SLR camera lens how to see is not a constant aperture
3, the smallest aperture if it is two, then the maximum aperture must also correspond to two, you may be wrong information. For example, F3.5-5.6 corresponds to F22-38.
2, constant aperture is in the zoom lens of the focal length of the focal length of the lens are the same, such as 70-200 / F2.8 (only one maximum aperture value), rather than the constant aperture is the zoom lens in the focal lengths have different maximum Aperture value, such as 70-300 / 4-5.6. Constant aperture in use is easier to control, the general constant aperture zoom lens are high-end, but non-constant aperture lens is often smaller because of the volume of light and more portable.
1, constant aperture is certainly better than non-constant aperture, the price difference is great. Constant aperture volume is relatively large.
