"Attaching Your Filters"
Not all lenses are designed with standard filter accessory screw in thread sizes. For these lenses, many of which are very popular, the way to mount a filter is via an adapter ring. A main feature of adapter rings is that you can utilize one size filter with a number of different sized lenses via different adapter rings.
· An Adapter ring consists of two parts: an adapter ring and a retaining ring. The non-threaded filter is held in place between the two as you screw the retaining ring into the adapter ring. The adapter ring is than screwed directly into the lens or is mounted to the outside diameter of the lens barrel via a setscrew lock ring adapter.
· To stack non-threaded filters, a second retaining ring is required to be threaded into the first retaining ring and the second filter is than held in place between the two.
· Adapter rings contain two measuring specifications: 1) the direct screw in size to the lens such as 86mm, 95Cmm, etc / or outside lens diameter to mount a setscrew lock ring and 2) the size of the filter that the adapter wil1 accommodate.
Example: 105Cmm-4-1/2'' screws directly into a lens requiring a 105Cmm accessory size and accepts 4-1/2"round size non-threaded filters.
Example: 124SSLR-138mm features an adapter that set screws over a lens barrel (SSLR) with an outside diameter of 124mm and accepts 138mm round non-threaded filters.
· Larger or smaller filters than the designated filter size may also be utilized on lenses via a Step Up or Step Down ring. To determine which type ring you need, start with the lens accessory size of your lens and convert it to the desired filter size needed to be used.
Example: A lens featuring a 62mm accessory size with the need to mount a 77mm filter would require a 62mm-77mm Step Up ring.
Example: A lens requiring a 58mm accessory size with the need to mount a 52mm filter would require a 58mm-52mm Step Down ring. It is not suggested to utilize a Step Down ring more than a two-size difference between the lens and filter otherwise lens vignetting may result.