NiSi’s Latest Variable ND Filter Avoids the X-Effect Problem

NiSi has announced a new variable ND filter called the Pro Nano 1.5-5-stop Enhance ND-Vario. One of the filter’s features is that it says has no dreaded X-effect.

Variable ND filters are made by stacking polarizing filters, which are then turned to produce different intensities. One common weakness is that at their darkest settings, you will often see a black X appearing in the image like this:

Here’s a video comparison showing a filter that exhibits the X-Effect and this NiSi filter that doesn’t:

NiSi claims to have conquered this problem, although the company hasn’t revealed any details about how it managed to do so.

The filter will reduce exposure by 1.5 to 5 stops and is also said to have “enhanced color” compared to other brands while still “retaining a neutral cast.”

Here’s a 1-minute video shows the effect of the filter on sharpness and color, as well as the above comparison of the (lack of) X-effect on the new variable filter versus a different brand.

The NiSi Pro Nano 1.5-5-stop Enhance ND-Vario has a nano coating and an ultra-slim frame. The filter is available in 67mm, 72mm, 77mm, 82mm, and 95mm threads.

Here’s a 4-minute review which looks at the raw files produced using the filter:

NiSi has yet to release information on pricing or availability, but this will no doubt follow shortly.

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