Wide-Angle-Tri-Elmar-M 16-18-21mm f/4.0 ASPH

With its impressive angle of view of 107°, this new TRI-ELMAR conquers 16 mm super wide-angle photography in perfect Leica M style. Due to the minimal distortion and barely perceptible field curvature, it can be recommended for highly demanding architecture photography even at the 16 mm setting. Used on the digital M8, it produces the image effect of a 21 - 28 mm lens, still enabling extreme wide-angle views. The ultra compact shape is achieved by two aspherical elements. A new design of the interior focusing significantly enhances the quality in the close-focus range through an adaption of the floating element principle. Brilliant field depth can therefore be used from a distance of 0.33 m for hyperfocal photography.

Angle of view (diagonal, horizontal, vertical)
for 35 mm and M9 (24 x 36 mm) at 16 mm: 107°, 97°, 74° 
at 18 mm: 100°, 90°, 67° 
at 21 mm: 92°, 81°, 60° 
for digital M8/M8.2 (18 x 27 mm)

at 16 mm: 90°, 80°, 59° 
at 18 mm: 84°, 74°, 53° 
at 21 mm: 75°, 65°, 46°

corresponds approx. to a focal length of 21/24/28 mm with 35 mm-format 

Optical design
Number of elements / groups 10 / 7
Distance setting
Focusing range 0.5 m to Infinity, range from 0.5 to 0.7 m separated by index
Scales Combined meter/feet graduation with uniform grey figures below 0.7 m
Smallest object field at 16 mm: 915 x 1373 mm, approx. 1:38 
at 18 mm: 833 x 1250 mm, approx. 1:35 
at 21 mm: 725 x 1087 mm, approx. 1:30
for M8 digital at 16 mm: 688 x 1032 mm, approx. 1:38 
at 18 mm: 626 x 939 mm, approx. 1:35 
at 21 mm: 545 x 817 mm, approx. 1:30
Highest reproduction ratio: at 0,7 m at 16 mm: 1:38 
at 18 mm: 1:35 
at 21 mm: 1:30
Aperture
Setting / Function Preset, with click-stops, half values available
Lowest value 22
Bayonet Leica M quick-change bayonet with 6 bit lens identification bar code for digital M models
Filter (type) Male thread, non-rotating and with stop for filter holder or lens hood 
Lens hood screw-on type lens hood (included in delivery), filter holder for E67 size filters optionally available
Dimensions and weight
Length approx. 62/72 mm (with/without lens hood)
Largest diameter approx. 54 mm (53 x 58 mm with lens hood)
Weight approx. 335 g