Sony’s popular RX100 series of advanced compacts hits its fourth generation with the RX100 IV, an upscale version of the RX100 III that doesn’t shine quite as brightly as its sibling the RX10 II. Though it shares most of the same updates, it still faces some competition from the Panasonic Lumix LX100.
The RX100 IV is expected to ship in July for $1,000; UK and Australian pricing haven’t yet surfaced as I write this, but that converts to about £645 and almost AU$1,300.
- Sensor. The RX100 IV offers a 1-inch, 20-megapixel sensor like the RX100 III, but it uses a different technology dubbed “stacked CMOS sensor” and branded Exmor RS. Although it first appeared two years ago, the RX100 IV and RX10 II are the initial cameras to use it. The Exmor RS is a reframing of the backside illuminated (BSI) design commonly found in point-and-shoots and phone cameras; typical BSI designs have the light-sensing pixels on the top layer along with the circuits that process the image data, with a substrate in a layer below. For the stacked sensor, light receptors live on their own layer while the circuits occupy the layer beneath. That means a given size sensor can have potentially bigger and more sensitive pixels. Another change in the sensor is the use of high-speed processing and additional memory below the circuitry for passing the image data along to the next stop in the process a lot faster. Sony also claims that this speed improvement defeats the jello and leaning verticals that you see during fast horizontal movement.
- High frame rates and 4K. The ability to shoot at an exceptionally fast rate lets you create slow-motion video; slo-mo is just playing back a high frame-rate capture in normal time. The faster sensor enables whizzy features like 960 frames per second shooting for 2 seconds, which allows you to produce slow-motion video clips (also 240fps and 480fps for longer durations), as well as 16fps continuous-shooting speeds with fixed exposure (the real rate is 5.5fps). Note that the RX100 IV actually has a faster continuous-shooting rate than the more expensive RX10 II; the latter has a much larger lens and a bigger shutter to move. It also records 4K (QFHD 3,840×2,160 pixels) but it’s limited to 5-minute clips. It can prerecord — buffer frames — so that it doesn’t matter if you juuust miss the decisive moment.
- High shutter speed. The electronic shutter goes up to 1/32,000 second, which sounds a little more impressive than one stop above the 1/16,000 second most cameras in its class support. However, it does mean you have a little extra exposure wiggle room in extremely bright conditions.
The slow-motion capability is neat — the LX100 can only do 40fps — but the new sensor will have to deliver better quality than the larger Four Thirds sensor and slightly longer and faster lens in the cheaper LX100. True, the RX100 IV’s continuous-shooting speed is rated at more than double the LX100’s, but in this class of camera the LX100’s 6.5fps may be sufficient for a lot of people. This is a comparison I can’t wait to see.