One of the biggest reasons consumers opt for the 5.5-inch iPhone 7 Plus over the 4.7-inch model is the dual-camera system in the Plus version. It captures photos using the wide-angle and telephoto lens, and Apple’s software merges them to give the best possible outcome. However, Apple might have never told you that the iPhone 7 Plus doesn’t always make use of the telephoto lens.
iPhone 7 Plus telephoto lens doesn’t work in low-light conditions
According to YouTube channel Mac4Ever, sometimes users take a 2x optically zoomed in photo believing that it was a telephoto lens job. But it was just the wide-angle lens at work, which makes it a 2x digitally zoomed in photo. The YouTuber added that the optical zoom doesn’t work if you are too close to the object. Also, the telephoto lens stops working when your phone’s battery is running low. It helps conserve battery life.
Also, many others have found that the iPhone 7 Plus does not use the telephoto lens when you are taking images in low-light conditions. It’s because the phone is always trying to maximize image brightness. The wide-angle lens – which is 28mm wide – boasts of a f/1.8 aperture. It gathers about twice as much light as the 56mm, f/2.8 telephoto lens. That means using the telephoto lens in low-light conditions would mean less light and more image noise.
OIS may also be a factor determining the use of telephoto lens
Apple’s SVP of worldwide marketing Phil Schiller confirmed this in a tweet. The telephoto lens may not work even in indoor locations with artificial lighting where you might think there is sufficient light. Another factor determining the use of telephoto lens could be the Optical Image Stabilization. Only the wide-angle lens has OIS. So, if you are zooming while moving, the software may choose to use only the wide-angle lens, says YouTuber Mac4Ever.
No Issue. In low light (or 10cm macro) the dual camera may use the wide angle 28mm f/1.8 + OIS lens for the best photo #iPhone7Plus
— Philip Schiller (@pschiller) September 17, 2016
Most iPhone 7 Plus users may not give much importance to these details. But if you are going to use your brand new iDevice for professional photography, it may negatively affect the quality of your footage.