There are many ways to shoot great portraits with speedlights on location – the following tips may prove useful in providing a shortcut to your learning curve.
• Shoot in Manual mode which will allow you to easily balance the ambient light of your surroundings with the light from the Speedlights. If your camera is in manual mode, the exposure settings shown on the camera is for controlling the amount of ambient light recorded
• To achieve high quality images your need to set your ISO to either 100 or 200, and an aperture value which will give you sufficient depth of field to record your subject in sharp focus – F/4 is a good place to start.
• Set the Auto FP function in your camera (if it has it) which will allow you to sync the flash with shutter speeds up to 1/8000th of a second. By moving your shutter speed (higher or lower) you can control how much ambient light is recorded in your image.
• You can use the speedlights in either TTL or Manual mode to light your subject, it is best to try and keep the lighting as simple as possible, and for portraits remember that ideally you want soft light which will be created by a large light source, reasonably close to your subject
Want to learn more? Check out Nikon School's full list of speedlight training courses here.