For photography of small plants, animals and fresh water creatures, there is a need for an intermediate level of magnification between a high camera macro setting (2-4X) and the lowest power available on the microscope (20-40X). Furthermore, it is desirable if high-level macrophotography can be portable: traveling to the flower or the glass of the aquarium rather than the flowers and water critters going to the magnifier.
This gap can be filled by a simple, intermediate-power cell phone magnifier constructed from a microscope lens, a piece of flooring, and a few rubber bands. The lens is a 4X, infinity-corrected Nikon 4X wide-field objective. The mount is a portion of 3/8″ high density fiberboard (HDF) flooring, desirable for its flatness, hardness, and ability to be worked with simple tools. The field of view of a microscope objective lens is small, but this particular lens works well with the very small, high resolution sensor on the cell phone.
On a drill press, the flooring, which is thicker than the length of the objective threads, is drilled approximately half way though with a 1″ wood bit to create a recessed hole for the objective. The remaining thickness of HDF should be equivalent to the length of the objective threads. The latter is then drilled the rest of the way using a bit just slightly smaller than the objective threads. This smaller opening can be carefully rasped and sanded out, maintaining the circular shape, until the objective can be threaded in with gentle pressure, Doing this with a fine circular rasp bit or small sanding drum on the drill press while the mounting plate is moved on the press table will maintain the vertical edges of the hole.The brass threads on the objective, being harder than the fiberboard, will create their own threads in the wall of the mounting hole. The base of the objective should end up flush with the back side of the mounting board. The whole piece is then given a rubbed, wax finish with Briwax or a similar one-step finishing wax. Since the magnifier is intended for use outdoors or around aquaria and ponds, this finish soaks into the porous edges and protects them from moisture.
The phone is then held onto the back of the mounting plate with two broad, sturdy rubber bands; I use the ones that hold stalks of broccoli together in the supermarket. If you don’t like broccoli, steal a couple next time you are in the produce aisle.
(Sangunis: Stealing the broccoli itself is shoplifting and will land you in jail, which is a nasty place full of the kind of vertebrates and invertebrates who are NOT quality company. However, stealing the rubber bands, since they are technically part of the packaging, lands in a gray area according to two-footed legalities and will just get you thought to be a bit weird and to be avoided. If you are an old vertebrate, just drool a bit and they will gently escort you outside, hand you a glass of water, and have someone drive you and the rubber bands home. This is the perfect ending to a minor heist.)
On the Samsung Galaxy 4, dial up the magnification to 4X. The image from the objective should almost fully fill the screen with a bit of vignetting at the edge. Focus by moving the whole assembly backwards and forwards through the optimum working distance of the objective, about 1.5 cm. The autofocus on the phone will take care of fine focus, or this function may be turned off. If the phone tends to slip and lose its centering, glue a narrow (~3 mm) strip if thin rubber or leather on either side of the back of the mounting plate to help hold it in place.
This method works well with the Nikon objective ($65 on eBay), which has a flat field and good resolution. There are probably many other objectives, such as the Zeiss Jenas, Tiyoda Planachromats, Polish PZO lenses and even older American Optical 4X infinity-corrected lenses, which may work and are available even more cheaply.
For aquarium pond life photography, the longer working distance of this magnifier/cell phone camera combination allows it to be placed against the aquarium glass, accessing objects within about 1 cm of the inner wall of the aquarium. From this vantage point, still images or videos can readily be taken. The greatest problem arises from trying to hold the assembly steady, especially when pursuing a moving organism. A detachable tripod mounting angle bracket can be added easily. For handheld videos, YouTube has added image stabilization software to its editing package, and this helps greatly in making presentable videos of small moving organisms such as these graceful, bottom-dwelling oligochaete worms:
For still images, the addition of a tripod bracket and focusing rail might also allow stacking of images for non-moving subjects if the autofocus function of the cell phone can be turned off.
A hand-help, portable cell phone magnifier of this power also makes possible new levels of photographic interpretation and creativity. Consider this 10X image of flower petals:and this similar shot of stamens, tweaked with maximum Vibrance and manipulated color balance in Curves:
The possibilities are endless – put your phone and magnifier in your pocket, and go out and explore the world of the very small. You can do it in your garden, on a walk, in the produce or flower department at the supermarket, in an aquarium, or at your local nursery. Create!