Lesson 33: How Far Can You Flash?

In the past couple of lessons, we’ve been talking about how to deal with moving subjects with an iPhone camera.  I showed you how to use the flash both in the traditional “flash” mode and in the flashlight mode in Lesson 31.  I made the comment that the iPhone (4S) flash will do you no good from distances more than 5 feet.

Afterwards, I suffered from guilt because I haven’t actually measured when the LED light that passes for a flash actually ceases to be effective.  So, today, I thought I would rectify that.

I set a glass with flowers in it at one foot intervals and took a photo with the flash set to on using Camera Awesome.  There is no difference in the effectiveness of the flash based on the app you use, so this is app independent.  However, I also wanted to test whether the exposure was any better using the flashlight mode versus the “flash” mode just to see if the app compensates for the extra light of the flash or not.

So, here is what I discovered:

At one foot away, the flash caused over exposure and “hot” spots.  As you can see, the effect gets better as the subject gets further back from the phone until you get to about 5 ft.  Then, the subject falls outside the circle of light cast on the floor.  However, notice that the shadows in the background all the way back to the door (at 10′ 6″) are lighter with the flash.

This is good information–while the flash may not be good for lighting a subject at more than 5′ away, it can be used to cast light into shadowy areas up to 11′ away.  Also notice the bright circle on the floor and how distracting it becomes when the subject is outside of that circle.  Raising the phone up and away from flat surfaces will help to reduce this effect.

As for whether the flashlight vs flash setting work better, well, let’s try some side-by-side comparisons.  Here is the flower vase side-by-side with the flash setting versus the flashlight setting (at 3 feet):

As you can see, the exposure looks more even with the flashlight setting than with the flash–the circle of light on the floor is far less pronounced.  So, unless you want a more pronounced circle of light, if you have enough battery life to turn the flashlight on, do it.  However, bear in mind that the flashlight setting consumes more battery life because the light is on longer.

Your Assignment:  Try using the flash at various distances in different lighting.  The flash will make a more noticeable difference in near-dark situations than it will in well-lit scenes.  It’s often enough light to get a photo in a totally dark room if you’re in range.  Also, using the flashlight setting will help the camera find focus when the scene is very dark.  Make sure you have a fully charged battery!

Do you like the flash or flashlight setting better?  If the answer is “it depends,” what are the circumstances where the flashlight setting helps the most?