MARUMI Magnetic Square Filter System – Attaching ND and GND Filters Made Easy

by Jakub HanNovember 22^nd, 2018

MARUMI is a Japanese company known as a classic circular filters manufacturer. At Inter BEE 2018 they presented a new interesting product which is a bit different. It is called MARUMI magnetic square filter system and it makes it possible to easily mount (or even stack) square ND or GND filters in front of the lens. We talked to mister Akihiko Sato from MARUMI about the new system.

Heart of the MARUMI magnetic square filter system is the M100 magnetic attachment adapter (filter holder) which makes it possible to quickly attach or detach 100mm square filters to the front of basically any photographic lens. The M100 adapter is made out of aluminium and features ultra slim design of just 10mm. That enables mounting the filters as close to the front element of the lens as possible to prevent vignetting on wide angle lenses. MARUMI claims there is no vignetting even with 16mm focal lenght (full frame) lenses.

Installation of the system. Source: MARUMI

The filters itself have a metal border which even allows stacking more filters on each other in case a combination of more filters is needed. Furthermore there is a thin layer of foam around the opening on the magnetic filter holder to protect attached filter and prevent light leaking.

There are multiple size holder rings included in the package – 82mm, 77mm and 72mm. For mounting the filter holder on smaller diameter lenses, additional step-up rings need to be screwed on the lens. The filter holder can rotate independently.

MARUMI offers a variety of filters for their magnetic system. All of them are made in Japan and their low-reflection anti-scratch surface is anti-static and water/oil repellent. The line-up includes:

• ND filters (100mm x 100mm). Available as ND4, ND8, ND16, ND32, ND64, ND500, ND1000,ND4000 and ND32000.
• Graduated ND filters (100mm x 150mm for up/down movement). GND filters are available with three different gradient versions. Soft gradient (for scenes without clear horizon line), hard gradient (for scenes with clear horizon line) and reverse gradient (for sunrise or sunset scenes). All of them with GND4, GND8 and GND16 strengths. GND filters adopt high definition Schott B270 glass and have double-side coating for low reflection and easy maintenance.
• Circular PL filters. These circular filters can be attached before mounting the magnetic holder.

Transmittance graphs for the filters. Source: MARUMI

It seems to me this filter system could suit perfectly the needs of frequent timelapse shooters for example. In terms of pricing, the M100 filter holder will sell for $120,- USD, ND filters for $190,- USD and GND filters for $200,- USD.

What do you think of the MARUMI magnetic square filter system? Do you see the need for such a product? Let us know in the comments underneath the article.