Fill flash for wildlife photography
I have had several people ask me about how to use flash recently especially when photographing birds. I had been think of writing a blog for my website so I decided to write about using flash for bird photography. This is based on what I have learned from some amazing photographers, online research and my own experience.
The goal is to not produce a 200 page document and to keep it concise and simple. To give people a starting point. Flash can be used in a variety of ways, as fill flash, as the main light ( I love that , hopefully i will talk about it one day). Multiple vs single flash setups. the list goes on and on.
Well first when not to use flash. When light is great at dusk or dawn, try not to use flash for the most part. Unless you want to photograph a bird that is back light and the goal is not to capture a silhouette. When your subject is in great light and the back ground is in the shade it is best to avoid using flash. Just expose for the subject and this will likely render the back ground completely dark making for some nice dramatic image. ( red shoulder hawk)
Flash can add some nice sparkle to the eyes, it can fill shadows, add vibrance, give it a pop, Freeze motion, balance exposure and make it more even, allows us to shoot in dark places with certain limitations, create surreal dramatic images.
Two basic modes are manual mode and exposure compensation mode otherwise known as TTL (Various brands name it differently).
Manual flash is when the light is fixed as determined by us. Full power is usually 1/1 and as you decrease to 1/2 , 1/4. 1/8, 1/16 etc you decrease exposure by 1 stop for the most part. If your subject moves it is not easy to measure the correct flash out put due to light fall off and the chances are you will miss the shot and the bird will fly away. Camera exposure settings have no affect on the flash out put. So use Manual mode when the subject is static and not moving for e.g birds on a feeder set up.
The other is the automatic mode also know as the TTL mode. Nikon has several forms of this automatic mode and to me one does not given you significant advantage over the other. In TTL mode the camera sends a brief pulse called the pre flash, this is bounced back and the camera’s metering system calculates it and the distance and the right amount of flash is send out to properly expose the scene. Camera exposure settings do have an affect on the flash out put. This can obviously be controlled by flash exposure compensation. The pre flash can spook birds at times and the power can be reduced compared to manual flash. Since most birds are bouncing around and if you want to photograph them as they bounce around the forest it is best to use a TTL/automatic mode.
How to set up flash. There is always some ambient light when photographing during the day time (after all that is the time when we photograph most birds). When you add flash into the mix you are now working with two light sources the ambient light and the flash. So think of this as two separate exposure. One has to set exposure for both of these lights. First and foremost expose for the back ground. You want a darker back ground under expose, if a brighter back ground over expose. Then use the flash to expose the bird or the foreground. If the subject is lit and the back ground is in the shade than I would say don’t bother using flash.
To recap when setting up flash when you are first starting out, set exposure for ambient light. Do not be afraid of using slow shutter speeds. If you leave the back ground under exposed in a forest environment and use TTL flash the likelihood is that the flash will be increased resulting in a washed out bird with blown out highlights with a black back ground. On the contrary if you expose properly for the ambient light the small amount of fill flash can lead to that extra sharpness. One may be able to negate this to a certain degree with exposure compensation for the flash but it has it’s limitations. When using manual flash this is not an issue. hermit thrush image
How do you know what is the right amount of fill flash. It should give a little sparkle in the eye, fill but still preserve shadows, makes the plumage pop and sharp. Its not hard to see an over utilized flash.
I always leave high speed sync on
You will need a flash extender with an extension post ( Off camera flash works best)
An off camera TTL cord for your brand
A better beamer
Last but not the least is the Tripod that can support all this equipment
An External Battery pack to help recharge the flash faster and keep a higher frame rate.
TO recap
I would use manual mode for static subject/constant light and TTL for moving targets/ changing light
Set exposure for the back ground in camera without flash turned on. Once you have set exposure for the back ground turn on the flash and start at Negative 2 exposure if in TTL more. For manual it all depends how far the subject is ( Normally for birds 1/4-1/16 power is adequate to start) and adjust from there.
As a good friend of mine Josh Gallicki says there is front light, back light, side light and then there is flash light.