is it possible to get “bokeh balls” using an iPhone camera?

Question

Is it possible to get "bokeh balls" using an iPhone camera? I'm sure there are a lot of apps which allow you to insert fake ones, but I am referring to "real" ones generated using the cameras optical system.

Answer 1

Yes, it is possible - however, a quick experiment shows that it's a little tricky and that the results aren't as good as what you can from a bigger camera.

The bokeh discs are just out of focus lights - so all you have to do is place some lights and "defocus" them.

Here's what you do:

1. You need an iPhone 3GS or later, earlier models are not capable of changing focus and so can't make anything out-of-focus.

2. You need lights, Christmas lights often used for this, you need to place the lights as far away from you as possible (the farther away they are the bigger the bokeh disc) and you need them to be much brighter than the background (that last part is easy, just make sure the background isn't acting like a big reflector directing light into the camera and you'll be fine).

3. You need to focus on an object that is very close to the phone, something like 5-10cm (2-4inch) from the phone, maybe even closer - anything farther and the lights will be in focus - this means your subject has to be quite small to be this close and still not fill the frame (just place your subject in front of the phone and tap on it on the screen to make the phone focus on it)

This will be easier if you can use something to hold the phone (and the subject) since any movement will make the phone refocus and bring the lights back into focus.

Answer 2

If only the question was about all smartphone cameras, this example photo would fit in. But, posting it anyway, to show the size of those bokeh balls instead of trying to describe it by mere words. They are quite small, as you can see. Bright ones are made of several overlapping "balls" but some dim ones appear individual. Actually all background blur is made of these circles, but only those created by a point light come up visible.

Photo taken with a Nokia smartphone. 1/50 sec, focal length 4,7 mm, f/2.8, ISO 79

Click for original size photo.

Answer 3

iPhone 3Gs and laters have the ability called AE/AF Lock (Auto Exposure/Auto Focus Lock) just like on modern DSLRs. Focus on a very close subject by tapping on it on the Camera screen app and hold for 1-2 secs, you will see the focus square pop 3 times and the message AE/AF Lock appear at the bottom of the screen, from now the focus and exposure reading will be locked on the spot that you tapped. Now move the camera to the area you want to snap bokeh and take the photo.

Answer 4

Bokeh is the name for out-of-focus highlight, so its presence is enhanced when the depth of field is shallow (so that you have a lot of the background out of focus) and when there are bright highlights. You could try to focus on an object as close as possible to the phone, with bright spots in the background (typical set up: focus on a flower like if you were doing a macro picture and the light passing through the leaves of the tress in the "distant" background will possibly give rise to bokeh).

This blog post recommends using a macro iPhone lens and provides an example of the results, so that you can appreciate if it's something that could satisfy your needs.