MS-Optics Petz 57mm f/2

MS-Optics Petz 57mm f/2

The Petz 57mm f/2 is one of the more accessible designs from Sadayasu Miyazaki of MS-Optics, who built it as a modern, compact homage to the Petzval portrait lens. The original Petzval objective was developed in 1840 by Joseph Petzval and Voigtländer, and was prized for strong center resolution and contrast wide open while remaining limited by field curvature, uncorrected astigmatism, and a swirly background rendering [1]. Miyazaki adapted that idea into an improved four-element, four-group formula for the Leica M mount, marketing it within his lineup as one of the easier MS-Optics lenses to use rather than one of his extreme fast-aperture experiments [1][2]. It was announced in May 2018 [1].

In keeping with the rest of the MS-Optics range, the lens is unusually small and light for a fast standard. It uses a unit-focus design in which the entire front barrel rotates during focusing, so the aperture ring and front element turn with it; in practice this means setting the aperture before focusing [2]. The aperture ring is clickless and rotates roughly 90 degrees from f/2 to f/16, turning in the opposite direction to most M-mount lenses, while the focus ring travels about 120 degrees to the 1 m minimum [2]. There is no focus tab. The 40.5 mm filter thread is reversed (male), so filters mount in the opposite orientation, and a round metal hood is supplied [2]. Although the barrel is not rangefinder coupled in the conventional precise sense and benefits from live view, reviewers note the small body avoids viewfinder blockage on cameras such as the M10 and M6, and the lens fully clears the six-bit code reader [2]. Being an M-mount optic, it adapts readily to mirrorless bodies such as Sony E-mount [2].

Two versions have been documented: a standard model and a "Vario" variant that allows the user to adjust the coma correction of the lens [2]. MS-Optics also produced a later "H Petz" / "MS-H Petz" 57mm f/2 marketed as a Petzval homage, sold through specialist Japanese channels [3]. The maker's own literature describes all eight glass surfaces as multicoated (FMC), and the lens is supplied with a small data sheet carrying MTF graphs, a common touch on Miyazaki's hand-assembled optics [1][2].

Optical qualities

Rendering The Petz 57mm f/2 has a deliberately classic signature: good central contrast and resolution wide open that falls off steadily toward the edges, producing a strong subject-isolation effect that reviewers describe as a distinct, vintage look not found in modern lenses [2].

Sharpness The center is good from f/2, but performance drops noticeably toward the corners, consistent with the maker's MTF data. The lens shows pronounced field curvature, so off-center subjects render much better when focus is set for that part of the frame; the midframe sharpens up by around f/5.6 and the extreme corners remain soft even stopped well down [2].

Bokeh and transitions Background blur is smooth in the central area but turns busier toward the edges, with outlining and double-edged structures typical of the Petzval lineage. The effect is most pleasing at mid distances, where the falloff makes subjects stand out; at longer distances backgrounds can look more distracting, so stopping down one or two stops calms the rendering [2].

Flare resistance Despite multicoating, flare is a weak point. A bright light source just outside the frame can introduce strong veiling flare and reduced contrast, though obtrusive ghosting is limited; shading the lens helps [2].

Distortion and vignetting Distortion is low and largely uniform. Light falloff is modest for such a compact fast lens, measuring around 2 EV at f/2 and easing as the lens is stopped down [2].

Aberrations Lateral chromatic aberration is well controlled. Longitudinal CA shows mild magenta and cyan outlining near the focal plane wide open, comparable to many 50mm f/1.8 lenses, and coma is significant in the corners at f/2 and f/2.8 [2].

History

Development and Launch MS-Optics, the one-man operation of Sadayasu Miyazaki in Japan, introduced the Petz 57mm f/2 FMC for Leica M mount in May 2018 [1]. Miyazaki framed it explicitly as a revival of the Petzval portrait lens, citing the original 1840 design by Petzval and Voigtländer and its reputation for bright, contrasty central imaging paired with field curvature and swirly bokeh [1]. His stated concept was a lens with high central performance that keeps smooth bokeh at the frame edge, in an easy-to-use standard focal length slightly longer than normal [1].

Special editions A "Vario" version with user-adjustable coma correction has been documented alongside the standard model, and a later "H Petz" / "MS-H Petz" 57mm f/2 Petzval homage has also appeared through Japanese collector channels [2][3]. Beyond these, no large factory variant program is widely documented.

Collector Notes As with most MS-Optics lenses, examples are hand-assembled in small numbers and trade on the used market at premium prices, often around 800 USD and up [2]. Buyers should expect the quirky handling, the rotating front and reversed clickless aperture ring, and the reversed 40.5 mm filter thread, and should confirm the original round metal hood is present, since it lacks a normal front filter thread [2]. Verified MS-Optics literature lists a focal length of 57.3 mm and a maximum aperture near f/2.05, slightly different from the rounded marketing figures, and quotes a weight near 110 g against independently measured figures around 114 g; small discrepancies of this kind are normal for these hand-built lenses [1][2].

Sources

• [1] Leica Rumors. New: MS Optics Petz 57mm f/2 FMC lens for Leica M-mount by Miyazaki San. https://leicarumors.com/2018/05/14/new-ms-optics-petz-57mm-f-2-fmc-lens-for-leica-m-mount-by-miyazaki-san.aspx/
• [2] phillipreeve.net (Bastian Kratzke). Review: MS-Optics 57mm 2.0 Petz. https://phillipreeve.net/blog/review-ms-optics-57mm-2-0-petz/
• [3] Shige's hobby. Petzval Hommage MS-H PETZ 57mm F2. https://shige-art.net/en/msoptics-hpetz57/