The Leica Summaron 35mm f/3.5 with OVU goggles (SOONC-M, 11105) is an M-mount classic prized by M3 users for its compact build and vintage character.</parameter> <parameter name="long_description">## Leica Summaron 35mm f/3.5 with OVU SOONC-M What sets this version of the Summaron 35mm f/3.5 apart is the OVU optical attachment, the pair of auxiliary "goggles" that sit in front of the rangefinder and viewfinder windows. The Leica M3, the camera the lens was designed to accompany, has no built-in 35mm frame line, so the goggles magnify the wider field down into the M3 finder and bring up the correct framing while keeping the rangefinder coupled. The result is a lens that lets M3 owners shoot 35mm without an accessory finder, and the assembly is why collectors single out this configuration, catalogued under model number 11105 [1][2]. Optically the lens uses a six-element, four-group design, and the same formula was carried across the screw-mount and bayonet versions of the lens [2]. The bayonet M version was produced toward the end of the Summaron 35mm f/3.5 run, which spanned roughly the mid-1940s to about 1960 in screw mount and the second half of the 1950s in M mount [2][3]. The barrel is short and light, in keeping with other compact Leica wide angles of the era, and build quality is regularly described as excellent, with many surviving copies still working smoothly and remaining largely free of internal dust [2][3]. The diaphragm uses ten blades, which keeps the aperture opening close to circular and contributes to the lens's gentle out-of-focus rendering [2]. The lens is rangefinder coupled, takes 39mm filters, and focuses to one meter. Because the optical cell is shared between mounts, the most important identification point is the mount and the presence of the goggles rather than the glass itself. A goggled f/3.5 Summaron in M bayonet, carrying the SOONC-M designation and model number 11105, is distinct from the plain screw-mount lens used with an adapter and from the later faster f/2.8 Summaron, which is a different optical design and is not covered here [2][3]. --- ## Optical qualities **Rendering** The Summaron 35mm f/3.5 is valued more for character than for clinical correctness. Reviewers describe a lens that is not flawless wide open but renders with a distinctive, atmospheric quality, combining mild softness, vignetting and a particular tonal feel that suits mood-led and black-and-white work [3]. It was designed in an era when monochrome was the dominant medium, and users note that it performs at its best in good light, where it can still produce smooth, pleasant out-of-focus areas helped by the ten-bladed diaphragm [1][3]. Those drawn to it generally want the classic vintage Leica look and a rendering that differs visibly from modern optics, rather than maximum sharpness across the frame [1]. --- ## History **Development and Launch** The Summaron 35mm f/3.5 was one of Leica's common wide-angle lenses of the period, first offered in screw mount and later adapted to the M bayonet [2][3]. With the introduction of the M3 in 1954, Leica needed a way to use a 35mm lens on a camera whose viewfinder lacked a 35mm frame line, and the goggled SOONC-M version answered that need by adding the OVU optical attachment to the bayonet lens [1][2]. **Production Evolution** The lens kept its six-element, four-group optical formula across both the screw-mount and M-mount versions, so the principal change over its life was the mount and the addition of the finder goggles for M3 use rather than a new optical design [2]. Production of the f/3.5 Summaron ran to about 1960, after which Leica's 35mm offerings moved on to faster designs [2][3]. **Special editions** No major factory special editions of this specific goggled f/3.5 version are widely documented in collector sources beyond the standard SOONC-M configuration recorded as model 11105 [1][2]. **Collector Notes** For an M3 user the goggled Summaron is often regarded as both a usable lens and a desirable collector item [1]. When evaluating a copy, confirm that the goggles are present, undamaged and clear, since they are integral to correct framing on the M3 and are awkward to replace. As with any lens of this age, check the front and rear glass and internal elements for haze, fungus and separation; many surviving examples remain clean, but condition varies. The 39mm filter thread and period caps and hoods are worth verifying as original. Note also that the plain screw-mount Summaron and the later f/2.8 Summaron are easily confused with this version in listings, so checking the mount, the goggles and the model number helps avoid mistaken purchases [2][3]. --- ## Sources * [1] Dankerin Photography. *Leica 35mm F3.5 Summaron*. https://dankerinphotography.com/leica-35mm-f35-summaron * [2] Vintage Camera Lenses. *Leica Summaron 35mm f3.5*. https://vintage-camera-lenses.com/leica-summaron-35mm-f3-5/ * [3] MrLeica (Matt Osborne). *Leica Summaron 35mm f3.5 Review & Photos*. https://mrleica.com/summaron-35mm-f3-5/

Leica Summaron 35mm f/3.5 with OVU SOONC-M

M mount