The Kenko mount has long been recognized in Japan as the best portable mount in its class due to its compactness, which is achieved without sacrificing load capacity or tracking accuracy. This is achieved by utilitizing precision components and conservative construction as shown in the photo at right. Tracking performance (see sample photos) depends on accurate alignment of the mount, load weight and balance, aim point, atmospheric refraction (at lower altitudes), and other factors. However, as a guideline, the manufacturer-suggested maximum tracking times (unguided) for various focal lengths are: Focal Length (mm)   Max. exposure (minutes) 50 70 100 40 135 35 200 30 300 15