Cinematographer
Die Perforation bestimmt, wie präzise der Film registriert. BH für Kamera, KS für Print – das richtige Perf-Format ist entscheidend für scharfe, stabile Bilder.
Standardized holes along film edges that engage with sprockets for precise mechanical transport through cameras, projectors, and processing equipment – various perforation types (BH, KS, DH) suit different applications and affect image stability.
What is Film Perforation?
Film perforation refers to the standardized holes on the edge of the film strip that enable mechanical transport through cameras, projectors, and lab equipment. These precise cutouts engage with sprockets and ensure frame-accurate positioning.
Perforation Types
| Type | Description |
|---|---|
| BH (Bell & Howell) | Camera Negative |
| KS (Kodak Standard) | Positive/Prints |
| DH (Dubray-Howell) | Positive Hybrid |
| CS (Cinemascope) | Anamorphic |
BH vs. KS
| Aspect | BH | KS |
|---|---|---|
| Shape | Rectangular with rounded corners | Rectangular |
| Usage | Camera Negative | Projection/Print |
| Precision | Highest | Standard |
| Reason | Registration | Durability |
Perforation Pitch
| Term | Description |
|---|---|
| Short Pitch | Negative (0.1866") |
| Long Pitch | Print (0.1870") |
| Difference | Compensate for shrinkage |
| Importance | Registration |
35mm Perforation
| Standard | Perfs per Frame |
|---|---|
| 4-Perf | Standard Academy |
| 3-Perf | TV Production, efficient |
| 2-Perf | Techniscope |
| 8-Perf | VistaVision |
16mm Perforation
| Type | Description |
|---|---|
| Double Perf | Both sides |
| Single Perf | One side (for sound) |
| Position | Between frames |
65/70mm
| Aspect | Description |
|---|---|
| Perfs | 5 per frame |
| Pitch | 0.200" |
| Stability | Very high |
| IMAX | 15 perfs horizontally |
Registration
| Element | Function |
|---|---|
| Precision | Micron range |
| Pins | Engage in perforations |
| Steadiness | Image stability |
| Quality | Dependent on sharpness |
Perf Damage
| Problem | Cause |
|---|---|
| Torn Perfs | Over-tensioning |
| Stretched | Mechanical stress |
| Worn | Frequent projection |
| Damaged | Poor handling |
Consequences
| Damage | Result |
|---|---|
| Uneven | Image jitter |
| Torn out | Transport problems |
| Worn out | Inaccurate registration |
| Scratched | Visible artifacts |
Sprocket Mechanism
| Element | Function |
|---|---|
| Teeth | Engage in perfs |
| Pressure | Hold film |
| Timing | Synchronized |
| Pulldown | Frame advance |
Historical Development
| Year | Development |
|---|---|
| 1889 | Edison 4-perf |
| 1909 | Standardization |
| 1930s | Sound adaptations |
| 1950s | Widescreen formats |
Lab Processing
| Aspect | Description |
|---|---|
| Transport | Via perforations |
| Registration | Pin-precise |
| Scanning | Perf detection |
| Synchronization | Sound/image |
Scanning and Perfs
| Element | Significance |
|---|---|
| Detection | Automatic |
| Alignment | Locate frame |
| Overscan | Perfs visible |
| Cropping | Remove perfs |
Perf Orientation
| Term | Description |
|---|---|
| Emulsion In | Emulsion layer inward |
| Emulsion Out | Emulsion layer outward |
| A/B Wind | Winding direction |
| Importance | Lab compatibility |
Sound Track Area
| Format | Perf Influence |
|---|---|
| Optical | Adjacent to perfs |
| Magnetic | Between perfs |
| Digital | Within perf area |
| DTS | Adjacent to perfs |
Best Practices
| Practice | Reason |
|---|---|
| Correct Specification | Compatibility |
| Careful Handling | No damage |
| Keep Clean | No dust in perfs |
| Documentation | Note perf type |
Today
Film perforation may seem like an invisible detail, but these precise holes are fundamental to the entire analog film ecosystem. They enable the mechanical precision that has made motion pictures possible for over 100 years – a standard that connects cameras, labs, and projectors worldwide.
From the crafts
Perspectives
Director
Perforationen sind die unsichtbaren Helfer – sie ermöglichen den gleichmäßigen Filmtransport. Probleme zeigen sich als Bildzittern oder Unschärfe.
Producer
Perforation-Inkompatibilität kann teuer werden. Kamera-Negativ mit einem Perf-Typ, Kopierwerk erwartet anderen – solche Fehler kosten Material und Zeit.
More in the lexikon
Related terms
Test your knowledge
Quiz
1. Zu welchem Department gehört „Filmperforation / Perforierung / Transportlöcher"?
2. Wie viele verschiedene Fachperspektiven bietet dieser Eintrag?