The Nikon AIS (Automatic Indexing Shutter) lens system was a popular feature in many Nikkor lenses produced from the late 1970s to the late 1980s. This system provided a unique way of communicating aperture information between the lens and the camera body, resulting in improved exposure control and metering accuracy. Today, many photographers still use these AIS lenses for their excellent optical quality and compatibility with modern Nikon DSLR and mirrorless cameras. If you’re wondering how to tell if a Nikkor lens is AIS, here are a few key indicators to look for.
1. Aperture Ring with F-Mount: One of the most obvious signs of an AIS lens is the presence of an aperture ring on the lens barrel. This ring allows you to manually select the aperture setting, which is a distinctive feature of AIS lenses. Additionally, AIS lenses are designed with a traditional Nikon F-mount, enabling them to fit seamlessly on a wide range of Nikon camera bodies.
2. AI Coupling Prong: Another characteristic of AIS lenses is the presence of an AI coupling prong on the lens mount. This prong interacts with the camera’s metering system to transmit aperture information, allowing for accurate exposure control. If you see this prong on the lens mount, it’s a strong indication that the lens is an AIS model.
3. Suffixes or Markings on the Lens: Many AIS lenses are labeled with specific suffixes or markings that identify them as part of the AIS system. For example, you may see “AI” or “AIS” engraved on the lens, indicating its compatibility with Automatic Indexing features. Additionally, some AIS lenses may have a silver AI-s index mark on the aperture ring, highlighting their enhanced functionality.
4. Compatible with Modern Camera Bodies: AIS lenses are fully compatible with modern Nikon DSLR and mirrorless cameras. If you have a lens and are unsure of its classification, try mounting it on a newer Nikon camera body. If the camera is able to communicate with the lens and read aperture settings, it’s likely that the lens is an AIS model.
5. Online Resources and Documentation: If you’re still uncertain about the classification of your Nikkor lens, consider consulting online resources or official Nikon documentation. Websites, forums, and manuals can provide valuable information on identifying and understanding different lens models, including AIS lenses.
In conclusion, determining whether a Nikkor lens is an AIS model involves examining its physical characteristics, compatibility with camera bodies, and any identifying markings or suffixes. AIS lenses are prized for their excellent optical performance and seamless integration with modern Nikon cameras. By familiarizing yourself with the distinctive features of AIS lenses, you can make informed decisions when building your collection of Nikon-compatible lenses.
