Canon IV-S

Canon IV-S

The Canon IV-S is a 35mm Leica screw-mount rangefinder camera introduced by Canon in the early 1950s. It belongs to Canon’s synchronized IV-series rangefinder line and represents one of the company’s more advanced LTM cameras before the arrival of the 1/1000-second Canon IV-Sb.

The camera uses a universal threaded mount, compatible with Leica Thread Mount lenses, also known as LTM or M39. It accepts Canon screw-mount rangefinder lenses and other compatible 39mm screw-mount lenses.

The Canon IV-S has a two-axis horizontal-travel focal-plane shutter with cloth curtains. It uses the older Canon shutter-speed sequence with slow speeds on the front dial and faster speeds on the top dial. The top speed is 1/500 second, rather than the 1/1000 second found on the later Canon IV-Sb.

The camera includes Canon’s flash synchronization system of the period. It supports synchronization for slower bulb flash use, FP flashbulbs and electronic X synchronization. This makes it more advanced than non-synchronized Canon bodies such as the II D, while remaining below the IV-Sb in shutter-speed specification.

The viewfinder is Canon’s integrated rangefinder and rotatable viewfinder system with three magnification settings. This system gave Canon rangefinders a more flexible viewing arrangement than many simpler Leica-copy bodies, especially when using different focal lengths or when focusing with greater precision.

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History

Development and Launch

The Canon IV-S appeared during the early 1950s as Canon developed more advanced screw-mount rangefinder cameras with built-in flash synchronization. It followed the earlier IV-series bodies and helped bridge the gap between Canon’s pre-synchronized postwar models and the later IV-Sb.

The model name is usually read as Series IV, synchronized. It should not be confused with the later IV-Sb, which added a 1/1000-second top shutter speed and became one of Canon’s best-known early 1950s rangefinders.

Position in the Canon Line

The Canon IV-S sits above simpler Canon II-series bodies because it has slow speeds and a fuller flash synchronization system. It is closely related to the Canon II S, but belongs to the IV-series body designation.

The simplest way to understand the camera is: Canon IV-S equals a synchronized IV-series LTM body with 1/500-second top speed. The later IV-Sb keeps the same general concept but adds the 1/1000-second shutter speed.

Shutter and Speed Sequence

The IV-S uses the older 1/25-based shutter-speed sequence. The slow-speed dial includes speeds down to 1 second, plus T, X and 1/25 second. The main dial includes B, 1/25, 1/40, 1/60, 1/100, 1/200 and 1/500 second.

This is an important identification point. Later Canon models such as the IV-Sb2 and II S2 moved to the more modern 1/30-based shutter-speed sequence. The IV-S belongs to the earlier synchronized shutter layout.

Flash Synchronization

Flash synchronization is the defining feature of the IV-S compared with earlier non-synchronized models. The body has the Canon side flash rail and synchronization markings associated with bulb and electronic flash use.

The X-sync point is generally treated around 1/25 second, following the older shutter-speed sequence. FP flash synchronization allowed use of flashbulbs at higher shutter speeds, while slower synchronization settings supported other bulb types.

Serial Number Notes

Japanese Leica Copies gives the reported Peter Dechert serial range as 64050 to 115000, with found examples around 6776x to 11198x.

The safest database wording is 64050 to 115000, reported Peter Dechert range, with found examples around 6776x to 11198x. Canon IV-series cameras are often confused in seller listings, so the serial number should be checked together with shutter-speed markings, flash-sync fittings and model identification.

Relationship to Canon IV-Sb

The Canon IV-S should be kept separate from the Canon IV-Sb. The key difference is the top shutter speed. The IV-S reaches 1/500 second, while the IV-Sb reaches 1/1000 second.

Seller listings may sometimes use IV-S, IV-Sb, IVSb or IVS loosely. For matching, the top shutter-speed dial is the most useful check. If the camera has 1/1000 second, it should normally be matched to IV-Sb. If it has 1/500 second and the synchronized IV-series layout, it should normally be matched to IV-S.

Relationship to Canon II S

The Canon IV-S is closely related to the Canon II S. Both have slow speeds, synchronization and a 1/500-second top speed. The II S is usually described as a lower-positioned companion to the IV-Sb concept, while the IV-S belongs to the IV-series naming sequence.

Because these models can be visually and mechanically close, seller listings should be checked for model markings, serial number and shutter-speed layout before matching.

Relationship to Canon IV-Sb2

The Canon IV-Sb2 is a later development with a revised 1/30-based shutter-speed sequence and a 1/1000-second top speed. The IV-S is earlier, has a 1/500-second top speed and uses the older 1/25-based speed layout.

These should remain separate in the database because they represent different shutter generations and different model identities.

Identification

The Canon IV-S is identified by its LTM screw mount, knob-wind body, bottom loading, front slow-speed dial, main shutter-speed dial to 1/500 second, Canon side flash rail, synchronization markings and integrated three-mode finder.

Common listing names include Canon IV-S, Canon IV S, Canon IVS, Canon Model IV-S, Canon 4S, Canon IV-S LTM and Canon IV-S rangefinder. These should point to the same base model.

Collector Notes

The Canon IV-S is an important but often overlooked Canon LTM body because it sits just before the more famous Canon IV-Sb. It offers the full synchronized IV-series handling but without the 1/1000-second shutter speed.

Collectors should check the top shutter-speed dial, slow-speed dial, side flash rail, synchronization markings, shutter curtain condition, rangefinder alignment, finder clarity, film transport, bottom plate and whether the body has been misidentified as a IV-Sb or II S.

The Canon IV-S should be treated as a separate LTM film camera because its synchronized IV-series body, 1/500-second top speed and older 1/25-based shutter sequence distinguish it from the Canon II D, II S, IV-Sb and IV-Sb2.

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Sources

• [1] Japanese Leica Copies. Canon Rangefinder Cameras, Canon IV-S. https://leica-copies-japan.com/Canon.html
• [2] Canon Camera Museum. IV Sb. https://global.canon/en/c-museum/product/film20.html
• [3] Canon Camera Museum. II F. https://global.canon/en/c-museum/product/film22.html
• [4] Canon Camera Museum. II S2. https://global.canon/en/c-museum/product/film25.html
• [5] Canon Classics. Canon IV-S. https://www.canonclassics.com/