I have heard rumors on the Internet that AI lenses cannot be focused at infinity on entry-level Nikon DSLRs. Can someone who uses AI lenses on their entry-level Nikon camera either confirm or deny this, based on personal experience?
I regularly use 8 to 10 AIS, AI and non-AI lenses on my D3200 and D5100. There is absolutely no problem reaching ∞ on any of them. Plus the hard ∞ stop is right on the money. Whoever is spreading this rumor either has broken equipment or is a troll and doesn't know what they're talking about.
Welcome to Nikonians! You are confusing Nikon with Canon.
All Nikon DSLR's support AI, AI modified, and AIS MF lenses including the ability to focus to infinity without an adaptor.
To use a Canon MF (FD) lens on a Canon DSLR you will need an adaptor with a lens element to support focus to infinity.
I can confirm that AI modified, AI, and AIS MF lenses focus to infinity on Nikon entry level DSLR's as well as the Pro bodies. Keep in mind that the entry level DSLR's do not support metering when used with MF lenses without CPU's. You will be limited to Manual exposure mode, Manual ISO, and Manual or Non-TTL Auto flash modes. The D_ series, D_00 series, and D7000 support metering with AI, AI modified, and AIS type MF lenses without CPU's. Good Luck and Enjoy your Nikons!