Leica's R-mount ultra-wide — 19mm f/2.8 ROM with electronic contacts for late R bodies.
The Leica Elmarit-R 19mm f/2.8 (ROM) is an ultra-wide prime for the Leica R SLR system at Elmarit (f/2.8) aperture class. ROM indicates electronic coding for the Leica R8 and R9 bodies — the latest R coupling generation. Leica R mount.
f/2.8 maximum aperture. 19mm focal length (full-frame). ROM electronic coupling (R8 and R9 compatible). Manual focus via SLR viewfinder. At approximately 480g. 77mm filter thread. Leica R mount.
The Leica R system (discontinued 2009) has a dedicated following for its optical quality; R lenses are commonly used on modern mirrorless cameras via adapters. ROM coding provides electronic lens data (aperture, EXIF) to R8/R9 bodies — on modern adapted use, ROM vs non-ROM is irrelevant. The 19mm ultra-wide is Leica's most extreme R-mount wide-angle prime.
On the used market the Leica Elmarit-R 19mm f/2.8 ROM is a premium ultra-wide prime. Condition checks: 77mm front element for marks, ROM contacts condition, aperture blade operation, focus ring smoothness. Leica R mount — requires adapter for use on any current camera; popular for adapted use on Sony FE and L-Mount systems.