Zoom lenses are designed to cover a range of focal lengths.
Rikenon lenses were produced by Ricoh up until the 1980s. They were usually had a "K" bayonet mount on them that would allow them to be mounted to Ricoh and Pentax cameras. The company produced a number of different lenses from wide angles all the way up to 600mm super telephoto lens. They also produced zoom lenses. Their 35-70 and 70-150 were two of the more common zoom lenses they produced.
35-70mm f3.5 Zoom Lens
This manual lens has a number of different features going for it. It is fairly fast lens with a maximum aperture of f3.5 allowing you to use a fast shutter speed when shooting wide open. The lens is ideally suited as a good everyday lens with its focal length of 35-70mm. The lens is also able to focus as close as 30 centimeters, making it a good lens for macro photography. The lens has seven lens groups built inside and seven lens elements. The front diameter is 58 millimeters and has an angle of view of 63 degrees at 35mm to 34 degrees at 70mm.
70-150mm f4.0 Zoom Lens
Designed to be a portrait zoom telephoto lens, this manual lens can also be used as macro lens focusing on subjects as close as 64 centimeters. The lens is a little slower than the 35-70mm at f4.0. The lens is built with 13 lens elements in 10 groups. The angle of view of the lens is 34 degrees at 70mm and 16 degrees at 150mm. The front diameter is 52 millimeters.
Using the Lenses
Both the 35-70 f3.5 and 70-150 f4.0 are designed to replace a number of prime (non-zoom) lenses that you may otherwise carry in your camera bag. For the majority of photographers who are shooting everything from macro work to portraits, these lenses would be all you would need to carry. The lenses are no longer in production but can be purchased either on auction websites or through used camera retail stores.
Tags: Zoom Lens, 35-70 70-150, 35-70mm lens, angle view, close centimeters, degrees 70mm, diameter millimeters
