From Nikon I to Nikon M

One of the big dilemmas with the Nikon I, was its picture size (the "Nikon" format of 24 x 32 mm) which did not correspond to the US automatic color slide cutting machines which operated with the Leica format (24 x 36 mm).

Because of this problem, the headquarter office did not permit the export of the Nikon I.

To solve the dilemma, the camera's frame size was to be changed to a 24 x 36 mm size, thus came up with the migration to a new camera model.

The Nikon M rangefinder is a significant camera in Nikon's early history, marking a step in the evolution of their highly regarded rangefinder camera system. It followed the very first Nikon camera, often retroactively referred to as the "Nikon I."

Here's a detailed look at the Nikon M:

1. Place in Nikon's Lineage:

• Successor to the Nikon I: The Nikon M was introduced in 1950, a couple of years after Nikon's very first 35mm rangefinder, the Nikon I (released in 1948).

• Predecessor to the Nikon S: It was then succeeded by the Nikon S in 1951, which in turn led to the highly popular and influential Nikon S2, SP, S3, and S4 models.

2. Key Characteristics and Features:

• Film Format: One of the most notable aspects of the Nikon M is its film format. While the Nikon I used a unique 24x32mm "Nikon format" (to get more frames per roll), the Nikon M increased this slightly to 24x34mm. This was still not the standard 24x36mm "Leica format," which Nikon would fully adopt with the S2.

The prototype of that was completed in July 1949, and it was decided that this model would be put on the market as the Nikon M, with a M at the front of the Serial No. The Nikon M was released in October 1949. It was still irregular in picture size but changed to 36 frames, therefore removing the impediment for export.

Lens Mount: Like all early Nikon rangefinders, it used the Nikon S-mount. This mount was mechanically based on the pre-war Contax rangefinder mount, featuring both an inner bayonet (for 50mm lenses) and an outer bayonet (for wide-angle and telephoto lenses).

• Compatibility Note: Due to slight differences in flange distance and focusing helicoid travel, while wide-angle lenses were generally interchangeable between Nikon S-mount and Contax cameras, 50mm and longer lenses were not reliably cross-compatible for accurate focusing across the entire range.

• Shutter: It employed a horizontal cloth focal plane shutter, similar to Leica's design, which was known for its reliability compared to some other designs of the era. Shutter speeds typically ranged from 1 second to 1/500th of a second, plus Bulb (B) and Time (T) modes.

• Flash Synchronization: Early versions of the Nikon M lacked flash synchronization. However, later versions, often referred to as "Nikon M Synchro," added flash sync contacts via an accessory shoe on the top panel.

• Viewfinder/Rangefinder: It featured a combined viewfinder and rangefinder. The rangefinder was of the split-image and superposed-image type for focusing.

• Film Advance/Rewind: Like the Nikon I, it used a knob film wind and rewind mechanism, which was slower to operate than the later lever advances introduced with the S2.

• Construction: Generally made with a metal body, often in a chrome-silver finish. Some rare black versions were custom-made.

• "Made in Occupied Japan": Many Nikon M cameras (and their lenses) bear the engraving "Made in Occupied Japan" (MIOJ) due to the post-WWII Allied occupation.

It is also important to watch out that the Serial No on the camera body should always match that on the back, since many parts would have been mixed due to the scarcity of good example of these antique cameras.

From 1947, the production of the 50mm f/2 (product name was NIKKOR-H.C 5 cm f/2) was started as the standard lens. It was to note that they were marked as "Nippon Kogaku Tokyo", instead of "Nippon Kogaku Japan" on the later productions.

3. Historical Significance and Collectibility:

• Rarity: The Nikon M had a relatively short production run, with around 1,643 units produced. This makes it a considerably rarer and more collectible camera than later Nikon rangefinder models like the S2, SP, or S3.

• Evolutionary Step: It represents a crucial transitional phase for Nikon as they refined their camera design and gained recognition in the global photographic market. The lessons learned from the Nikon I and M directly influenced the improved and more successful models that followed.

• Korean War Connection: Nikon rangefinders, including the M and later S models, gained significant international recognition when Life magazine photographer David Douglas Duncan used them extensively during the Korean War, praising their quality and durability.

4. Identifying a Nikon M:

• The most distinct characteristic is often the "M" preceding the serial number.

• The 24x34mm frame format (though hard to tell without shooting film).

• The presence or absence of flash synchronization (later models have it).

The Nikon M is a fascinating piece of photographic history, demonstrating Nikon's early efforts to establish itself as a precision camera manufacturer and laying the groundwork for its legendary success in the decades to come.

Reference

https://imaging.nikon.com/imaging/information/

Nikon Rangefinder Camera - An Illustrated History of the Nikon Rangefinder Cameras, Lenses and Accessories by Robert Rotoloni