The Galaxy Note 10 could bring an important upgrade to the telephoto camera that we've been seeing on every Galaxy flagship since the Galaxy Note 8. The Note 10 and Note 10+ will reportedly have an F2.1 telephoto lens instead of an F2.4 lens that Samsung has been using all this time, which means we could see notably improved low-light performance in the 2x zoom photos that the telephoto camera makes possible.
More importantly, the Note 10 and Note 10+ most likely won't have to depend on digital zoom with the primary 12MP camera in low-light conditions. Yes, your Galaxy Note 8, S9, Note 9, or Galaxy S10 don't always use the telephoto lens when you tap that zoom button in the camera app. They simply switch to digital zoom with the main camera when there's not enough light, as the F2.4 aperture of the telephoto lens is simply too small to be of much use in such situations.
In layman terms, the aperture is the opening through which light enters the lens, and a higher aperture number is equal to a narrower lens opening, and vice versa. And with an aperture of F2.1, the telephoto camera will be slightly better than the ultra-wide camera (which is reportedly retaining its F2.2 aperture) in low-light conditions. The wider aperture should also enable the use of Night mode with the telephoto camera, allowing for more detail and brighter pictures; the front camera is rumored to be getting Night mode support as well.
The three-stage aperture for the primary camera, a wider aperture for the telephoto camera, and the addition of an ultra-wide camera will make the Galaxy Note 10 and Note 10+ excellent upgrades in the imaging department for owners of Galaxy flagships from before the Galaxy S10. It would even give Galaxy Note 9 owners good reason to make the switch to a Note 10 or Note 10+, as long as they can look past some of the limitations the new Notes will bring along.
