Review of a very 4K-apable camera – the RX100 IV

When Sony introduced back in 2012 the first model from the what will become the RX100 series (I’ve wandered in Dobrogea with the first model and the review is here), the compact camera market was taken by surprise and well shaken by the success the first RX100 model saw among both enthusiast and professional photographers alike. As a proof to that the camera still sells.

The evolution of RX100 series

RX100 IV and all other RX100 models

There were many similarities from one model to another, especially on the outside, but the Japanese camera maker added many upgrades from one model to the next in the series. Here is a short reminder of the features added after the first model was released.

RX100 II (the review I did is here) came with a new BSI Exmor R CMOS sensor, tilting LCD (compared to fixed one on first model), native ISO range from 160-12.800 (compared to 125-6.400 of the first RX100 model), NFC and a Hot Shoe where you could mount an EVF, microphone or a big flash.

The third iteration, the RX100 III, came with the same retroilluminated sensor but with the new (and current) better processor Bionz X. The lens focal range was changed to a shorter but more brighter aperture 24-70mm f/1.8-2.8 Vario-Sonnar T*, compared to the previous longer but less wide 28-100mm f/1.8-4.9 (equivalent in 35mm focal lenghts) on the first two models.

The back LCD was still a tilt one but now with a selfie function (180 degrees tilt up angle). The most important added feature was the new pop-up EVF at the cost of the hotshoe. ISO native range was extended to 125-12.800 and for the first time XAVC S coded appeared on the series (though I don’t remember exactly if it came with the initial firmware or as an upgrade like the a6000 received). 5 axis stabilisation was added (compared to 3 on the previous models) and Intelligent Active Mode steady shot was added for video.

So here we are to the 2015 model (launched back in June in London where I got the chance to do a hands on), the 4th iteration of a great series. I would have called this camera directly RX100 4K. Why so?! Let’s see…

Test with the new Sony RX100 IV

Although outside differences are mostly inexistent between the two last models, we can find inside the most notable differences. The “goodies” are inside.

RX100 IV vs RX100 III

3 visible diferences on the outside: 1. zoom ring texture 2. text identifying the model and the sensor type RX100 IV Exmor RS 4K 3. mode selector – for the first time Sony move the two stupid almost identical auto modes icons into a single one Auto and leaves room for the new HFR mode. That’s all!

The newly stacked Exmor RS CMOS of the RX100 IV is solely responsible for the most inside improvements of the new model. It’s incredibly fast in processing data due to the stacked DRAM chips, integrated into the sensor which enable crazy fast readouts. The result is processing images 5x faster than the previous model and this translates into:

  • an incredible burst of 16 fps with focus and exposure locked on the first picture taken

  • 5.5 fps with continuous focus and EYE-AF tracking

  • 4K internal video with 100 Mbps bitrate (some slow-motion included in the 4k video below)

  • super slow-motion (HFR – high frame rate) up to 1000 fps (500fps and 250fps also available)

A thing to mention. When shotting in HFR (High Frame-Rate) the capture of the clip is somehow different with Sony RX100 IV compared to the normal video recording. First you won’t start it directly with the REC button (which by the way can be finally mapped to any other configurable button on the camera).

We have to chose in the menu what we want REC button to do: to start the recording or to stop it (2s in Quality Priority mode or 4s in Shoot Time Priority mode).

Somehow confusing, right? Not really, after you get to understand how things works. Camera enters a buffering mode when you press the Center Button (that means it records as long as it can in the incredible fast DRAM memory directly on sensor). During this time, you won’t be able to operate any other controls on the camera – like zoom, focus (even manual focus) etc. We just decide when to press the REC button. When you do so, the RX100 IV dumps its recordings from the DRAM to the card, upscaling the video to 1080 either in 25p or 50p (this will give slower and respectively faster playback of the final clip).

I’ve found more usable the post-action recording, that means I’ve set the REC button to stop the recording. This way I could see on the LCD the action taking place, and then I’ve quickly pressed the REC button to save it to the card. It’s hard to tell when a bee will fly from the flower, but if you see it, then you just tell the camera to stop the buffering and save the last seconds recorded to the card. Again an HFR random things video, just to show you how much I’ve enjoyed this mode :).

You have to play with both recording types to see which one suits you best.

  • 100 fps full HD – this again allows some beautiful slow motion (up to 4x when playback is edited in post-process at 25p). The advantage is a normal video recording. Also, the superb Picture Profiles of the A7s are included in the new RX100 IV, so you can play at the pro level with list little gem. Below some 100p, s-Log2, Cine 2 or Movie curves examples. It’s a nice added bonus the internal ND filter which eats 3 EV stops, so you can play with s-Log 2 outside with faster aperture (it raises the ISO to the minimum 1600 for the best dynamic range

Take into account an annoying bug when using the ND filter when recording video. You can set it to ON, OFF or Auto while shooting photos, but in video, Auto is disabled and the camera defaults to ON. When you come back to shooting stills, it won’t revert back to Auto and you might find yourself losing 3 stops of light due to this.

Even so, I love the internal ND filter because it allows long exposures like the one below during daytime

RX100 IV ND filter demo

ND On | F11 | 1/8s | ISO 80

  • 1/32.000 s minimum shutter speed. It’s rare when you need such an extreme speed to capture a scene. Even shooting the sun directly in the frame I barely hit 1/20.000s wide open

Minimum shutter on RX100 IV

  • shooting 17Mpx stills during video recording but only if you shoot in Full HD 25p
  • Dual recording – it allows recording of smaller Mp4 version videos of the 4K or full HD in XAVC S codec, for easier sharing or file management.

The new EVF of the RX100 IV is still “T* coated” but much sharper due to increased resolution (2,359k compared to 1,440k on the RX100 III). Another added benefit many will love is the Auto ISO minimum SS – that lets you choose the minimum threshold before the camera raises the Auto ISO with another step.

Image quality on RX100 IV

As expected, the camera produce superb images like its predecessor. But with a new and improved focusing system, a better dynamic range of the new sensor and the superb Vario-Sonnar T* lens, this little RX100 IV keeps without any doubts its first place as the best premium compact out there in the wild.

I let you enjoy a gallery of images shot with the RX100 IV

I wanted initially to do a versus between the last two models of the RX100 series but I concluded I won’t make any justice to either camera. Both are extremely incredible little gems, with an outstanding image quality for an 1″ sensor.

Instead, I’ve focused my review more on the goodies that comes with the new RX100 IV. In its favour, the RX100 III has the much lower price. But if you think you need the new video features the RX100 IV comes with, then you’ll know what to chose. At least I hope my review will help you decide on this matter.

Only good things about it?

Of course there is no perfect camera or at least one to make everyone happy. This is what bothered me about the new model:

  • battery goes faster than melting ice on a hot summer day when you shoot in 4K or in HFR mode. Along with this comes a very hot camera body
  • ND filter which stays ON when coming from video modes back to stills
  • the so many new features added to already a clumsy menu system, makes creating the best shortcuts to access features a haunting task. The small number of configurable buttons on RX100 series forces you very often to visit the menu to change things
  • EVF gets very dirty with fingerprints quickly due to the method needed to put it back to its place, because you push it with your thumb (so was the case with the RX100 III)

But I really did appreciate:

  • superb dynamic range of the new Exmor RS sensor
  • focusing speed and perfect exposure with every frame shot
  • cherry on the cake with this new model is undoubtedly the HFR mode (you could tell from the so many examples I took that I really loved this feature)
  • impressive quality of the 4K videos and of the HD ones when using the XAVC S codec
  • Picture Profiles as in A7s
  • sharpness of the new EVF
  • new Expanded Flexible Spot focusing mode
  • the fact that finally we can remap the video REC button to any customisable button on the camera
  • noul si imbunatatitul Auto ISO minimim shutter speed
  • electronic shutter which allows stupid fast shutter times (1/32.000 s) and also Silent Shooting so the subject won’t hear you at all when being photographed
  • Intelligent Active Steady Shot on video that gives steady-cam like results

Did you enjoy it? Please let me know in the comments if there are any other unanswered question you might have after reading my review.

Author: Alin Popescu

Inginer ca formare, grafician ca meserie, fotograf ca mod de viata, Alin este pasionat de tot ce inseamna tehnologie si scrie articole detaliate pe intelesul tuturor.

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