The Melles Griot 59 LGB 450 Invaritar F-Mount Base Lens is an F-Mount base lens from Melles Griot. The listing references Nikon AF Nikkor 50mm 1:1.8, tying the product to a 50mm Nikon focal-length designation and an f/1.8 specification within the mounting context. This description identifies the item as a base-lens component designed for F-Mount configurations, aligning with Nikon’s 50mm format in terms of compatibility and form factor. The branding and model line—Invaritar—appear to denote a specific, purpose-built optical interface within Melles Griot’s catalog, suitable for projects requiring a Nikon F-Mount base configuration.
