Blue Filter - 49mm to 55mm

The Blue filter is used in black and white film photography to isolate part of the spectrum and modify your image.

It is recommended for panchromatic films.

This filter lets blue light pass through, brightening blue skies and darkening the green of vegetation. It considerably increases contrast.

You can find out the filter thread size of your lens by measuring the internal thread; it does not correspond at all to the focal length: for example, a 50mm 1.8 lens can have a 49, 52 or 55mm thread...