Panasonic Lumix DMC-GX8 Review

Performance starts with image quality, which is the criteria used as the foundation of our digital camera ratings. Ergonomic issues may get in the way, but in the end, image quality counts the most. For an ILC, image quality greatly depends on the lens used. While color, noise, exposure and dynamic-range are properties of a camera, distortion, vignetting and chromatic aberrations are properties of the lens. Sharpness and contrast depend on the weakest link. That is, a camera cannot capture more details than a lens lets through. Conversely, it is quite possible for a lens to transmit more details than a sensor can capture.

Image Noise & Details

The Panasonic Lumix DMC-GX8 outputs high quality images. The 20 megapixels Four-Thirds CMOS sensor is paired with a speedy Venus Engine which offers 11 levels of noise-reduction. Dialing down from the default to -3 produces the optimal balance between details and noise. This allows the maximum GX8 resolution to be used up to ISO 800 where noise is barely noticeable. This makes for very sharp 20" x 15" prints.

ISO 1600 is almost as clean with a tiny amount of luminance noise. This noise has a fine-grain pattern and leaves fine details almost completely intact. Potential prints sizes get slightly affected, losing about one usable inch linearly. By ISO 3200, there is a light but obvious noise and the finest details begin softening. One can still manage impressive and moderately large 16" x 12" prints.

There is obviously an increase of noise and decrease in sharpness at ISO 6400. The noise reduction processing still manages to produce smooth surfaces and leave details in relatively good shape. At this ISO, one can pull off medium-sized prints. ISO 12800 is very noisy with small details gone. Given 20 megapixels though, clean small prints are still possible.

The maximum ISO of 25600 is remains usable for emergencies only. Noise is clearly visible with patch grain obstructing details. What is nice is that the GX8 manages to keep contrast consistent until ISO 6400 while colors remain steady all the way to ISO 25600.

Sharpness on the GX8 is adjustable in 11 steps, like most other image-parameters. The default is slightly soft. Raising it to +2 improves things considerably while introducing only minor sharpening artifacts. Higher levels show clear halos which makes images look like paper cut-outs.

Color & White Balance

Color accuracy is reasonable. Neither Standard nor Natural photo-styles are great, reality falling somewhere in between these styles. Starting at Natural and reducing Saturation to -1 gives the most realistic colors which then requires a +1 boost of Contrast for images not to look dull.

Automatic While-Balance performance is better than average. It compensates well for a good variety of lighting, producing results with a minimal cast under most conditions. To perfectly control color-balance, Custom White-Balance is spot on. One very welcome feature of the GX8 is that the LCD can be adjusted in terms of Saturation and Tint along 2 axis. This makes it possible to calibrate the display so that it correctly previews white-balance. This makes it possible to fine-tune white-balance reliably.

Exposure

The Panasonic GX8 has an excellent multi-segment metering system. It is generally conservative and with only occasional over-exposure in the presence of small highlights. For low-contrast scenes, it needs a little positive compensation but less than most cameras.

The dynamic range of the GX8 is good considering it has smaller pixels than previous Micro Four-Thirds digital cameras. The new 2.4 megapixels 0.44" OLED panel which makes up the EVF has an incredible 10000:1 contrast-ratio which makes it possible to see the full contrast of most scenes. The 1 megapixel 3" rear display also features an OLED panel, although it loses contrast due to ambient lighting.

It is important to know that the EVF and LCD are not Exposure-Priority. They only preview exposure for scenes which fall well within the metering range of the camera and only in an automatic or semi-automatic mode. The optional live-histogram is not reliable either since it represents the luminance distribution of the display rather than the expected exposure. Optionally, in Manual mode, the EVF and LCD can simulate exposure.

Auto Focus

This mirrorless digital camera has a very fast Contrast-Detect autofocus system. It locks focus quickly. Even in moderate light, it locks focus in ¼s. Under low illumination, it can take a little longer but rarely more than ½s. This new Contrast-Detect AF offers a class-leading sensitivity, down to -4 EV which exceeds the capability of nearly every other camera.

To speed things up, Panasonic provides two options: Quick-AF and Eye-Start AF. For the former, the GX8 starts focusing as soon as the camera is held steadily, presumably because the photographer is getting ready to take a shot. The the latter, it starts when the Eye-Start Sensor gets triggered. When the shutter-release is pressed halfway, the GX8 then only needs to adjust focus a little but this can also makes things jumpy when doing multiple shots that need to match for things like HDR or panoramas.

Speed

The Panasonic GX8 is extremely responsive. This camera does not slow the photographer down, every button press and dial turn is immediately registered. Its performance is characterized by the following numbers:

• Power-On: Just under 1s. Good.
• Power-On to First-Shot: 1¼ seconds. Quite good.
• Autofocus: ¼-½s even in low-light. Excellent.
• Shutter-lag: Instant with about ¼s blackout. Excellent.
• Shot-to-shot: ¾s with AF, 1/3s without. Superb.
• Playback: Instant to enter, ½s to exit. Good.
• Power-Off: 1½s. Average.
• Video: Instant to start or stop. Perfect.

This GX8 delivers impressive numbers in nearly all areas, exceeding even the GX7 for some measurements. Most importantly, it no longer clips the ends of video. The only number which actually lowered is battery-life. It is now rated at 310 shots-per-charge and this is without flash since the GX8 does not have one. Keep at least 2 extra batteries for full days of photography.

The Panasonic Lumix DMC-GX8 lifts the GX-series to fully-professional level with a new sturdier weather-sealed body. Uniquely, its built-in sensor-shift stabilization now cooperates with lens optical stabilization to realize lower shutter-speeds and sensitivities than otherwise possible. This mirrorless also introduces a 20 megapixels CMOS sensor, the highest Micro Four-Thirds resolution.

Image quality is impressive considering the higher resolution. Results are completely usable up to ISO 1600 and even higher for mid-size prints. Metering is excellent while colors and white-balance are not perfect yet reasonable. They can be easily adjusted to taste in fine steps.

The Panasonic GX8 is even faster than its predecessor in several areas. This makes it still one of the fastest mirrorless cameras in the market. The new Contrast-Detect AF system is very quick and extremely sensitive while the large 0.77X magnification 2.4 megapixels 0.44" tilting EVF remains remarkably usable in low-light.

The feature set of the GX8 is truly outstanding. It puts the user in direct control of the camera and offers useful photographic tools such as 7-frame AEB, fine control over autofocus, WB fine-tuning and plenty more. Video recording up to 4K Ultra-HD is now possible which this mirrorless does with ease. Plus, as a member of the Micro Four-Thirds family, the GX8 has access to the most extensive lens lineup made for mirrorless cameras.

Panasonic reached an even higher step with the Lumix DMC-GX8 with its combination of image-quality, performance and capabilities. The higher cost and heavier body are a reasonable price to pay for such improvements, particularly considering the added weather-sealing.