Macro photography with a cellphone
Writing this article was actually a bit unplanned. As soon as I picked up one of the macro + wide-angle phone lenses—bought at work for a totally different purpose—to test it, I could already “see” this piece titled “Macro with a cellphone.”
Since this article was written in 2013, it reflects the technology of that time. With a modern phone you’ll get much higher image quality. I should make time to update the whole piece.
While people poke fun at many compact, SLR-like, even DSLR camera models for having “lentil-sized sensors,” a phone sensor measuring 4.5 mm × 3.4 mm (iPhone 4) gave me zero hope for macro. On top of that I couldn’t shoot RAW. But that’s fine—my goal isn’t to create a new macro rig for myself; it’s just to see what’s possible and share it with you.
A macro lens for the cellphone
The lens is a tiny little thing. It has to be, since it sits over the phone’s camera. It’s a not-so-great model found on eBay for a few dollars. You get two lenses together—wide-angle and macro—stacked one on top of the other.
The lens has no bayonet mount. Instead there’s a circular magnet wrapped around that side. The bit that looks like metal is actually a magnet. So we need to “stick” the lens over the phone’s camera using the magnet.
I said the lens has two parts. They’re screwed together. You unscrew them and use only the part labeled MACRO. Wide angle is not our topic. To give a sense of size, here it is next to a 1 TRY coin.
There are cases sold that let you use these lenses with a phone. You slide the phone in, there’s a window at the camera, and a mount for the external lens. But my sample didn’t come with a case. I had to make my own case that could incorporate the magnet.
Macro photos with an iPhone 4S
Laid out on the table, the kit looks like this. We’ll do fine focusing with a Newport Linear Stage. For lighting we’ve got an IKEA Jansjö LED lamp—very popular for macro thanks to its warm light. We made a cardboard sleeve for the lens out of a pill box. To give the lens something to grab onto, we glued two tiny metal pieces to the cardboard. In the background, our live weevil is freshening up on a leaf held by clips before the shoot.
With the cardboard sleeve mounted, we placed the phone on the Newport. It sits a bit wobbly, so pressing the shutter will be an issue. Unlike a DSLR, I don’t have a remote for the phone. A tiny touch—and wobble—will accompany the exposure. That will likely show up as a loss in quality.
Once focus is locked, we can use the Newport micrometer to focus precisely where we want.
After the first try above, I didn’t like the harsh reflections, hard shadows, and edgy bokeh, so I placed a layer of white tissue between the light and the bug. The tissue acts as a diffuser to soften the light.
Macro again, this time with an iPhone 4 I wanted to repeat the test another day—this time with an iPhone 4 instead of a 4S. The cameras differ: the 4S is more advanced. Let’s see what the 4 can do.
Today’s subject is a dead hornet. Found it in the yard. For some reason I keep coming across dead bees these days—mostly honeybees. It’s like they’ve rained down from the sky. Sad…
I started with something I skipped in the first test: I shot with the phone’s bare camera first. To see what the add-on lens gives us, we should first see how far we can go without it, right?
No one would call this macro. Even at the closest focusing distance, you can’t make out much beyond the species. Let’s rebuild the rig and move in:
The result isn’t bad—I can comfortably call this macro. You can see plenty of detail, including a big strand of lint on it. But I still hadn’t figured out lighting. Despite using a paper diffuser, blown highlights crushed details and are distracting. If only I could have shot RAW.
With the iPhone + macro lens combo we can focus at 1 cm. These examples were taken that way. Because the phone and bug are so close, lighting is a major headache. Another downside of the short working distance is perspective distortion in focus stacking. That makes keeping framing consistent in burst sequences difficult.
Macro video with a cellphone Yes, video… I found the most fun part of macro with a phone to be video. While the photos are far from satisfying me, video—by nature working at lower resolutions—doesn’t make the quality loss as obvious. As a very portable macro-video solution, the iPhone + macro lens combo can record our favorite critters’ behavior quite successfully.
1080p Full HD handles it nicely.
You can watch my first test—the weevil’s grooming/itching behavior—on YouTube. During the shoot I move the focus distance back and forth with the Newport, which also gives you an idea of its precision. I recommend 1080p and full screen.
http://www.youtube.com/watch?v=5stdTJ7Hfgs
Magnification and distortion After seeing the practical results, I measured magnification and distortion using graph paper. As you can see in this photo, the lens’s distortion is brutal. This is a big no-no for macro lenses—here it makes the paper look like it’s melting and running.
There’s also a non-planar focus, which—beyond edge distortion—creates out-of-focus areas. Ignore the darkening at the top left—that’s on me; I didn’t get light in there.
If I measure in pixels per millimeter, I can compare magnification to a 1:1 macro lens. By that logic, the iPhone + macro lens gives us about 0.8×—quite close to 1:1. But if we compare working distances, a real macro lens gives us about a hand’s span, while the phone forces us to make do with 1 cm.
Conclusion Although I find it lacking for stills, it would be unfair to say “forget photography.” The results aren’t that bad. I can also recommend it to those who don’t own a camera but are curious what macro shooting is like. But I can’t say it’ll be easy.
On the flip side, getting a very enjoyable video solution for $2.5 is great. I think I’ll keep using it for macro video. While DSLRs are better at video, I won’t always want to drain their precious batteries—my phone can come to the rescue.
During processing the phone heats up and the battery drains quickly. Keep an eye on the charger while shooting.
