Introduction

Featuring a large 5.5-inch, high-resolution 1440 x 2560 pixel screen and running a powerful Snapdragon 808 chipset with quad-core 1.44Ghz and dual-core 1.82 Ghz Cortex processors, along with 3GB RAM, the G4 is certainly equipped for performance.

The primary camera is promising, too, offering a 16Mp (5312 x 2988 pixel) resolution on a 1/2.6in sensor, with the secondary camera still a respectable, albeit lower resolution, 8Mp snapper. Other notable camera features include laser autofocus, optical image stabilization, LED flash, simultaneous video and image recording, geo-tagging, face detection, and HDR processing. Shooting moving images, the G4 records at either 2160p/30fps or 1080p/60fps on the primary camera, and a lower-resolution 1080p/30fps on the secondary camera when Skyping and the like.

With so many DxOMark enthusiasts requesting an in-depth analysis of the G4’s image quality, we’re delighted to bring you a full round-up review of our latest mobile tests.

LG G4 photo sub-scores: A solid all-rounder

To evaluate the LG G4’s camera performance and image quality, our engineers tested the device under a range of different lighting scenarios.

In general, pictures are very well-exposed in both outdoor and low-light conditions, with pleasing colors, particularly when shooting in good light. Some exposure failures do occasionally occur, notably in scenes with high dynamic range, where the G4 tends to over-expose, resulting in blown-out highlights.

This over-exposure failure also affects the color of the sky, with some cyan tint in blue skies.

An odd white-balance error in outdoor shots was recorded, too, together with a slight pinkish cast apparent on low-light images shot under tungsten illumination.

Excellent detail preservation is apparent in pictures shot under all lighting conditions, however, with good noise reduction algorithms utilized to reduce chroma noise in low-light shots for smooth results. In large blocks of homogenous color, such as a clear blue sky, a build-up of luminance noise was noticeable in test shots, but it isn’t too offensive in print.

Artifacts are very well-controlled on the G4, too, with only slight color fringing noticeable in backlit scenes. Shooting directly into the low evening sun does result in some strong lens flare, but this is one of the most challenging conditions the small mobile phone lens will face. While some moiré is also visible on high-frequency patterns, and a slight ringing is noticeable in some outdoor shots, it’s only really apparent at 100% scale and to be fair, you have to look pretty closely to see it.

Using the G4’s built-in flash in low light results in good detail preservation and bold color rendering. The flash is centered, meaning that brightness drops off in the corners a build-up of chroma noise becomes visible. Flash colors are generally strong, and when mixing flash with a tungsten illuminant, white balance turns slightly greenish, but again, it’s not offensive.

For autofocus performance, the G4 is fast, accurate and consistent, particularly when shooting in good light, but the autofocus can lack smoothness and stability in preview.

Shooting in well-balanced and good outdoor lighting conditions, the LG G4 records excellent exposures with strong, vivid and pleasing colors.

In challenging light conditions, however, and in scenes with high dynamic range, images are over-exposed, resulting in blown-out highlights and an over-saturated blue sky.

In correctly-exposed outdoor shots, excellent detail is preserved in areas such as the building, but in homogenous blocks of color such as the blue sky, some luminance noise is visible.

100% crops captured under a low-light brightness of 20 Lux show how well details are preserved while at the same time keeping overall noise levels low.

Again, under the low-light 20 Lux illuminant and tungsten, light source exposures are accurate, but the white balance tends to turn slightly pink.

Shooting directly into the light, some lens failures are visible, including colored fringing along contrast lines and strong lens flare, but to be fair, these are challenging conditions for a small cameraphone lens.

Some other artifacts such as moiré on high-frequency patterns and ringing are sometimes visible on 100% crops, too, but you need to look pretty hard to see them.

LG G4 video sub-scores

Just like the stills, video from the G4 is generally very well exposed with strong and vibrant color. Shooting video in very strong light, the brightest highlights occasionally get blown out to bring more detail into the shadows.

With accurate video exposure, however, the G4 video displays good detail preservation and noise reduction. Under low light, the color rendering isn’t quite as strong as in good light, with some visible color shading and again, that slightly pinkish white balance when shooting under a tungsten illuminant.

The biggest video flaw is stabilization, however, with a noticeable jello effect along with visible juddering and residual motion apparent in some videos. As you can see from the diagram, however, this is an area many of the best mobile phone devices are having issues with and the G4 is actually slightly ahead of the iPhone 6 and Galaxy S6 Edge competition in this regard.

LG G4 vs competition: Podium position for image quality

Hitting the high notes for image quality in our rigorous industry standard tests, the LG G4 achieves an excellent overall result and slides into joint second place. With a DxOMark Mobile Score of 83 points, the LG G4 joins the Motorola X Style and Samsung Galaxy Note 4 in 2nd place, just a few points off from the current king of mobile image quality, the Samsung Galaxy S6 Edge with 86 points overall.

Drilling down into the Photo & Video sub-scores that feed into the overall DxOMark Mobile score, you can see that LG has made big strides forward for image quality on the G4 compared to the older G2 model. A big jump for stills image quality (up to 86 points from a previous of 77 for the G2) moves the G4 into 2nd place, ahead of Apple’s iPhone 6 with 83 points and just behind the S6 Edge with 88 points.

For video, the upward trend from the G2 continues, with the G4 taking a massive leap up to 79 points, compared to a previous score of just 64. The G4 ranks third for video behind the S6 Edge and iPhone 6, however, both of which have broken the 80-point barrier for video image quality.