Many digital cameras include an optical low-pass filter (OLPF) in front of the image sensor to blur some of the finest details before they reach the sensor. While it may seem counterintuitive to make an image softer, an OLPF helps prevent a very ugly digital artifact called moiré.
Cinematographer Dan Hopkins has been using a Panasonic Lumix full-frame mirrorless camera for videography for years and, until recently, mostly shot with the S1H, which includes an OLPF.
However, Hopkins added the excellent S5 IIX to his arsenal last year, a camera that lacks an OLPF. Since using the S5 IIX, he has come up against dreaded moiré artifacts, primarily on finely woven fabrics at weddings. While moiré is also an issue for still photography, addressing the issue in video is exponentially more challenging, if not outright impossible in some cases.
On the advice of a friend, Hopkins contacted Kolari, a company well known for its infrared camera conversions, filters, and now even sunglasses, to see if the company could help by adding an OLPF to the S5 IIX. After six months of development and some back and forth with Hopkins, Kolari developed an OLPF upgrade kit for Lumix full-frame cameras that does an excellent job preventing moiré at the source — the image sensor.
This additional filter comes with some downsides, including a slightly softer overall image and a white balance shift. Still, for videographers like Hopkins, these tradeoffs are well worth it to avoid the significant time sink that is trying to fix moiré during post. Hopkins is also developing a LUT to address the white balance shift, which will make the upgrade even more compelling for filmmakers, especially those working with multiple cameras that may not all have the Kolari OLPF upgrade installed.
Kolari’s OLPF upgrade is so good that it appears to do a better job at preventing moiré than the native OLPF in the S1H, which is quite an accomplishment. “The results are extremely impressive,” Hopkins explains.
“There is a very subtle loss in sharpness, which is just what comes with a proper OLPF. For us video shooters, it’s going to be really welcome with this sensor because it’s so sharp,” Hopkins says of the S5 II(X).
The Kolari OPLF/AA filter upgrade for Panasonic cameras is available for various Lumix cameras, including the S5 II(X), S1, and S1H. It is also available for the Sigma fp and even the Panasonic GH6, which is a Micro Four Thirds camera. The conversion service is $699 and takes two to three weeks. The complete details are available on Kolari’s website.