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The Sony Cyber-shot RX100 IV (M4) is less of an clear upgraade over its predecessor the RX100 III (M3) than a forked alternative; for a variety of reasons, I'd classify it as an advanced compact for video enthusiasts rather than a straight-up advanced compact, at least until the price drops a bit. Though it's more expensive and adds a plethora of video capabilities, it's pretty much delivers the same photo quality in the same body.
Officially priced at $950 (£920, AU$1,400), the M4 goes up against the less expensive Panasonic LX100 ($800, £700, AU$1,000), which also shoots 4K, though doesn't offer quite the breadth of video-related features that the M4 does.
Despite using a completely new -- but same size and resolution -- sensor, the images from the M4 look quite similar to those from the M3. The new stacked CMOS sensor, branded Exmor RS, gives the photosites their own layer while the circuits occupy the layer beneath. But the modification doesn't seem to have had a big impact on photo quality. It displays slightly better noise performance above ISO 800, with more detail preserved in dark areas, but nothing jumps out as "wow" better.
The photo quality is still quite good, sharp with decent color and tonal range, though I don't think surpasses the lower-resolution but larger-sensor LX100. There isn't a lot of detail to recover in the highlights.
The video quality is very good, as sharp as you'd expect from 4K. While I prefer the more accurate rendering the LX100 produces with little fiddling, the RX100 IV has tons of controls to get the results you want along with a quieter lens and adjustment dial.
The new sensor uses 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. There's still quite a bit of wobble that comes from camera shake when the image stabilizer is in Standard mode -- that's the best you can get when shooting 4K.
The RX100 M4 really does improve over the M3 in most -- though not all -- aspects of performance, and ranks as one of the fastest compacts we've seen. Like other cameras with zoom lenses, and unchanged from the M3, it's relatively slow to startup since you've got to wait for the lens to extend. Once extended, though, it's consistently fast: about 0.2-0.3 second to focus and shoot, regardless of lighting conditions, and 0.2 second for two sequential shots, in both raw and JPEG. With flash enabled that time increases to about 2.3 seconds, also unchanged from the M3.
The biggest deal for the M4 is its much hyped continuous-shooting performance. On one hand, its tested rate of 5.7 frames per second for JPEGs and 5fps for raw, both for at least 30 shots and with autofocus, is very good for this class.
But the camera's actual high-speed shooting is far more complex than a spec conveys. With the mechanical shutter enabled and with autofocus, it drops to 2.4fps; the faster rates require the electronic shutter. (One of the differences between the M4 and its predecessors is the ability to manually select mechanical or electronic shutter, though there's still an auto option.)
In the limited number of situations where you can forgo autofocus and autoexposure, usually when people are standing in one place and moving just parts of their bodies, Sony's Speed Priority Continuous can do 10fps with the mechanical shutter and 16fps with electronic. There's quite a wait for the camera to process the photos before you can get into playback or the menus, though it doesn't stop you from continuing to shoot.
The autofocus works pretty well, although when you use continuous AF and see the way it pulses for every exposure you can tell why it the burst with AF is so much slower. I didn't have much luck with the object-tracking autofocus either, as (like most) it's easily distracted by objects which cross your subject's path. The single-shot autofocus is pretty good, but the Wide-Area AF -- Sony's version of leaving the choice of AF subject to the camera -- performs about as well as other cameras'. That is, when zoomed out it selects everything in the scene and when zoomed in it selects the closest objects.
Sony's high frame-rate mode lets you record at 240/250fps, 480/500fps or 960/1000fps (NTSC/PAL) in a variety of standard rates ranging from 24p to 60p, which it saves as a 1/4 speed to 1/40th speed playback in a variety of sizes and qualities. You can choose any of the semi-manual PASM modes, To use it, you select HFR on the mode dial, select your settings and focus (either manually or with continuous AF), then press the standby button. When your moment comes, you hit record. It takes a while to process the video, so there's a cancel option.
It's both a fun and frustrating feature, and seems ill-suited to spur of the moment recording. Though Sony gives you two capture choices -- trigger to start recording and trigger to end recording -- it's frequently aggravating to use. First, it can only capture 2 seconds worth of best-quality or 4 seconds of meh-quality video (that is, say, 2 seconds of 240fps capture results in 8 seconds of video), and that doesn't give you much wiggle room to time the triggers right so that you get the frames you want, so I suggest you practice a lot before trying it on something that matters.
Second, it can't focus when it's in standby mode, so you have to go out, focus, then go back in. When you're in continuous AF mode, that means you have to get out, position the camera, wait for it to focus, then hit standby again. If your subject moves, reposition, rinse, repeat. Oops, moment missed. Since the whole procedure really requires some deliberation, you're really better off manually focusing, anyway.
And finally, the battery life is terrible -- even worse than the M3's. Sigh.
With the exception of changes to the mode dial, the design of the M4 is identical to the M3, both the good and the bad. It's still one of the most pocketable cameras of its type, with an ingenious pop-up viewfinder. (Which now has an option to leave the camera on when you push it in.)
The top mode dial finally merges the three auto modes into a single Auto to make room for the aforementioned HFR option. The rest are the same manual, semimanual and automatic modes,, a dedicated movie mode (with a full set of manual and semimanual exposure controls) and Sweep Panorama. You can tilt the popup flash for better control over intensity and direction to bounce the light or simply prevent hot spots.
As with its predecessor, I like the control ring, which you can program to operate for one default setting (such as stepped zoom or shutter speed) and to use in conjunction with a Custom (C) button, which you can program to access more settings. The camera can be customized quite a bit. In addition to the Fn button, you can also reprogram the operation of the left and right navigation keys on the back dial as well as the center button. And there's a Memory Recall option on the mode dial so you can select from three custom settings slots.
The LCD remains visible in direct sunlight, and the electronic viewfinder, while quite small, does the job.
The gripless body is still slippery; I dislike the small, flat movie button; and it lacks a hot shoe. That last is somewhat acceptable in a camera half the price, but the M4 is almost $1,000. And it retains some implementation issues from its predecessors including Auto flash only available in full auto mode, and you still can't manually invoke macro mode.
In addition to the features of the M3 and capabilities mentioned earlier, the M4 adds movie-friendly features like framing markers (Center, aspect ratio, safety zone and guides), control over zoom speed (normal or fast), timecode and user-bit (essentially hexadecimal timecode) control and display and simultaneous recording to card and clean HDMI out. Although I didn't mention it for the M3, the M4 also includes support for Picture Profiles, which allows you to control tonal-range rendering in movies. (Picture Profile details.) And unlike previous models, the M4 also supports tethered shooting via Sony's Remote Camera Control software. It also ships with free access to a Sony-specific version of the excellent Phase One Capture One Express 8 for raw processing in a nice break from the usual lame bundled software.
The one seriously annoying aspect of the video operation is the XAVC file structure on the card which carries over from the hideously annoying AVCHD structure. Not only do you have to plow through multiple folder levels simply to find your videos, but there's no way to force it to use serial file names; every time you format the card, it restarts the naming scheme at the beginning, which means when you copy the files to the same directory as files from a previous shoot, you have to rename them or overwrite the older ones.
It uses the same Wi-Fi implementation as recent Sony models, including support for Sony's proprietary PlayMemories app ecosystem. You have to download the free Smart Remote app if you want anything more than basic remote shutter capability, a fact which gets more irritating with every camera I test. Entering Wi-Fi passwords via the non-touchscreen keyboard to download apps is no fun. But you can connect the camera directly to your system to download them, although I could only get it to work with Internet Explorer.
I had no trouble with the NFC/Wi-Fi connection to my phone, though without any downloaded apps its capabilities are pretty limited to transferring files and firing a remote shutter. Key features like time-lapse, multiple exposure and distortion correction are only available as extra-cost apps, ranging from $5 to $10.
In order to record the XAVC S video (both HD and 4K) you need a 64GB SDXC Class 10+ UHS 1 card; UHS U3 for bitrates higher than 100 megabits per second. While the manual finally makes that explicit, the messages on the camera don't -- it simply says "switch to a UHS-1 U3 compatible card". So in a testing pinch I ran out and got a 32GB card and couldn't figure out why it wasn't working until I got back to the office and checked the documentation.
Sony has cleaned up the interface for selecting effects, though there aren't any new ones or additional options, and they're still not accessible in raw or raw+JPEG mode (though the camera doesn't bother to tell you that's why they're grayed out) so you can't save a simultaneous version without effects, and you can't control any of the parameters.
For a complete accounting of its features and operation, download the RX100 IV's manual. Choose "Help Guide (Printable PDF)", not the confusingly named "Instruction Manual."
If you're simply looking for an advanced compact for still photography, cheaper models like the RX100 III or the LX100 are better bets; they deliver equal or better photo quality, and while the LX100 is a little slower, it's still in the same ballpark. But if you want the smallest camera with the biggest video capabilities, the RX100 IV is the one.
|Panasonic Lumix DMC-LX100||Sony Cyber-shot DSC-RX100 III||Sony Cyber-shot DSC-RX100 IV|
|Sensor effective resolution||12.8MP MOS||20.2MP Exmor R CMOS||20.2MP Exmor RS CMOS|
|Sensor size||Four Thirds |
|Sensitivity range||ISO 100 (exp)/ISO 200 - ISO 25600||ISO 80 (exp)/ISO 125 - ISO 12800||ISO 80 (exp)/ISO 125 - ISO 12800|
|Lens (35mm equivalent)||24-75mm |
|Closest focus||2 in/3 cm||1.9 in/5 cm||1.9 in/5 cm|
|Burst shooting||6.5fps |
(40fps with electronic shutter and fixed AF/AE)
(10fps with fixed focus and exposure)
(with electronic shutter; 16fps with fixed focus and exposure)
(mag/ effective mag)
0.4 in/10.2 mm
|OLED EVF |
|Shutter speed||60 - 1/4,000 sec (1/16,000 electronic shutter); bulb to 2 minutes||30 - 1/2,000 sec; bulb||30 - 1/2,000 sec (1/32,000 electronic shutter); bulb|
|Best video||MP4 UHD/30p, 25p, 24p @ 100Mbps; 1080/60p, 50p||XAVC S |
1080/60p, 30p, 25p, 24p @ 60Mbps; 720/120p
|XAVC S 4K 2160/30p, 25p, 24p @ 100Mbps|
|Manual aperture and shutter in video||Yes||Yes||Yes|
|Maximum best-quality recording time||15 minutes||29 minutes||5 minutes|
|Optical zoom while recording||Yes||Yes||Yes|
|LCD||3 in/7.5 cm |
|3 in/7.5cm |
(plus another set of white dots for brightness)
(plus another set of white dots for brightness)
|Wireless connection||Wi-Fi, NFC||Wi-Fi, NFC||Wi-Fi, NFC|
|Battery life (CIPA rating)||300 shots||320 shots (LCD); |
230 shots (Viewfinder)
|280 shots (LCD); |
230 shots (Viewfinder)
|Size (WHD)||4.5x2.6x2.2 in |
|4.0x2.3x1.6 inches |
|Body operating weight||13.9 oz |
|10.2 oz |
|Mfr. price||$800 |
|Release date (US)||November 2014||June 2014||July 2015|