Yes, the RFS can be used with step up rings but we designed the RFS+ to replace them. With the RFS+ you can step up from any lens diameter to a larger filter size and still have all the benefits of the RFS.
We have tested the RFS to perform without vignetting up to 18m on prime lenses and up to 30mm on zoom lenses. If you are trying to go wider than this we recommend upgrading your RFS to the RFS+ and choosing a size 10+mm wider. For example. If you are shooting with the Tamron 28-75mm which has a 67mm filter diameter; we recommend upgrading to a RFS+ 67/77.
Lens caps are compatible with the RFS and your filters so feel free to keep your gear protected when not in use. When the device is open we find that it keeps the filter out of the way and collects less dirt or dust than it would in your pocket or bag.
If you want to change your pledge at anytime please visit the project page and click the “Manage your pledge" button that appears next to your pledge amount and then select "Change your pledge" on the following page.
The RFS+ allows you to step-up to a larger filter and still retain all the features of the RFS. For example: if your lens requires a 67mm filter, the RFS+ could install on the 67mm lens and adapt to a 77mm filter.
The coating is known as a MIL-A-8625 Type II Class 2 sulfuric anodize and helps withstand corrosion, fatigue, and damage. It’s used in military applications, architectural materials, and sporting goods.