The diffusion filter is a tool used to maintain the sharpness of an image while increasing its contrast by 26%. It creates a glowing effect around shiny objects, brightening up shadows and allowing for unique effects. Diffusion filters are mainly used in film production, but photographers can also benefit from their use. There are several types of diffusion filters, each with its own properties and effects.
They are especially useful in night photography, when the contrast between light and shadow is too great for the camera to capture evenly. The filter disperses light over a larger area, creating a fog-like effect. This allows for better control in post-processing and complements image noise. Compared to other filters, such as the K&F filter, diffusion filters are more limited to point light sources and do not scatter throughout the frame.
The effects they produce can be similar to those achieved with the Orton effect, but the main difference is that the Orton effect affects both light and dark parts of the frame equally, while diffusion filters emphasize the brightest parts. When using a diffusion filter with a long focal length, it is advantageous to reduce the level of diffusion. Glimmerglass filters tend to retain more of the character and quality of the lens, while Softnet filters mimic the use of placing a net behind the lens. These filters add brightness to bright parts of the image, similar to lenses with an undercorrected spherical aberration.Filter number 1 should produce a strong effect when used with light, as it is easy to see in scenes with many bright light sources in the background. However, when shooting at a wide angle, this filter can be too strong for small details.
It can soften the frame, add thick fog, and keep sharpness at a high level. This type of diffusing lens filter reduces contrast during transition to the shadow zone while maintaining clear sharpness throughout the photo. Diffusion filters are incredibly useful tools for photographers and filmmakers alike. They can be used to create unique effects that would otherwise be impossible to achieve without them. They also help reduce contrast in night photography and add brightness to bright parts of an image. When using a diffusion filter with a long focal length, it is important to reduce its level of diffusion in order to retain more of the character and quality of the lens.