Update: We are giving away 2 of these lenses this week to the lucky winners of our latest contest!

One of the downsides of the iPhone camera is that it is a fixed length lens. There’s no optical zoom – instead, you have to crop on your iPhone or PC/Mac for a zoom effect or use a digital zoom application such as Camera Zoom, with the typical problem of a digital zoom that its use results in degraded image quality.

We recently found some optical lenses for the iPhone, by a company called USBfever. They graciously provided us with a sample of their 2x Tele Zoom. Here are my thoughts about it:

Attaching the lens
It is very simple to “mount” the lens on the iPhone. It comes with two small magnetic rings with self-adhesive tape. Simply glue one of them around the lens of your iPhone and then “snap” the lens (actually, any of their lenses) on the iPhone. The magnet does a good job holding the lens in place. To unmount, pull off the lens, attach the lens cap and bottom. Done!

Using the lens
The lens is made of sturdy aluminum and since it is attached through a magnet, you can slide the lens around on the magnet for optimal coverage. One issue: Since it is round, it heavily vignettes (see screen shot below). There is no way to avoid this – I guess it would have been possible to construct optics to avoid vignetting, but that typically includes multiple lens elements and drives up the cost and weight of the lens. Vignetting can simply be cropped in post processing.

Vignetting very visible with 2x Tele lens

Optical Quality
The quality of the optics is surprisingly good given the low cost of the lens. I did not see any quality degradation. On the contrary, as the comparison image below exemplifies, there’s a lot more detail visible in the 100% crop from the image shot with the 2x telephoto than is in the regular image.

100% crops: The tele lens brings out the details nicely

Cleaning
The lens is small, but can be cleaned easily with swabs or your favorite lens cleaning solution. Personally, I use a LensPen, which works just fine on this lens.

Personally, I prefer optical zooms over digital zooms at any time of the day due to better quality pictures even if it means I have to deal with vignetting. Thus, since the lens is very small and light-weight, I started to carry it around with me in my bag. So far, I’ve used it quite frequently, since it’s so quick and easy to attach it to my iPhone and since I like the quality of the photos that I shot with it.

Verdict: Highly recommended

In addition to the 2x telephoto, USBfever also offers a fish-eye, a 5x tele and a wide-angle lens for the iPhone.

Weight: 6.6 grams, including lens cap and strap

Price: $16.99, directly from USBfever

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