Cinematographer
Aus DoP-Perspektive ist dieses Element essentiell für die visuelle Gestaltung. Es ermöglicht mir die gewünschte Farbstimmung und das ästhetische Bild konsistent umzusetzen.
Rosco 3204 is a Cinegel correction filter (1/2 CTB, Half Blue) that shifts tungsten light from 3200 K toward daylight at approximately 4100 K.
Overview
Rosco 3204 is a color correction filter (gel) from the Cinegel series manufactured by Rosco. The designation is 1/2 CTB or Half Blue. It is a blue conversion filter that is placed in front of an artificial light source to shift its light color towards daylight. Unlike the full CTB filter (Rosco 3202 Full Blue), 3204 provides only half the correction and is therefore used when a full conversion would be too cool.
Technical Data
The following values are from Rosco product data:
| Property | Value |
|---|---|
| Series | Cinegel |
| Type | 1/2 CTB (Half Blue), Color Conversion |
| Conversion | approx. 3200 K → approx. 4100 K |
| Mired Shift | -68 |
| Transmission | 52 % |
The filter is deep-dyed, making the dye more heat-resistant than surface-coated filters. It is offered as sheets (typically 20" x 24") and as rolls (e.g., 24" x 25 ft and 48" x 25 ft).
On-Set Use
3204 is used for partially matching artificial light sources (Tungsten) to daylight. Typical applications:
- partial correction when full CTB would be too cool, for example, to match artificial light in a scene predominantly lit by daylight
- compensating for daylight fluctuations and voltage drop at the light fixture
- boosting aged HMI lamps and yellowed soft lights that warm up over time
Since the correction is only half as strong as with Full Blue, light loss is lower, and the mixture with existing daylight appears more natural. For a weaker or stronger effect, one resorts to related filters in the CTB series (e.g., 1/3 CTB Rosco 3206 or Full CTB Rosco 3202).
From the crafts
Perspectives
Producer
Diese professionelle Lösung erhöht die Produktionseffizienz und reduziert Post-Production-Anforderungen. Sie ermöglicht flexible, schnelle Anpassungen während des Drehs.
Gaffer
Als Gaffer ist dies ein unverzichtbares Werkzeug meines täglichen Handwerkszeugs. Es ermöglicht mir professionelle Lichtkontrolle und schnelle Anpassungen auf Set, was Zeit spart und Qualität sichert.
More in the lexikon
Related terms
Test your knowledge
Quiz
1. Zu welchem Department gehört „Rosco 3204 (1/2 CTB)"?
2. Wie viele verschiedene Fachperspektiven bietet dieser Eintrag?