Double CTO

Definition

The Double CTO is a color conversion filter that reduces the color temperature of light sources by two full Color Temperature Orange steps – from 5600K (daylight) to approximately 2900K (tungsten).

Practical Application

This lighting element is used in various professional scenarios:

• Color Correction: Adapting daylight sources to tungsten lighting setups
• Light Control: Achieving a warmer light mood without changing lamps
• Effect Design: Simulating tungsten light or warm sunlight
• Increased Efficiency: Avoiding color correction in post-production

Technical Details

Important technical features include:

• Density factor: -0.6 to -0.9 f-stops of light loss
• Available as sheet filters or gel filters for various fixtures
• Can be combined with other filters (ND, diffusion)
• Standard sizes: 12"x12", 20"x24", and rolls

Practical Tips

• Factor in an exposure correction of +1 f-stop
• Use heat-resistant variants for HMI lights
• Utilize a light meter for accurate light measurement after filtering
• Protect from direct sunlight and high temperatures

Professional Standards

In professional film and television production, standardized filters enable:

• Consistent color temperature across all light sources
• Quick adjustments without lamp changes
• Reduced post-production costs
• Consistent color rendition according to broadcast standards