Today I did a small test with the iPhone 5S. I wanted to see how good is the LED light luminosity when shooting a video in an almost completely dark room. The iPhone 5S has a dual LED flash. When you shoot video, both LEDs are being used to provide the strongest illumination for your subject. Unlike in stills shooting, the LED lights are lit continuously and not in bursts.
You can see the the user interface is different before and after you press the big circular red record button. Before you shoot the video you have the option to focus on your subject or use the AE/AF lock. You also have the option to turn the LED flash On or Off. After pressing the record button, you get to see the video recording timer, a Stop button to stop the video and a white circle button to capture stills while shooting videos.
I was shooting in an almost completely dark room. When the LED was off I saw a black screen on the viewfinder. I turned on the LED constant video light by pressing the “Off” text near the Flash icon.
Two of the dual LED lights were active and provide pretty good illumination for closeup shots, but it couldn’t properly lit up the subject from over one meter (3.2 ft.) away. The illumination coverage also depends on the color of the subject and its surroundings. A white wall will reflect more light compare to a dark color. I was shooting the subject against a white wall, and the illumination was still relatively weak.
I’m sure that the iPhone 5S provides pretty strong illumination compare to single LED flash, but it’s still relatively weak. It’s always preferable to shoot videos in a well lit environment, whether the source of the light is natural or artificial. This will also force the camera to shoot in lower ISO sensitivity instead of high ISO, which will also reduce the amount of image noise in the video.
In the iPhone 5S sample video below I tested the power of the dual LED flash when shooting video. I turned on the video flash on and slowly start moving away from the subject. You can see that after approximately 1 meter it’s hard to see the subject. The iPhone 5S LEDs can also be used as fill in light as well, regardless of the amount of ambient light in the scene. However the light is very dazzling and I’m pretty sure that people wouldn’t like that light pointing straight into their eyes and your cat will hate it too, trust me 🙂
http://www.youtube.com/watch?v=njqSfnOEe2s
I shoot most of my videos where is enough ambient light and don’t use the LED flash for video. I just wanted to share those findings with you so you can be aware of the pros and cons of using the LED flash in video recording.