Clicking photos using the natural light could be fun and challenging, but then there are situations when introducing a flash light becomes a necessity. What if you are doing a fashion shoot outdoors and the background of your frame is bright and properly exposed, but your subject is getting underexposed? What if you wish to create a rim light effect on the hair of the model using the natural light but end up getting underexposed face? What if you find a beautiful location and want to frame your photo there, but the natural light is really dim?
There could me multiple situations when using a flash light would result in better quality results, out of which few have been mentioned above. In order to get started with flash photography, you must be aware of some steps that needs to be followed in order to get the best out of your flash light.
Set exposure as per your background
First things first, you need to expose for the background. This is done by pointing your camera towards the background, making sure that the center point of the frame is pointed towards the brightest part of the background. This will give you exposure reading which you need to note and then set the same values in your camera by switching to manual mode.
You will have to repeat this process when the background light changes, or you can adjust the setting as per your experience and requirements.
Position the flash as per your requirement
To get started with the lighting setup, first you need to visualize and decide the quality and direction of light that you want to achieve. Quality of light means whether you wish to use soft light which is achieved using large light modifier, or hard light which can be achieved by using bare flash or a smaller light modifier placed at a distance.
The next thing is to decide on the direction of the light that you want to achieve on your subject and then accordingly place your flash. If you wish to create a moody or dramatic photo then you will be using side or back lighting, and if you wish to click beauty shot then you would be placing your flash on your camera.
Set the flash mode and exposure
Depending on the flash make and model that you own, you would need to choose the flash mode to proceed. You can either use the manual mode or the TTL mode (if you are using a TTL enabled flash such as Canon Speedlite 430EX III-RT Flash and Godox TT685). In the manual mode it is you the photographer who controls the flash light exposure, it has nothing to do with the camera exposure settings or the available light.
Depending upon the ambient light or as per your requirement you can adjust the intensity of flash light. the flash light at 1/1 reading throws the light at full intensity, in order to reduce the intensity you can change the reading to 1/2, 1/4, 1/8 and so on. As you move from 1/1 to 1/2 the intensity of flash light gets half, and if you move from 1/1 to 1/4 it reduces 4 times, and it goes so on. It all depends on what light effect you want to create and then you can set the flash output value accordingly.
The TTL mode is also know as through-the-lens mode as it evaluates the light coming through the lens and then sets the light intensity accordingly. This is exactly how the automatic made of your DSLR camera works, examines the light coming through the lens and then sets the exposure settings accordingly. Sometimes you might not be pleased with the output that you are getting using the TTL mode, you can use the FEC (flash exposure compensation) feature in this mode to increase or decrease the light intensity on the scale of -3 to +3.
NOTE: You can also control the flash exposure by adjusting the aperture value. The smaller the aperture value the more the light would be recorded on the image sensor, and the brighter the final image would appear. Similarly, the higher the aperture number the less the light would enter the camera, and the darker the final image would appear.
Take some test shots, zoom, and then proceed
When ever you setup a new lighting arrangement or are about to start with your shoot using a/multiple flash, always take a test shot and examine it. Zoom in to the image and check if the desired lighting effect is being achieved by the flash light arrangement that you have made, if not then work on it until you get the required result.
Because if you fail to do so, you might go home and then realize that you failed to achieve the lighting that you had thought of. This practice will also help the model to concentrate more on the posing, instead of waiting for the lighting to be adjusted in between the shoot.