The just released ExoLens kit for the iPhone 6 (iPhone 6 Plus in May, 2015) is a professional pair of lenses, 3x telephoto and wide angle that attach to the iPhone 6 with a sturdy lattice mount. The mount is threaded with a standard 1/4"-20 connection, ready for a tripod. The system is designed for growth.
While the iPhone has been growing in size slightly, it remains rather modest in size compared to a DSLR. That means there's a practical, sensible limit to how big a lens we really want to hang on it. That said, the rear facing camera in the iPhone 6 is excellent, and we're far from pushing the limits on how large an accessory lens could be attached in order to achieve better results.
More glass means more design freedom, but that also entails extra cost. However, with a suitable mount, ready for a tripod, the ExoLens kit could well replace a DSLR under certain conditions. I asked for more details about these rather large lenses:
With the quality of the current iPhone 6 and 6 Plus cameras it didn't make sense to focus on miniaturizing the lenses as Olloclip has. Instead we concentrated on quality and a greater line of options. For the current lenses the size allowed us to go higher power on the lenses without suffering vignetting. Additionally, the larger diameter telephoto allows more light into the image sensor than a miniaturized lens. Lastly, the larger format will allow us greater flexibility as we move forward with even more complex lens units this year.
As these additional lenses, in development, are released, I hope to review them as well.
Currently, there are two interchangeable lenses in this kit that screw onto the aluminum mount. The first is a 3x telephoto (with an effective focal length of 90 mm). included is a threaded, removable lens hood. The second is a 165 degree wide angle lens. Each comes with full lens caps for both ends.
Not sold by ExoLens, the Square Jellyfish tripod is fairly inexpensive.
The aluminium mount slides onto the iPhone 6 until the lenses line up. There's a soft material inside the mount so the iPhone doesn't get scratched. From there, you can hand hold or mount the frame on a tripod. There's an opening for the iPhone's on/off button, but the frame covers the iPhone's flash. I asked the developers about the lattice design, and they wrote:
As iPhones get thinner and lighter, mounting a large quality lens begins to throw the (in hand) balance off. We designed ExoLens to mount via a rigid aluminum bracket that spreads the mass of the lens system over the device for more stable shooting. Additionally the bracket has upper edges to aid in grip and the tripod mount is located as a reference point for the shutter button (volume buttons). The overall shape of ExoLens was a result of these features combined with the goal of a light and rigid structure. We find the end result has a certain industrial beauty that we feel compliments the design of the iPhone.
Included is a microfiber carry pouch. I found that by placing the lenses face to face, then dropping in the lens hood around the base of one lens, it all fits nicely for travel.
Next page: The optical details and sample photos.
Page 2 - The Optical Details and Sample Photos
This is a quick-look review, and so a detailed optical analysis or critical optical comparison to competitors is beyond its scope. However, having been an amateur astronomer all my life, I can affirm that when I look at these lenses, I see a considerable amount of capability. Larger lenses offer possibilities that smaller lenses can't achieve, just as an inexpensive telescope eyepiece with tiny lenses cannot achieve what the extraordinary Televue eyepieces can.
I inquired with the developer about lens coatings, always a subject of interest to me. Lens coatings, often a quarter wavelength of magnesium fluoride, reduce reflections. There are even more expensive multi-layer dielectric coatings used on high end optics. How many of the lens surfaces are coated determines the overall light transmission. However, I did not hear from the developer in time for this review. When and if I do, I'll update this article.
Here's a closeup I took of the telephoto lens, with hood attached, along with the developer's internal diagram.
Similarly, here's a closeup of the wide angle lens along with the developer's internal diagram.
As I said above, I'll leave it to advanced optics labs to look into the details of edge sharpness, distortion, and other aberrations. For the purposes of this quick-look, I'll simply show what can be done with the two lenses.
Here's a shot from my front porch of the neighbor's house across the street with just the iPhone 6 camera.
Here's the same shot using the 3x telephoto. One can see a slight loss of sharpness on the far right side (the mail box), but any lens system is going to have that at the extreme edges. I judged the image, overall, very good.
Next, here's a standard iPhone 6 photo of part of my workspace.
And here's the same view with the 165 degree wide angle lens.
Packaging & Documentation
The box is well designed and has a flap that opens to provide more product information. Included inside a small piece of paper with warranty information (one year) and contact information. Regrettably, the desire to save a bit of money results in labelling in multiple languages—which is a bit distracting. The slip of paper shows how to properly slide the mount onto the iPhone, and one should pay attention to that the first time.
I was impressed with the thoughtfulness of the design as well as the potential for future, possibly even larger lenses, to achieve new levels of optical performance. The packaging, fit and and finish of the lenses and threads is first-rate. While this system costs quite a bit more than the best-known competition, the possibilities for professionals and advanced amateurs appears much greater.
A version for the iPhone 6 Plus is planned for release in May 2015, but the exact date and pricing has not been set as of this writing.