Marumi M100 100mm Magnetic Filter Holder
£142.69/$149.95 Marumi’s use of magnets in its M100 holder means that it’s very quick and easy to swap between different filters www. marumi - global . com
“The magnets are strong, but it’s still fairly easy to push a filter up or down if you need to adjust the position of a graduation”
It may not be the best-known filter manufacturer, but Marumi has been in the optics industry for over 85 years. It produces a huge range of filters with screw-in, round magnetic and square filter options. The company’s square and rectangular filters are produced in collaboration with H&Y and feature an H&Y frame that allows them to be mounted in the Marumi M100 100mm Magnetic Filter Holder.
As well as the standard graduated neutral density (ND) filters, Marumi offers more exotic options like reverse graduated ND and centre graduated ND filters, which can be useful when photographing sunset or sunrise. Marumi sells the 100mm Magnetic Filter Holder (M100) filter by itself, but the Circular Polariser for M100 is specifically designed for use with it and the holder, and its adapter has a dedicated section for it. Similarly, it needs filters that are in a frame and designed to mount by magnetic attraction.
Key features
Marumi supplies the M100 100mm Magnetic Filter Holder with 72mm, 77mm and 82mm adapter rings, but the holder can be mounted on lenses with other filter threads via a step ring (not included). The adapter rings have a wide, smooth rim that enables them to be threaded easily onto a lens, and a slightly recessed knurled section that can rotate separately from the outer part.
Marumi’s Circular Polariser fits within the raised edge of an adapter ring. Because the Marumi holder uses magnets to hold square and rectangular filters, there are no guide rails or filter slots to thread the filters into. This means that the holder is slimmer than many others, but it can only be used with 100mm-type filters that are mounted in a frame that is subject to magnetic attraction.
A cog in the bottom of the holder knits with the knurled rim of the Marumi adapter rings to enable the Circular Polariser to be rotated without touching the filter itself. It’s good to see a light seal around the aperture in the Marumi 100mm Magnetic Filter Holder, as this prevents light leaks during long exposures.
Build and handling
Marumi (or possibly H&Y) makes the filter holder from aluminium and it has a fairly chunky main section that gives it a very solid feel overall. The filter holder is held on the adapter ring by two screw-down retainers, one on either side of the back of the retainer. These prove very tricky to use when the adapter ring is on the lens, and instead it’s better to mount the adapter ring on the holder and then screw the whole thing onto the lens.
Once an adapter ring has been mounted on the holder, the polariser can be moved into position. Without an adapter ring, the polariser is too small to be held by the holder. Fitting the polariser reveals a little surprise: it isn’t magnetic. Fortunately, when it’s screwed into the correct position, the polariser is held pretty tightly, but it doesn’t always slip straight into the right place and it’s a bit fiddly. Consequently, it’s important to be very careful with the fit, especially if the lens is tipped forwards and no other filters are in use. If a square or rectangular filter is in use, it will keep the polariser in the holder even if it isn’t screwed in properly.
The M100 holder is designed to be used with Marumi’s filters, which feature a magnetic frame made by H&Y. These are pulled magnetically onto the holder and are held securely. The magnetic