Mitchell BNCR

mitchell mitchell bnc arri bl panaflex gold panavision

The reflex version of the legendary BNC (1967) – finally allowing view through the lens during recording. The last major Mitchell innovation before Panavision took over the company and developed the Panaflex.

What is the Mitchell BNCR?

The Mitchell BNCR (1967) – the "R" stands for Reflex – was the modernized version of the legendary BNC with a reflex viewfinder. This last major innovation from Mitchell enabled viewing through the taking lens during recording for the first time and became the technical foundation for the later Panavision Panaflex.

Technical Specifications

Feature	Value
Format	35mm (4-perf)
Weight	~38 kg (complete)
Shutter	Reflex, 175°
Frame Rate	4–36 fps
Viewfinder	Reflex
Mount	BNCR Mount (later PL base)
Magazines	120m / 300m / 600m

Key Features

Reflex Viewfinder – Viewing through the lens
Self-blimped – Quiet like the BNC
Dual-Pin Registration – Legendary steadiness
BNCR Mount – Modernized bayonet
Compatibility – BNC magazines usable
VFX Precision – Like the original BNC

BNC vs. BNCR

Feature	BNC (1932)	BNCR (1967)
Viewfinder	Rack-over	Reflex
Framing	Before shooting	During shooting
Focusing	Focus measurement	Live through lens
Weight	~40 kg	~38 kg
Noise	Quiet	Quiet
Picture Stability	Excellent	Excellent

The Reflex Revolution

The Problem with the BNC

Rack-over system time-consuming
No live framing possible
Focus had to be measured
Parallax issues with close-ups

The BNCR Solution

BNC (RACK-OVER): BNCR (REFLEX):

[Viewfinder] [Lens] [Mirror] → [Viewfinder]
 | | |
 Eye Film [Lens]
 |
 Film

180° mirror directs light to the viewfinder
During shutter opening: light to film
During shutter closing: light to viewfinder
Live image during the entire recording

Notable Films

Film	Year	DP	Significance
2001: A Space Odyssey	1968	Geoffrey Unsworth	VFX Masterpiece
Butch Cassidy and the Sundance Kid	1969	Conrad Hall	Oscar for Cinematography
The Godfather	1972	Gordon Willis	(partially)
Chinatown	1974	John A. Alonzo	Noir Revival
One Flew Over the Cuckoo's Nest	1975	Haskell Wexler	Oscar for Film

2001: A Space Odyssey (1968)

The BNCR played a key role in Kubrick's masterpiece:

Why BNCR?

Excellent picture stability – Critical for VFX
Reflex viewfinder – Precise framing
Dual-pin registration – Multiple exposures
Reliability – Long production time

VFX Work

Front projection
Matte paintings
Model shots
Slit-scan (Stargate sequence)

The BNCR Mount

The BNCR Mount became an important standard:

Aspect	Details
Design	Modernized bayonet
Flange depth	Identical to later PL
Influence	Basis for PL mount development
Lenses	Zeiss, Cooke, etc.

Significance for Panavision

BNCR mount design adopted
Further developed into Panaflex mount
Compatibility line continued

The Panavision Acquisition (1968)

Timeline

Year	Event
1967	BNCR Market Launch
1968	Panavision buys Mitchell
1972	Panaflex (based on BNCR)
1970s	Mitchell production ceased

What Panavision Acquired

Mitchell precision manufacturing
BNCR technology
Employee know-how
Mount design (for Panaflex)

BNCR vs. Competition (1967)

Camera	Weight	Viewfinder	Noise
Mitchell BNCR	~38 kg	Reflex	Quiet
Mitchell BNC	~40 kg	Rack-over	Quiet
ARRI BL	~7 kg	Reflex	Quiet
Arriflex 35 IIC	~5 kg	Reflex	Loud
Eclair Cameflex	~4 kg	Reflex	Moderate