Follow this newly discovered method of simulating a polarizing filter with Adobe Photoshop that’s faster, easier, and more effective. Considered the most useful filter in Photography, a polarizing filter makes almost any image look better by absorbing glare to reduce or eliminate reflections and darken skies.
For most wide angle lenses (wider than 40mm), with and without B+W standard circular polarizer filter test results are available in the (look for the last focal length option).This tool allows comparison to determine if the standard B+W filter ring depth causes light to be blocked from reaching the sensor – mechanical vignetting.
Lastly, we wanted to see how good the provided glass polarizing filter is when compared to a high-end polarizing filter from B+W, specifically the , which by itself costs around $135. After going back and forth to measure sharpness between these filters, we could not spot any noticeable differences in performance – the difference was less than 1-2%, which falls into margin of error. So the NiSi filter seems to be as good as the B+W filter in terms of not impacting image sharpness.
Linear polarizing filters were the first types to be used in photography and can still be used for non-reflex and older SLR cameras. However, cameras with through-the-lens metering and autofocusing systems - that is, all modern SLR and DSLR - rely on optical elements that pass linearly polarized light. If light entering the camera is already linearly polarized, it can upset the exposure or autofocus systems. Circular polarizing filters cut out linearly polarized light and so can be used to darken skies or remove reflections, but the circular polarized light it passes does not impair through-the-lens systems.