So the rumors proved to be accurate on the GH5s and now we have a low light version of the GH5 that can shoot cleanly up to ISO 12,800 with up to 100k ISO and by then a much noisier picture. It is claimed by Panasonic that there was a 1.5 stop improvement in noise performance.  Judging by the initial video samples it is clear that the new 10.28MP sensor along with dual native ISO circuitry for each photosite “one at ISO 400” and “one at ISO 2400” make a huge performance leap if low light is desired in a m43 camera.

All is not rosy in Lumix land however as the camera now lacks IBIS or In Built Image Stabilization on the sensor which was a main selling point of both the GH5 and the G9.  Panasonic claims that it was a decision made to cater to filmmakers that need no wobble or vibrations in a shot that can be produced when the stabilizer fails. But why not just add an On-Off switch? 1080p 240fps is also included in the camera but as initial samples show it reduces quality substantially.

Panasonic Lumix GH5S Main Specs:

• 10.28MP Multi-Aspect Ratio MOS Sensor
• DCI Cinema 4K – 50-60p 
• Full HD 1080p 240fps Slight Crop!
• Internal 4:2:2 10-Bit Long GOP
• V-Log L Gamma and HDR Hybrid Log Gamma
• 0.76x 3.68m-Dot OLED Viewfinder
• 3.2″ 1.62m-Dot Free-Angle Touchscreen
• Dual Native ISO 400 and ISO 2500
• Dual UHS-II SD Slots; Wi-Fi & Bluetooth
• Advanced DFD AF System
• 12 fps Cont. Shooting and 4K PHOTO Modes
• MSRP $2,499.99 USD -Pre Order Here!
• Release Date End of January-Start February 2018!

Panasonic GH5S Video Hands-On – Highlights of the New Camera by cinema5D:

GH5s VFR Slow Motion performance?

As you can see from the excellent first look video above by Cinema 5D the video quality in low light is very much improved from the GH5 and G9. However, the slow motion at 240fps is full of resolution loss, jaggies, and moire which is to be expected as information is being thrown out to cope with the data rate.  This begs the question so what does it look like up to 190fps which is the limit before the VFR mode starts to crop the image. We estimate that it may actually do better than the GH5 and G9 at 190fps and below in which those two other cameras suffer resolution loss as well.  It will be interesting to see if the 180-190fps GH5s is excellent quality. There might be something to cheer here for high frame rate enthusiasts.

Panasonic LUMIX GH5S – Variable Frame Rate (VFR) for Impressive Slow Motion by PanasonicLumixVideo:

However, if you wanted 1080p at 240fps with the quality of an FS700 or similar you will not get it here. The video by Lumix Panasonic above shows a softness and aliased video at the higher frame rates while 120fps seems more subdued.

We were not thrilled about the Panasonic EVA-1 240fps mode in full HD which also had resolution loss and higher noise compared to the full sensor mode, it seems the GH5s is suffering from the same affectation above the 180fps threshold.  We will have more from this feature as tests start to flood the web.

No IBIS-No Deal – Does the “s” Stand for “Shake”?

Much like the addiction suffered by FED’s Quantitative Easing in the financial markets since the great recession, the IBIS stabilizer feature introduced in recent Lumix cameras has had a big effect in the way people shoot with the camera hand-held and depend on the feature to shoot stills in lower light levels without a tripod.  Now the GH5s has been announced with no stabilizer inside but only to rely on the Lumix lenses for shake reduction.

Kai Introducing Panasonic GH5S by CVPTV:

For many, this will be a deal breaker right off the bat. Cameras in the Sony stable feature impressive low light performance without sacrificing IBIS and offering even better low light by many measures to the GH5s.  It is as if you get a beefier HP engine but you will have to forgo the shock absorbers in a brand new car.  So you will develop a back problem while speeding down the road.

Panasonic GH5S Takes On Sony a7S II? Another Not-So-Secret Convo with Panasonic’s Sean Robinson by Three Blind Men and An Elephant Productions:

In the video above Sean Robinson the Panasonic representative elaborates on the reasons why the GH5s has no IBIS inside the camera. It seems film makers have issues with IBIS as it can induce wobble and vibrations that could overcome the delicate magnetic properties of the system and ruin a shot when using the camera in rugged environments. Also that frees up processing power to improve the camera’s bit depth in stills to 14 bit and do better image processing in video mode while improving AF using the depth contrast method.

Even if the wobble image problem is true, we have not seen any footage being destroyed the GH5s IBIS and many movies use GoPro footage which is full of rolling shutter.  We believe the main reason for the IBIS let down is the new multi-aspect sensor which is larger than the one in the GH5 which makes it harder to incorporate effective stabilization.

It seems the GH5s is cramped for space in the sensor block and along with the new circuitry for the dual Native ISO MOS sensor makes it impossible or very hard to incorporate a good IBIS system.  If this is the came then that would explain the decision. But if it is not then why not add it and offer the same menu function as in the other cameras to turn it off? On-Off seems like a reasonable way to deal with wobble artifacts if needed. It may be that even while off the floating sensor module could vibrate in the holding with a bumpy ride, hence the need for a fixed hard placement. We will probably never know for sure.

Early Stages More Testing Needed:

The GH5s is a good camera overall for video shooting and a great camera for low light shooting compared to what came before it in the m43 space.  However, if you already own a GH5 or G9 we really cannot find reason enough to replace them for the GH5s.  It seems this new camera is aimed at a specific niche market and to appease the low light negativity threads that seem to always plague any m43 camera release. The company will point out to the GH5s as their answer.  However, we are more inclined to still recommend a GH5 above the GH5s for slow motion based on cost alone and the inclusion of the IBIS stabilizer.

Hands-On Review Panasonic Lumix GH5S by B&H  High ISO TEST!

The GH5 is a workhorse camera that is able to shoot excellent quality video.  The recently released G9 is also a fantastic option but with a quality drop in the slow motion codec bitrate that could cripple it in a head to head match.

The 240fps mode in the GH5s makes us giddy with excitement but at what cost?  The quality drop is enough to render it useless in a broadcast environment and with severe artifacts.  More samples are to be analyzed before we can add it to our camera guide, however.

The big competitor to the GH5s will be the Sony a7s III which is expected this year. With their revolutionary Auto Focus performance and also the big possibility of IBIS in the full frame sensor.   The Low light of the a7s Mark I and II already destroy the GH5s so a new a7s Mark III will make the competition harder.  The m43 cameras are constrained by the sensor size and current technology relies on larger photo-sites to deliver the goods when it comes to sensitivity, there is no question a larger sensor will have the advantage.

The only real question at the end of the day, is how much are you willing to pay for that added edge in performance?  -HSC