Leica Yellow Filter Silver Frame This filter slightly increases the contrast in B/W (monochrome) photography. The strength of the contrast is: Yellow → Orange → Red This is the weakest effect for contrast enhancement. For those who shoot monochrome with film, yellow is probably a good everyday filter. Scratches and wiping marks are visible on the glass surface. I don't think it will affect the actual images that much (personally). I don't think it will produce a foggy effect. There are scratches, so please refrain from purchasing if you are extremely concerned. E39 size Yellow Made by Leitz With a clear case - Model: E39 YELLOW - Brand: Leitz - Manufacturer: Ernst Leitz GmbH Wetzlar - Color: Yellow - Case: With a clear case