IR Pass 685nm planetary filter

Antlia IR Pass 685nm filter

The Antlia IR Pass 685nm filter is designed for advanced planetary imaging. By allowing only wavelengths longer than 685 nm to pass through, it significantly reduces the effect of atmospheric turbulence (seeing), resulting in sharper, higher-contrast images. This filter is ideal for photographing Mars, Jupiter, Saturn, and other planets, even in broad daylight, thanks to its darkened sky background.

Key features

• Selective transmission of infrared light beyond 685 nm
• High-quality Schott optical glass
• Double-sided polished optical surface for λ/4 accuracy
• Surface quality: 60/40 according to MIL-O-13830
• Parallelism less than 30 arcsec
• Ultra-thin sensor to maximize the effective aperture and minimize vignetting
• Durable black anodized finish with resistant laser engraving

Ideal applications

• Infrared planetary imaging of Mars, Jupiter, Saturn
• Daytime planetary photography (sky darkened by IR filtering)
• Combine with RGB and U-Venus filters to enhance image sharpness

Technical specifications

• Size: 1.25″ mounted (M28.5×0.6)
• Thickness: 2mm ± 0.05mm
• Substrate: Schott optical glass
• Surface polished on both sides for optimum flatness

Bracket design

• Ultra-thin frame to reduce vignetting
• Anti-glare black anodized finish
• Permanent laser engraving on the frame

Cautions and warnings

• Do not use for solar observation.
• Do not use for direct visual observation.
• Use reserved exclusively for planetary photography.
• Strictly observe the safety instructions to avoid serious eye damage.