Minolta MD-300mm/f4.5

Lightweight hand holding 300mm lens was obtained the other day, from Yahoo auction as usual at some reasonable price, 500 yen. The latest Minolta MD 300mm/f4.5 with only 700gr was the reason to obtain, the external condition was great like new but with mould invasion on every surface inside leading to inevitable full disassembling maintenance. Probably, this is why the seller set the cheapest price.

Front and rear elements were easy to access on ordinary Minolta production, but the focusing system was different from those in MC, not all group extension but internal middle group complicated movement, so the lens length does not change while focusing.

2 lenses were so constructed to move independently supported by cam and cam follower design, ordinary common sense shows 3 ponts support to keep the surface flat, but this one was done with only 2 point support, this extraordinary designing was achieved by precision machining technology just like floating piston and cylinder relationship in a combustion motor----2 positions support means piston pin.

For example, former model MC 300mm/f4.5 HF with all group extension system weighs 1,100gr. It's seldom to go out with me because of it's innate gravity though it has good performance.

Anyway, as MD 300mm/f4.5 telephoto lens with 700gr is available even of 50 M pixel format, so it will last me so long.