A Beginner's Guide to Stereoscopic Photography on a Smartphone: Kúla Bebe
Ian Hellström | 23 July 2019 | 3 min read
While you can take great stereoscopic pictures with a smartphone using sequential shots, as I described in the first and second parts of this three-part series on smartphone stereo photography, sometimes you want to capture a three-dimensional scene in motion. Even that’s possible but you do need additional gear, for instance the Kúla Bebe.
The Kúla Bebe is an inexpensive, plastic add-on that you either twist onto a plastic strap that goes across the back of your phone or clip onto the side. It’s an arrangement of mirrors that allows the camera to see two copies of the same scene, slightly apart, at the same time, similarly to how our eyes perceive the world around us. The stereo base is 4.5 cm, so the distance to the nearest object in the scene must be at least 135 cm thanks to the 1:30 rule. Note that the stereo base is shorter than the typical distance between the pupils of adults.
Because the stereo base is fixed, you cannot make hypo- or hyperstereos. The device does give you the ability to take capture scenes in motion in three dimensions, or of course record 3D videos!
The strap is fairly stable, but it requires you to take off any protective case. That’s not necessarily a great option if you use a case to guard your phone against falls.
It would have been helpful if the Kúla Bebe could be screwed into a case such as Lemuro’s, which I have been satisfied with so far, but alas. You can use the clip with a phone case though. As long as you do not mind aligning the mirrors and camera by means of trial and error, it’s all right. With or without phone case, the clip is a bit wobbly in my experience.
There is a free companion app: Kúlascope. When you open it, it looks like this:
You can clearly see rounded borders around each image and that’s because both the mirrors and the non-perfect alignment between the attachment and the phone’s camera cause the edges to be obscured and blurry. You can clearly see that when using a basic photography app:
The edges are dark and wiggly and there is a distinct haziness in the middle of both images. Then again, the same haziness appears in Kúlascope:
The haziness in the middle, which is due to the mirrors as well as any reflections of stray light between the Kúla Bebe and the lens of the camera, as the two do not form a perfect seal.
The app has its own storage, so you can take multiple pictures in quick succession, unlike some stereoscopy apps.
The advantage of having simultaneous images taken with the aid of the Kúla Bebe is clear when we add some motion to the image. For instance, ducks swimming in a pond:
Or a stream of water in winter:
As you can see, the haziness in the middle is limited, so it is possible to use additional equipment, such as the Kúla Bebe, to snap nice stereo pictures of scenes in motion, as long as you avoid stray light and use the Kúlascope app to deal with the edges.
The best camera to shoot pictures with is your smartphone’s, not because it beats a professional DSLR camera (because it really does not!), but because it’s readily available in your pocket (or handbag). When I’m on the road I rarely remember to bring along a fancy DSLR, so I might as well learn how to make the most of my phone’s built-in camera. I hope the series on stereoscopic photography with a smartphone was as enlightening for you as it was fun for me. Good luck!