Recent Posts21
Camera Talk / Re: The Lens Adapter Nikon REFUSED to Build
« Last post by Les Olson on February 12, 2026, 04:12:54 »Pentax introduced the K mount in 197something, and it has retained backward and forward compatibility right up to now. And much good it did them.
When the F mount was introduced in 1959, and for years after, all it had to do was make a stable, light-tight connection between the camera and the lens. What was there to change? Of course, 44mm diameter is too small for film with a diameter of 43mm, but no one who cared about image corners used 35mm. In 1977 Nikon introduced Ai lenses, and although it was all still F mount, so what they said in 1971 was true, backward compatibility was cracked, if not broken. Notably, although Nikon made it easy and relatively inexpensive to convert most pre-Ai lenses to Ai there were pre-Ai lenses that Nikon would not convert to Ai.
SLR sales were strong in the 1970s. In particular, Canon sold a million (literally) of the AE-1, marketed with the slogan "About all you do is focus and shoot" - this was the first SLR with full auto-exposure - but manual focus turned out not to be as easy as Canon made it sound (which is why you can go to KEH today and find plenty of AE-1s in mint condition) and after AF compact cameras appeared in 1977 the SLR market tanked. Compact cameras went from 43% of the market in 1977 to 81% in 1987. In March 1983, Nikon introduced the L35AF "Pikaichi" and in 1984 its sales exceeded sales of all seven Nikon's SLRs - F3, FA, FE2, FM2, FG, FG-20 and EM - put together.
Obviously, the solution was to make SLRs with AF, but the first AF cameras failed (the F3AF, eg), because the cameras were much more expensive than the MF versions, you had to buy new AF lenses, and the AF was not very good. Then in 1985 Minolta introduced the 7000 (Maxxum in the US) with a new A (later Sony Alpha) mount that trashed backward compatibility but had AF that worked. It turned out nobody minded buying new lenses if you got good AF, and in 1986 Minolta was the SLR market leader, with more than 50% of sales. Canon decided it couldn't do competitive AF with the FD mount, and in 1987 introduced the EOS 650 with the larger and fully electronic EF mount, completely trashing backward compatibility. By 1989, 90% of SLRs sold had AF, Canon was market leader and Nikon, the only one who had not trashed backward compatibility, was in third place.
Apparently, backward compatibility hasn't always been what it is now.
When the F mount was introduced in 1959, and for years after, all it had to do was make a stable, light-tight connection between the camera and the lens. What was there to change? Of course, 44mm diameter is too small for film with a diameter of 43mm, but no one who cared about image corners used 35mm. In 1977 Nikon introduced Ai lenses, and although it was all still F mount, so what they said in 1971 was true, backward compatibility was cracked, if not broken. Notably, although Nikon made it easy and relatively inexpensive to convert most pre-Ai lenses to Ai there were pre-Ai lenses that Nikon would not convert to Ai.
SLR sales were strong in the 1970s. In particular, Canon sold a million (literally) of the AE-1, marketed with the slogan "About all you do is focus and shoot" - this was the first SLR with full auto-exposure - but manual focus turned out not to be as easy as Canon made it sound (which is why you can go to KEH today and find plenty of AE-1s in mint condition) and after AF compact cameras appeared in 1977 the SLR market tanked. Compact cameras went from 43% of the market in 1977 to 81% in 1987. In March 1983, Nikon introduced the L35AF "Pikaichi" and in 1984 its sales exceeded sales of all seven Nikon's SLRs - F3, FA, FE2, FM2, FG, FG-20 and EM - put together.
Obviously, the solution was to make SLRs with AF, but the first AF cameras failed (the F3AF, eg), because the cameras were much more expensive than the MF versions, you had to buy new AF lenses, and the AF was not very good. Then in 1985 Minolta introduced the 7000 (Maxxum in the US) with a new A (later Sony Alpha) mount that trashed backward compatibility but had AF that worked. It turned out nobody minded buying new lenses if you got good AF, and in 1986 Minolta was the SLR market leader, with more than 50% of sales. Canon decided it couldn't do competitive AF with the FD mount, and in 1987 introduced the EOS 650 with the larger and fully electronic EF mount, completely trashing backward compatibility. By 1989, 90% of SLRs sold had AF, Canon was market leader and Nikon, the only one who had not trashed backward compatibility, was in third place.
Apparently, backward compatibility hasn't always been what it is now.
)