Weather-Sealed Mirrorless Differences

Weather-sealed mirrorless cameras offer protection against the elements to varying degrees. They are all dustproof and moisture-resistant. They can also handle splashing from any direction, so will keep working in rain or snow, as long as a weather-sealed lens is attached. This is crucial since a weatherpoof camera with a lens that is not, will not be weatherpoof because water and dust can enter through the lens-mount.

Weather Resistance

Cold is a problem for electronics in general and mirrorless cameras are not exempted. All digital cameras remain fully functional at temperatures above 0°C (32°F) although battery-life gets shorter as temperatures drop. Among weather-sealed mirrorless cameras, all but those from Panasonic, are freezeproof down to -10°C (14°F). Those freezeproof models will keep operating reliably below freezing. Below their respective minimal temperature, a digital camera does not simply stop working. Instead, battery-life becomes very limited and displays (EVF & LCD) which are generally made of liquid-crystals become unresponsive. Too much time spent below freezing or -10°C for freezeproof cameras, may eventually cause internal damage to the battery. Generally though, digital cameras mostly return to normal once warmed up.

Image Sensors

Mirrorless cameras compared here do not all have the same sensor-size. Within a generation, larger sensors nearly always produce higher image-quality than smaller ones. This is simply a matter of physics since larger sensors receive more light. They are therefore more sensitive and capable of capturing more dynamic-range.

There are currently 3 sensor sizes used by these 7 contenders. Fuji cameras offer the largest sensors with a 3:2 aspect-ratio and 1.5X crop-factor. Olympus and Panasonic mirrorless share the Micro Four-Thirds platform which uses a 4:3 aspect-ratio sensor with 2X crop-factor while the Nikon 1 system is built around a 3:2 aspect-ratio 1" sensor having a 2.7X crop-factor.

On the right, you can see the physical size of all these sensors superimposed. While their size looks similar linearly, what matter is the surface area. A Four-Thirds sensor has 93% more area than a 1" one and an APS-C senor has 64% more.

The most common resolution among these cameras is 16 megapixels. The Panasonic GX8 is the only model to offer a higher resolution of 20 megapixels, while the Nikon 1 AW1 has a slightly lower-resolution of 14 megapixels. Possible print-sizes are therefore similar before image-noise starts affecting details.

Image Stabilization

The third most significant difference between these cameras is how they are stabilized. Fuji and Nikon cameras entirely rely on optical image-stabilization performed by the lens. This is rather restrictive since there are currently only two stabilized weatherproof lenses for the Fuji X-mount and none at all for the Nikon 1-mount.

Olympus took the opposite approach, producing mirrorless cameras with built-in image-stabilization, thus automatically granting stabilization to all weather-sealed M.Zuiko. With up to 5-axis of stabilization, OM-D cameras can effectively stabilize any lens. This works regardless of brand and even through a lens adapter for legacy mounts, including weatherproof Zuiko lenses using a weatherproof adapter. No other such adapter is weather-sealed at this time.

Interestingly, Panasonic took both approaches at once. Their GH4 does not offer built-in stabilization, while their recently-reviewed GX8 does. Not only does the Panasonic GX8 supports stabilized lenses too, it also can combine sensor-shift and optical-stabilization for improved efficiency. This also allows the GX8 to take full advantage of Olympus Micro Four-Thirds lenses since they are all compatible across the system.

NOTE All links above perform a live-search over Neocamera's lens database, so may show more results as new offerings get released.

Viewfinder & Hot-Shoe

This major difference is the simplest to explain. The Nikon 1 AW1 neither has an EVF nor a hot-shoe. Each other mirrorless featured in this article has a high-resolution 2.4 megapixels EVF with Eye-Start sensor and a standard hot-shoe. All these viewfinders show 100% coverage and are relatively large, being either 0.5" or 0.44" units and having magnification between 0.67X and 0.77X. These two features are crucial for professional use.

Table 3 - Weather-Sealed Mirrorless Major Differences
Camera	Fuji X-T1 [Graphite]	Nikon 1 AW	Olympus E-M1	Olympus E-M5 Mark II	Panasonic GH4	Panasonic GX8
Weather Protection	Splashproof Freezeproof	Waterproof Freezeproof	Splashproof Freezeproof	Splashproof Freezeproof	Splashproof	Splashproof
Sensor Size FLM	APS-C 1.5X	1" 2.7X	Four-Thirds 2X	Four-Thirds 2X	Four-Thirds 2X	Four-Thirds 2X
Resolution	16 MP	14 MP	16 MP	16 MP	16 MP	20 MP
Max ISO	51200	6400	25600	25600	25600	25600
Stabilization	No	No	5-Axis	5-Axis	No	Dual
Autofocus	49-Point Phase-Detect	135-Point Phase-Detect	37-Point Phase-Detect	800-Point Contrast-Detect	49-Point Contrast-Detect	49-Point Contrast-Detect
EVF Size Magnification	0.5" 0.77X	No	0.5" 0.74X	0.5" 0.74X	0.5" 0.67X	0.44" 0.77X
Hot-Shoe	Yes	No	Yes	Yes	Yes	Yes
Video	1080p	1080p	1080p	1080p	Cinema 4K	4K

Continue to page 3 to read about secondary differences between these weatherproof mirrorless cameras.