a effective GN of 28 and will cover up to 5 meter at f 5.6 (28 divided by 5.6).
When used at 70mm it will have a reach of approximately 9.8 meters .That is derived from GN 55 divided by 5.6.
So as you can see even with a rather strong flash your reach is very limited and that at rather wide apertures as well.
The angle of view of your telephoto lenses also decrease from approx 20 degrees on a 100 mm lens to around 3 degrees on a 600 mm lens.
Typical nature and bird photography often happens with lenses of 300 mm and longer.
So you can see that the flash coverage is far from sufficient since your flash that is zoomed to 70 mm gives a far wider coverage and lot of light and flash energy fall wasted beyond the narrower point of view of the longer lens.
To solve this problem a Flash Extender should be used. It is a simple but effective accessory that slips onto your existing flash and narrows the beam to fit the angle of view of lenses 300mm and longer.
This was taken in my garden to illustrate.
This first image was taken with a 600mm f4 lens and without the flash extender.
IN the second image I used the flash extender to fill the shadows under the nesT.
So what exactly are the advantages to using such a device? First, by narrowing the beam, the effective guide number of the flash is increased. This means that the flash, at a given output will travel a greater distance and thus will need less power to light its original maximum distance. From our example above, the original maximum distance was 9.8 meters at f5.6. If we double the G.N., for the same energy, we can then shoot 20meters at f5.6 (or 10meters at f5.6 with the flash not working as hard) (or even increase or depth of field on shorter distances)
The same flash discussed above and will give about 100 full power flashes and take as long as 13 seconds to recharge with a new set of batteries. If you consider the impact of our flash not having to work as hard if we use the X-tender, we can increase the amount of flashes per set of batteries and decrease the recycle time between flashes.
So it makes perfect sense to have a light and effective accessory that you can use to make your flash photography easy.
This accessory is not manufactured by the flash makers except for Metz which makes a flash extender for certain of their models.
We at OutdoorPhoto have gone to great length s to source the product that is used world wide by all the wildlife photographers. The Flash X-tender also known as the Better-Beamer is an affordable and easy to use extender and it is available in different models to fit various flashes.
It has a compact design to fold up and fit into your pocket or gadget bag. It is quick and easy to fit and give outstanding results with a 2 to 3 stops gain in light.
Should have any interest in this product you can call us at 012-348 3693 or get it from our Outdoorphoto shop here.
By Hedrus van der Merwe
All images © Hedrus van der Merwe
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