My anticipation for the Panasonic Lumix S1R has been building, having first encountered it as a non-working prototype in last year's Photokina show before trying a working model two months ago at the CP+ show.

This is the first full-frame mirrorless camera from Panasonic. The review unit is the 47.3-megapixel high-end model. There is another variant - the 24.2-megapixel Lumix S1.

The S1 is the more video-centric modelwith a no-crop 4K video output, while the S1R is the higher-resolutionphoto-centric model.

Both models are identical in looks,withaweather-sealed magnesium-alloy body that feels rock solid and is fantastic to hold. The huge ergonomic front grip lets you holdthe camera firmly and comfortably while allowing easy access to all the buttons and dials.

The button layout is amongthe most well thought-outlayouts I have seen in years of reviewing cameras.

There is a command dial on top of the grip and another command dial on the top right for quick change of settings. Beside the command dial is a small monochrome display that shows the most important information, such as aperture size, shutter speed and ISO. In front of the display and behind the shutter release button are three quick buttons to access white balance, ISO and exposure compensation.

The right rear of the cameras has an array of buttons, including ones for Display, Quick Function and Back, as well as a directional pad and a wheel dial that are easily accessible with the right thumb. A mini-joystick near the thumb rest lets you adjust the autofocusing (AF) point quickly.

The mode dial is on the top left, with the left side of the camera having compartments for the audio jacks as well as a HDMI port and a USB-C port that can be used for charging.

The compartment on the right houses two memory card slots for an XQD card and an SD card. I like that this camera still allows the use of the more affordable SD card.

Both the S1 and S1R feature the highest-resolution electronic viewfinder (EVF) in the market, with a resolution of 5.76 million dots and a 120Hz refresh rate. Using the EVF to compose pictures is almost like looking through an optical viewfinder.

Operation wise, the S1R is pretty swift. It starts up in 0.9 second and shuts down in 1.1 seconds. These timings are faster than most mirrorless cameras' power-up and shut-down timings of two seconds each.

Using an XQD card with a writing speed rated at 440MB per second, the S1R was able to shoot 42 RAW images in 4.2 seconds before the buffer ran out. Amazing speed for a high-resolution full-frame mirrorless camera.

Using the Panasonic 24-105 f/4mm L-mount lens, the S1R's AF is instantaneous under bright sunlight. Under dim lighting conditions, it was able to achieve focus lock in around a second most of the time. Further aiding focusing is a feature calledThe Eye AF - activate it and the camera willhunt a subject's eye with utmost precision and speed. Great for shooting portraits when you need the eyes to be sharp.

Image quality is impressive, to say the least.The extremely sharp details that this camera produces are truly stunning.

Image noise performance is superb as well. There are no visible noise artefacts until ISO 3,200. At ISO 6,400, noise artefacts start to appear but with only slight detail loss to images. In fact, I can make out the details of the fur of a cat that I photographed late at night at this setting. Only at ISO 12,800 and above will you notice significant loss in detail and sharpness.

On the downside, the S1R's robust build means it is considerably larger and heavier - it weighsover 1kg - than competitors like the Nikon Z7 (675g) and Canon EOS R (660g).

Itsbattery life is also mediocre. It is rated at 360 still images on a full charge. In my tests, I found it was left with 50 per cent charge after shooting only 200 still images. I recommend getting another battery if you want todo full-day shoots.

But the biggest bugbear is its price tag. At $5,199 (body only), the S1R is more expensive than the Canon EOS R with a RF 24-105mm f/4 kit lens ($5,098) and the Sony a7R III ($4,699, body only).

FOR

- Excellent image quality

- Sturdy and weather-sealed body

- Dual memory card slots in different formats

AGAINST

- Expensive

- Larger and heavier than its competitors

- Mediocre battery life

SPECS

PRICE: $5,199 (body only)

IMAGE SENSOR: 47.3-megapixel MOS full-frame

DISPLAY: 3.2-inch tiltable touchscreen LCD with 2,100,000 dots; Electronic viewfinder with 5,760,000 dots

SENSITIVITY: ISO 50 to 51,200

SHOOTING SPEED: Up to 9 frames per second

CONNECTIVITY: Bluetooth, Wi-Fi

WEIGHT: 1,016g (body with battery and SD card)

RATING

FEATURES: 5/5

DESIGN: 5/5

PERFORMANCE: 5/5

BATTERY LIFE: 3/5

VALUE FOR MONEY: 3.5/5

OVERALL: 4/5

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