Following an earlier test of depth of field, 9to5Mac turns to how the iPhone 18 Pro's variable aperture affects Night mode photos. The widest aperture is boosted from f/1.8 to f/1.48, letting in more light and shortening the exposure needed. In testing, one shot's duration dropped from 2.1 seconds to 1.7 seconds. The difference is modest, roughly less than one stop of extra light, but it may help when a steady hand is hard to maintain. The reviewer notes the biggest gains would appear in very dark settings such as astrophotography, which London conditions did not allow testing.
The aperture also works in the opposite direction. By manually stopping down to f/4, the reviewer increased exposure to 4 seconds, which smoothed choppy water and reduced the spotlights' reflections. The smaller aperture also produced a more pronounced starburst effect around lights. For the ultimate glassy water look, however, a 30-second exposure is needed, which on an iPhone requires a third-party app such as Spectre to combine multiple shots. The reviewer used this method on an iPhone 16 Pro Max to achieve an ice-like smooth finish.
On the question of upgrading, the verdict is that the variable aperture alone is probably not enough reason to move from the iPhone 17 Pro to the iPhone 18 Pro. For owners of older iPhones, however, these night photography benefits could tip the decision toward buying.
Source: 9to5Mac · Summarized by HeadlinesBriefing