The Cokin A727 Yellow CC (CC40Y) camera filter is a color correction filter for photographic applications, specifically the Yellow CC40Y variant, which allows for precise color temperature adjustment. This filter belongs to the Cokin A727 series, compatible with lens systems that use the A727 filter holder, and measures approximately 72 mm in diameter with a standard thickness of 2-3 mm, weighing around 15-20 g. Made from optical glass with multi-layer coating, it offers high light transmission with minimal reflection and ghosting. The Yellow CC40Y filter absorbs blue light wavelengths and increases the color temperature by about 4000-4500 K, making it suitable for correcting cool lighting conditions or for specific atmospheric effects. It maintains color consistency in the visible spectrum with minimal color shift and has a neutral density effect of about 0.3-0.5 stops. The filter frame is made of anodized aluminum with precise threading for a secure fit, and the optical surfaces are scratch-resistant coated. Compatible with digital and film cameras, it preserves image sharpness with minimal resolution loss and is particularly suitable for landscape, portrait, and architectural photography, where precise color control is required. The Cokin A727 system allows for quick filter changes and stacking with other filters in the series. Storage and handling should follow standard maintenance procedures for photographic filters to maintain optical quality.