The following example demonstrates a simple method for calculating the equivalent focal length by multiplying the standard 1x lens focal length of a smartphone by the magnification of a telescope. For instance, the iPhone 15 Pro offers three focal lengths—24mm, 28mm, and 35mm—through its 1x lens. When paired with an 8x binocular, the equivalent focal lengths become 192mm, 224mm, and 280mm, respectively.
The SR BC APO series binoculars not only deliver exceptional visual performance, but they also make it easy to capture high-quality images with a smartphone. Sky Rover Optics’ newly released smartphone adapter, designed specifically for the BC APO series binoculars, unlocks endless possibilities for long-range photography. Unlike the common clamp-style mounts on the market, this adapter uses threaded connections on both ends, offering more stability and better alignment. This design minimizes stray light interference, resulting in clearer images with richer colors.
While developing the adapter, a local group of nature enthusiasts was planning a trip to Africa, so we provided them with several prototypes to test. Despite having little experience with binoculars or afocal photography, they quickly mastered the setup within minutes and achieved impressive results, demonstrating the ease of use and reliability of the adapter.
With just a smartphone and a binoculars, the overall setup is lighter and more compact. Although the resulting images may not rival those from professional cameras (which are, of course, larger and heavier), the ability to observe distant objects and capture them on film is an exciting experience that’s both rewarding and convenient.
Photo by Renfei
Shooting Equipments: SR BC 10x42APO/BC 10x50APO binoculars+ smartphone adapter+iPhone 13
HOW TO USE SMARTPHONE ADAPTER
1. Install the smartphone adapter
2. Connected to the binoculars
3. Adjust the image edge quality
1. You can change the distance between the smartphone and the eyepiece by loosening the locking adjustment ring and rotating the smartphone adapter barrel. Adjust the image clarity at the edges of the field of view when taking photos with your phone. The standard should be that there is no noticeable blurring at the edges of the field of view around the image.
2. Open the camera app on your phone. It is recommended to start with the 1x (standard) lens. After achieving a clear focus, you can switch to a different magnification based on your needs.
4. Focus adjustment
Once the field of view is clear, you can use the binoculars' focus wheel to adjust the focus (clockwise or counterclockwise).
