UV filter - 30mm to 62mm

The purpose of the Ultraviolet filter is to block UV rays, which softens the atmospheric haze. This tends to protect outdoor images from the harmful effects of these rays.

It is also advisable to equip all your lenses with it to protect your front optics from shocks and especially from dust and scratches...

You can find out the filter holder 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...