Recently I had the opportunity to use a new product from Breakthrough Photography. They have a new ring which can use not only their square and rectangular holders but also a magnetic circular polarizer. Check out the video!
If there is one filter that is a must have for all of my lenses it is a Circular Polarizer. The effects of most other filters can be quickly recreated in post. There is still a need for an neutral density filter and to some extent a graduated ND filter. The latter can be reproduced in post but requires the blending of exposures through HDR or more manual methods.
This is a question I have been asked multiple times. So, I thought I would put together a short video to show you how you can use a circular polarizer with a filter holder system. All of these are Breakthrough Photography Filters.