Bolex H16 Reflex (1956)

Name: Bolex H16 Reflex
Brand: Bolex

Ten prisms, one spring, and a groundglass that shows you exactly what the film will see. This is the camera that put through-the-lens framing in a filmmaker's hands.

Overview

The Bolex H16 Reflex is a 16mm spring-wound film camera built by Bolex International S.A. of Yverdon, Switzerland. It was introduced in 1956 as the reflex-viewing version of the original H16, which debuted in 1935. It is a manual-focus, C-mount cine camera with variable speed from 12 to 64 fps and a triple-lens turret. It has no batteries, no electronics and no auto-exposure. All it carries is a governor-controlled spring motor, a reflex prism, and gears.

The viewing system is what separates the Reflex from the non-reflex H16s before it. A system of ten optical prisms was used to create through-the-lens framing and focusing, so the operator sees the picture as it will appear on film, with sharp and blurred areas faithfully reproduced. Unlike cameras such as the Arriflex, the H16 Reflex did not do this with a mirrored shutter. It placed a prism behind the lens that directed part of the image to the viewfinder. The prism diverts 20-25% of the light to the eye while 75-80% reaches the film. That is a reduction of roughly one-third to one-half of an f-stop, and the Bolex exposure meter was calibrated to account for it.

The body is polished duraluminium covered in Morocco leather with chrome-plated metal parts. It measures 8.5" x 6" x 3" (216 x 152 x 76 mm) and weighs approximately 5.5 lbs (2.5 kg). It loads 100 ft (30 m) daylight spools with automatic threading and loop forming. The film transport has no registration pin, and some professionals criticized that at the time as compromising image steadiness. The precision of the claw mechanism and film loop control seems to compensate well enough in practice.

Key Features

Through-the-Lens Reflex Viewing with a Ten-Prism System

The reflex viewfinder shows the picture as it will appear on the film. It does more than frame. It lets the operator estimate depth of field, judge the correct focal length, check the filter in use, and evaluate scene illumination. Magnification is 6x on a groundglass screen, with an adjustable eyepiece. The manual notes the picture formed on the ground glass of the reflex prism is absolutely free from flicker. The trade-off is brightness. The viewfinder is dark by modern standards, and the prism's light theft has to be compensated for in exposure. The viewfinder's field can be adapted for lenses of 16, 25, 35, 50, 63, 75, 100, or 150 mm. A sliding auxiliary lens adapts it to a 10 mm wide-angle when set to the shortest focal length.

Triple-Lens Rotating Turret in C-Mount

The turret holds three C-mount lenses and indexes with three click stops so each lens sits correctly in front of the filming aperture. C-mount thread diameter is 25.4 mm (1"), maximum thread length is 4.06 mm (.160"), and the film plane-to-lens seat distance is 17.52 mm (.690"). Lenses 50mm and shorter must be "RX" corrected for reflex viewing. Standard C-mount glass of that focal length will show a darkened corner in the viewfinder even when the film gate is fully illuminated. Telephoto lenses from 50 to 150 mm can generally be used on the Reflex or on non-reflex bodies alike. A common set was 16mm, 25mm (standard), and 75mm or 50mm. When mounting heavy zooms or long telephotos, lock the turret with a clamp.

Governor-Controlled Spring Motor

Power comes from a constant-speed, spring-wound clockwork motor under governor control, which keeps exposure consistent across frames. The manual lists seven filming speeds - 12, 16, 18, 24, 32, 48, and 64 frames per second. You select one by turning a control knob until the figure meets a red dot. At 24 fps a fully wound spring runs about 28 seconds. A 100 ft spool lasts 2 min. 44 sec. at 24 fps, 3 min. 38 sec. at 18, and 1 min. 1 sec. at 48. Bolex warns against running an unloaded camera above 32 fps, as it can damage the mechanism. An external electric motor could be coupled for absolutely constant exposure time and to eliminate the slight flicker inherent to spring drive.

Variable Shutter, 133°–145°

The shutter aperture can be varied both while the camera runs and while it is stopped. This reduces exposure time without changing filming speed. It is useful in dazzling light such as snow or water scenes, where it can eliminate the need for a neutral density filter. The lever locks in four positions. The ¼ and ½ closed positions are marked ½ and 1, meaning the diaphragm should be opened half a stop or a full stop respectively. A triangular warning signal appears in the reflex viewfinder whenever the shutter is not fully open. At 24 fps, the effective shutter speed works out to roughly 1/80 second.

Single-Frame, Time Exposure, and Hand Cranking

The side release handles normal run, continuous filming (M), and single-frame exposures (P). For single frame, the exposure control knob selects instantaneous (I) or time (T), the latter for poor lighting indoors. Bolex advises opening the variable shutter fully for time exposures or one of its blades may mask part of the picture. It also advises using a cable release to prevent camera movement. The mechanism can also run in reverse by means of a small auxiliary crank. Disengage the motor, move the side release to M, close the variable shutter so as not to fog the film, and turn the crank in the direction of the engraved arrow without exceeding the speed governor. That reverse capability is what makes lap dissolves, double exposures, and other trick effects possible. The manual is explicit, though, that the reverse system is designed for rewinding only and should not be used for filming.

Filter Slot Behind the Lens

A filter slot sits between the taking lens and the reflex prism, so gelatine filters stay in place whichever lens is on the turret. The set comprises four filter holders, a cutting frame, and four 2" square gelatine filters. When shooting without a filter, leave an empty holder in the slot to prevent light infiltration that would fog the film. The mount needs to be firmly seated. Diaphragm corrections are approximate: a Wratten 85 needs about ⅔ stop, a Wratten 8 yellow about one stop, and a neutral density 06 about two stops, while a 1A Skylight requires none.

Footage and Frame Counting

A twin-dial frame counter tracks frames individually and in total. A distinct click announces every 10 inches of film passing through the gate, which is handy for anyone counting exposures on a time-lapse or stop-motion shoot. A lever allows the audible signal to be suppressed when noise discipline matters.

Automatic Threading and Loop Forming

Loading is simple. The camera takes 100 or 50 ft spools of single- or double-perforated 16mm film, and the threading and loop forming are automatic. Bolex's own manual advises against striped magnetic film, warning that the magnetic layer can cause premature wear on parts that contact it, particularly the pressure pad, and that metal particles may find their way into the mechanism. The manual also notes a 400 ft magazine can be attached, but only on Rex 5 bodies or converted units.

Historical Context

The H16 line began in 1935. The 1956 introduction of the reflex viewfinder version gave independent filmmakers, students, and artists a camera with professional-level control in a portable, mechanical package. It played a central role in avant-garde, experimental, documentary, ethnographic, and animation filmmaking from the 1940s through the 1970s. It was also a popular introductory camera in film schools, where generations of directors cut their teeth on its unforgiving, frame-by-frame discipline. The Reflex was succeeded by the H16 REX in 1959, which added a variable shutter and a highly polished duraluminium body. The trailing number "5" in later H-model names identified bodies with the built-in 400' magazine saddle. Sources describe the broader H16 family as remaining in production for more than fifty years.

Collectibility & Value

The H16 Reflex remains a working tool as much as a collectible. Recent eBay sales run from $430 to $3,500 with a median around $1,296 across 84 completed sales in a twelve-month window. One 2024 listing recorded a mint, serviced unit with three lenses selling for approximately 1990 euros. Current listings sit in a similar band: a body with a Kern 25mm f/1.4 AR C Switar at $1,079, a kit with four lenses at $1,235, an EX+++ example at $1,650, and a CLA'd RX-5 at $3,450. Unserviced or non-functional units go for less, but given the build quality and repairability, even a tired Bolex can often be brought back to life.

The most common issue reported is a dark viewfinder, usually from prism deterioration or misalignment. It is a known weakness over time, and the first thing to check on any example. Super 16 conversions are available from the factory and aftermarket. On the lens side, the 10mm Switar is particularly prized and highly sought after on the used market.

Market Value

┌──────────────────────────────────────────────────────────────────────────┐
│ BOLEX H16 REFLEX                                                Nov 2026 │
├──────────────────────────────────────────────────────────────────────────┤
│ High      $7,418                                  Latest            $845 │
│ Median    $1,296                                  Trend                — │
│ Low       $125                                    Volume          ~10/mo │
├──────────────────────────────────────────────────────────────────────────┤
│ $8,000 ┤                                                                 │
│        │                                               .                 │
│        │.                                                    .           │
│ $4,614 ┤                                       .    .              .     │
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│        │       .     .               ..    .     .        .    ...       │
│        │  .  ..  . .  . ..     .    . ...   ..    .  .        .          │
│   $100 ┤   ..   ...  .. .    . . ..  . ..  .. . ..  .          .    . . .│
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│    vol │▁ ▁▁▂▁▁▁▂▄▁▂ ▅▄ ▅▁   ▁ ▄ ▄▄ ▂▂█▄▂  ▄▂▁▁▁▂▂▁ ▂▁ ▁  ▁  ▁▁▄▂▁ ▁▂ ▁ ▁│
│        └─────────────────────────────────────────────────────────────────│
│         2026-01                      2026-04                      2026-08│
└──────────────────────────────────────────────────────────────────────────┘