ND2 Filter 67 mm
With the 67 mm ND2 Lens Filter, you can control the amount of light entering the lens and thereby also change the color and tones of your images. This is useful when shooting on larger apertures with the Petzval 55 especially in sunny conditions – Using the ND filter, you can reduce the amount of light coming into the lens, whilst still keeping the strong Petzval swirly bokeh effect.
Color Filter Red 67 mm
For black and white photography, colored filters are used to bring out the different shades of grey and get your desired contrast of your photos. Greatly increases contrast, turns blue sky into almost black, darkens foliage & reduces haze.