The CMC-1 became the benchmark other lenses are measured against with extremely high magnification and overall sharpness. The CMC-2 is a follow-up designed to give photographers using compact systems more magnification choices without sacrificing quality. New underwater photographers, or new system owners, will appreciate an easier-to-use lens with more accurate autofocus performance than stronger lenses can offer. More experienced users will find that CMC-2 is an ideal companion to CMC-1, allowing the perfect lens to be selected based on the subject size.
During pre-production testing we noticed a stunning increase in overall image sharpness when comparing shots taken with CMC-2 to those behind a flat port with no accessory lens whatsoever.
It became clear that with both compact cameras at full telephoto and mirrorless interchangeable lens systems the conversion lens markedly improved overall sharpness.
This is counterintuitive, as conventional wisdom implies that any conversion lens reduces image quality. In this case, the flat port degrades overall sharpness, and the optical correction offered by the CMC-2 restores it.
Simply put – an image taken underwater with CMC-2 is sharper than the same image taken with no accessory lens mounted. These are true water-contact corrective optics!
BREAKTHROUGH LENS DESIGN
Prior to the development of the Nauticam accessory macro conversion lenses, achieving "super macro" underwater meant using tools that were designed for in-air use. These tools simply do not take into account the physics of shooting in water. Thanks to Edward Lai, Managing Director of Nauticam, the CMC-2 takes a radically different approach: hundreds of engineering hours utilizing computer software to model an accessory lens that complements an entire system – camera, lens, port, air, and water – as a whole. This accounts for the critical air-water interfaces in a conversion lens design to achieve the best image quality possible. The improvements are stunning, measurable and a new standard in underwater macro imaging.
UNCOMPROMISING OPTICAL QUALITY
The CMC-2, like all Nauticam Macro Converters, is constructed from lenses precision crafted of specially formulated low dispersion optical grade glass, ground to the most demanding standards. This means greater sharpness and contrast on every shot and extraordinary resolution rivaling a macro lens used in air. Broadband anti-reflective coatings effectively reduce common optical issues such as chromatic aberrations, coma, spherical aberration, and field deformation associated with underwater macro photography using traditional magnifying lenses. This means superior light transmission, accurate color and no distortion and vignetting in the most demanding situations.
These exceptional optics are assembled in a rugged hard anodized aluminum housing, and nitrogen purged during assembly to eliminate fogging.
The CMC-2 is the less powerful of the two Nauticam Macro Converters designed for compact cameras, but magnification when compared to the capabilities of these cameras with no accessory lens is still very impressive.
As an example, the popular Sony RX100V can capture an image area 160mm (6.3 in.) wide at its full telephoto zoom position at its minimum focus distance. With the addition of CMC-2, that image area is reduced to 55mm (2.2 in) wide. CMC-1 brings the minimum focus distance even closer, allowing a captured frame 36mm (1.4 in) wide.
OPTIMIZED FOR AUTOFOCUS
By utilizing a specially developed algorithm in the lens design process, the CMC-2 renders superior image quality over the full focusing range of the camera lens. This, combined with the high brightness and contrast of the image, allows the autofocus system of the camera to work well – often better than less powerful close focus lenses. Just as important are the out-of-focus (Bokeh) portions of the image that exhibit the same creamy smooth quality that photographers appreciate when shooting macro in air – all without color fringing common to traditional magnifying lenses.
Due to the overall superior optical performance and precision focus of the CMC-2 it is possible to shoot larger apertures with excellent image quality. This avoids reaching the diffraction limit of high resolution sensors, and allows selective focus effects with narrow depth of field in super macro images.
MOUNTING, AND USING THE CMC-2
The CMC-2 ships with the common 67mm threaded lens mount. The lens has a protruding rear element, designed to place the accessory optic as close to the camera lens port as is possible, providing the best overall image quality when used with flip lens adapters. A flush mount adapter ring is used when attaching CMC-2 directly to an underwater housing, and is included with the lens. Flip and Bayonet Lens Mounts are available as accessories.
The same Nauticam bayonet system designed with the Wet Wide Lens (WWL-1) is also compatible with CMC-2. (P/N 81302). The bayonet mounting system is the attachment method of choice for shooting both macro and wide angle on the same dive.
Nothing beats the convenience of flip adaptors, allowing the accessory lenses to be flipped in place when needed, and conveniently swung out of the way for normal lens shooting. A flip adaptor is the best mounting system for macro only dives, or camera systems that don't support macro and wide angle lenses on the same dive (such as Canon G7X Mark II)
The new M67 Double Flip Holder for M67 Macro Ports, P/N 25108 allows both CMC-1 and CMC-2 to be used on the same dive for multiple macro framing options.
A WORD ON MAGNIFICATION
The industry standard macro lens magnification measure is a dioptric power, but we don't feel that is actually that useful. Dioptric numbers can be misleading. They are often multiple lenses stacked together, and the resulting stack doesn't always yield the power of its individual components.
In an attempt to make the power and utility of these lenses less confusing, we offer a simplified magnification factor. CMC-2 offers 2.8x magnification (as an average) with compact cameras currently supported by Nauticam housings. For comparison, CMC-1 results in 4.5x average magnification.