Panasonic Lumix DMC-G7 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

Image quality from the Panasonic Lumix DMC-G7 is good. The native ISO 200 sensitivity is essentially noise-free, as are other sensitivities up to ISO 800 which barely shows speckles in luminance which have almost no impact on the finest details. This makes it easily possible to produce sharp 16" x 12" print and even slightly larger ones.

The Venus engine offers 11 levels of noise-reduction which affects the performance of higher sensitivities. Its default is somewhat aggressive with optimal output when it is set to -3. At that setting, visible noise increases steadily while maximizing detail retention. ISO 1600 and 3200 both produce impressive mid-sized prints, easily up to 12" x 9".

ISO 6400 is notably noisier which destroys fine details. Noise-reduction is gentle enough that it preserves a good amount of details and removes any chroma-noise. Mid-size prints may be acceptable for brighter subjects and small prints remain perfectly usable. ISO 12800 has even more noise and fewer details. It can make usable small prints but that is it.

The maximum ISO of 25600 is really noisy. One can still recognise a subject and make small images for web use. At the opposite end of the spectrum, the expanded Low ISO of 100 is noise-free yet distorts color and noticeably clips dynamic-range.

Sharpness on the G7 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 could be improved. Both Standard nor Natural photo-styles show shifts in color, with the red channel appearing more sensitive than it should be. Reality falls somewhere in between these two styles. Starting at Natural and reducing Saturation to -1 improves colors which then requires a +1 boost of Contrast for images not to look dull.

Automatic While-Balance performs somewhat below average. It balances colors well under natural light but often leaves a strong yellow cast under artificial lighting. This can be corrected using presets or Custom White-Balance which is quite accurate. One very welcome feature of the G7 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 and therefore allows white-balance fine-tuning to be used reliably. Be careful when changing sensitivity though because ISO 100 exaggerates the red channel even more.

Exposure

The multi-segment metering system of the Panasonic G7 is reasonable. It tends to produce bright images which forces highlights to be clipped more often than usual. For low-contrast scenes, there is no problem since this produces print-ready images right in the camera. Typical outdoor scenes though often show severely over-exposed areas due to the limited dynamic-range of the G7 which is unexpectedly below that of most mirrorless cameras. Again, ISO 100 compounds the problem by losing almost one stop of dynamic-range.

It is important to realize that the EVF and LCD are not Exposure-Priority, except optionally in Manual mode. They rarely preview exposure correctly, even for scenes that fall well within the metering range of the camera. There is an optional live-histogram which is not reliable either since it shows the luminance distribution of the display rather than the expected exposure. While there are 4 options for Monitor Luminance, none is reliable.

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 G7 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 G7 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 G7 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: Under 1s. Very good.
• Power-On to First-Shot: 1¼ seconds. Quite good.
• Autofocus: Under ½s normally, up to ¾s in low-light. Good.
• Shutter-lag: Instant with about ¼s blackout. Excellent.
• Shot-to-shot: ¾s with AF, just over 1/3s without. Superb.
• Playback: Instant to enter, ½s to exit. Good.
• Power-Off: 4s. Glacial.
• Video: Instant to start or stop, pause 1½s after to flush buffer. Very good.

This G7 delivers impressive numbers in nearly all areas, almost identical to the speed of the flagship GX8. Autofocus was measured to be slower which is most likely due to the Panasonic Lumix G Vario 14-42mm F/3.5-5.6 Mega OIS II
Panasonic Lumix G Vario 14-42mm F/3.5-5.6 Mega OIS II lens compared to the Panasonic Lumix G X Vario 12-35mm F/2.8 ASPH OIS
Panasonic Lumix G X Vario 12-35mm F/2.8 ASPH OIS used for the Panasonic GX8 review
Panasonic Lumix DMC-GX8. These cameras otherwise appear to use the same autofocus system with innovative Depth-From-Defocus (DFD) technology.

The lower resolution sensor uses less power than the 20 MP counter-part in the GX8. This gives the G7 a better battery-life of 350 shots-per-charge which is still below average for a mirrorless. Plan to keep at last an extra battery for a full day of shooting. The only inexplicably slow number is the time it takes to power off. The camera takes a short pause after filming which is not ideal but, at least, it starts filming immediately.

The Panasonic Lumix DMC-G7 is a prosumer mirrorless that offers a rich feature-set in a relatively light-weight body without compromising on ergonomics. Its dual control-dials, numerous buttons with many customization options and a large 0.5" protruding 2.4 megapixels EVF with Eye-Start sensor make it efficient and a pleasure to use. It sits just below the flagship GX8
Panasonic Lumix DMC-GX8 in the Panasonic mirrorless lineup only due to its lack of image-stabilization and weather-sealing.

Image quality is quite good. Image noise is well under control and details stay remarkably intact as ISO increases. Maximum size prints look great until ISO 800 while mid-sized ones are easy possible until ISO 3200. The new processing engine is faster than previous generations yet lags in terms of output quality. While sharpness and noise-reduction are very good with the right settings, colors and white-balance have room for improvement. This, of course, is entirely avoidable by those who shoot RAW.

The real issue with the G7 is that its metering tends towards over-exposure which happens quite often considering the sensor in this digital camera does not have as wide a dynamic-range as other recent mirrorless offerings. One could judiciously apply Exposure-Compensation to correct metering if only the EVF and LCD were Exposure-Priority which is only possible for Manual exposure.

The Panasonic G7 is impressively fast. With exception to slowness while powering-off, which is rather unimportant, the G7 is consistently fast. Shot-to-shot speed and black-out time are very impressive. The AF system is extremely sensitive, highly accurate and speedy.

Along with a complete set of advanced photography features, the G7 offers top-notch video capabilities. It is one of the lightest mirrorless to capture 4K Ultra-HD video which it does with a slightly reduced field-of-view to avoid under-sampling artifacts. It can also capture 1080p HD video at 60 FPS with full coverage. Video quality is excellent and the camera starts recording immediately from its dedicated Video mode.

The final word on the Panasonic G7 is that it is a highly capable camera with only one major flaw which is its multi-segment metering system. Still, this mirrorless is capable of producing some fantastic images with good sharpness, superb retention of details and low noise, all from within an efficient and ergonomically-designed camera body.