LENS HANDLING AND BUILD QUALITY

I am a sucker for a nicely made lens and the Contax 18mm Distagon easily falls into that category. The build is excellent. The lens feels solid and very well constructed. In terms of build quality and feel, the Contax 18mm is my favorite Contax lens. The 18mm Distagon is a compact lens and only about 1/3 the size of a Canon 16-35L F2.8 II. The picture above shows the Contax 18mm in front of a Canon 35mm F1.4 L and a Canon 200mm F2.8 L II. As travel lens the Contax 18mm is light, small and easily fits into a camera bag.

The 18mm Distagon’s manual focus ring is sublime and probably the smoothest focusing Contax lens. The focus ring only requires a light touch - very Leica-esque. Like all the Contax RTS lenses, the aperture ring clicks in full stop increments. This is fine for landscapes since most scenes are typically shot at F8 or F11. The 18mm Distagon uses the Contax 70-86 Metal Ring as a combination hood / filter adapter. The Contax specifications state to use the Contax #1 Metal Hood, but in my opinion the 70-86 ring did well enough.

The Contax 70/86 rings are difficult to find and sell for $75 to $150. The Contax 70-86 ring is not a must have, but it is handy. The front portion of the 18mm Distagon’s barrel rotates as the lens is focused. The Contax 70-86 adapter ring attaches to barrel (held in place by pressure), thus the attached filter will also rotate. In the case of a polarizer or graduated filter this can be irksome.

The 18mm Distagon comes with a 70mm push-on rubber cap for the front element. These caps are also difficult to find too, so make sure the seller includes the original Contax 70mm push-on cap. A 70mm Kaiser push-on cap (available here at B&H Photo) works as a replacement, but for $9 do not expect much. The original Contax cap is a thick, hard rubber-like plastic that provides impact protection. The Kaiser cap is a thin plastic which flexes easily. It covers the front element, but provides minimal protection. Again, for $9 it is fine.

LENS PERFORMANCE

Zeiss advertised the Contax 18mm as a compact design with sharp corner performance and excellent distortion correction. Part of the performance is attributed to the floating lens element design (commonly referred to as “FLE”). A floating element design improves near field performance - both in terms of sharpness and resolution.

The achilles heal of the Contax 18mm is its light fall-off in the corners. Light fall-off in the corners is normal and all lenses have it to varying degrees. In the case of the 18mm Distagon the fall off is pronounced when shot wide open (F4). These days light-fall off is easily fixed via most raw editing software; however, the light fall-off can compromise metering. If metered for the center, then corners are under-exposed. If metered for the corners, then the center is blown out. To be fair, the light fall is not an issue at F8 or F11. However, shooting F11 is not always possible because of moving subjects, or windy conditions, or in low light settings such as a sunset or sunrise.

My suggestion is to meter for center of the image and fix the light fall in post processing. Most modern dSLRs have very good noise performance and produce clean shadows which can be boosted in post processing without taking a noise hit. If shooting at F4, the Contax 18mm will produce a very classic rendering. Some people may like the light fall off, so it really comes down to taste and preference. I like light fall off and tend to add some during post processing, so the 18mm Distagon’s light fall off is a non-issue for me. But, I do keep a watchful eye on metering and exposure compensation when shooting at wider apertures.