Image Quality and Performance

The Galaxy S6 Edge comes with Samsung's latest and greatest octa-core in-house processor, so it's not a surprise that it feels very responsive and quick in general use. The camera app opens up very quickly as well, which is great for capturing those unexpected moments. It only takes approximately 0.5 seconds to open via a double-click of the home button or the icon on the home screen;  it takes just a fraction longer when opening it from the lock screen. 

Autofocus works swiftly as well. In bright light it locks on very quickly at just over 0.5 sec. It can slow down considerably in very low light but generally stays reliable until things get too dark to find a lock. Of course it all depends on how much of a power user you are, but generally battery life is not a concern on the Galaxy S6 Edge. On our photo excursions we never even got close to running out of juice and even if you do get stranded with a flat battery the quick charging mode means you'll be back out on your way after only a brief pit stop.

Daylight, Low ISO

In good light the Samsung Galaxy S6 Edge produces excellent image quality. Exposure and white balance tend to be spot on and the images show good detail. At a 100% view there are some signs of noise reduction but well within acceptable limits, and thankfully Samsung has not pushed the sharpening up too high. The lens of our test unit is sharp across the frame and we did not notice any lens flare in our samples, even when shooting in very bright conditions. Images are also virtually free of chromatic aberrations or other artifacts. Noise, although visible in areas of plain color, is almost negligible. 

As usual colors are a little on the saturated side of things but images still retain a fairly natural look. Like on all cell phone cameras with small sensors, limited dynamic range can lead to highlight clipping in high-contrast scenes but the S6 Edge performs pretty well in this respect and activating the efficient and fast HDR mode can help a lot in both bright and low light. 

Overall the Galaxy S6 Edge delivers issue-free bright-light images that are among the very best we have seen from conventional smartphones with small image sensors. In Pro Mode you can fine-tune exposure and white balance but in almost all situations trusting the auto mode will get you decent results.

ISO 40, 1/1472 sec
Good detail across the frame
100% crop
ISO 40, 1/137 sec
Natural skin tones
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ISO 40, 1/928 sec
Colors are saturated but not excessively so.
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ISO 40, 1/938 sec
Some highlight clipping can occur in bright conditions.
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ISO 40, 1/33 sec
Low shadow noise levels
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Low Light, High ISO

Thanks to its fast F1.9 lens the Galaxy S6 Edge can keep the ISO down and/or the shutter speed up for longer. However, when the light gets really dim the new addition of optical image stabilization means that even at shutter speeds as slow as 1/10 sec you still have a very good chance of capturing a sharp image, just as long as there aren't any moving subjects in it.

In our real life testing the camera used ISOs up to 1250 which, in combination with the slow shutter speeds, allows for good exposure of even very dark night or indoor scenes. As you would expect, noise and the effects of noise reduction become more visible as you go up the ISO scale but the S6 Edge maintains a good balance between the two at all times. Pixel-level detail starts suffering a lot at ISO 500 but even at the highest ISO settings images are still nice to view at screen size. Chroma noise is very well controlled throughout the sensitivity range. 

ISO 80, 1/100 sec
Good detail and low noise
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ISO 200, 1/13 sec
Good detail but motion blur causes some softness on subject 
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ISO 320, 1/10 sec
Clean image with good edge detail
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ISO 500, 1/10 sec
Still some fine detail left in this ISO 500 shot
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ISO 640, 1/10 sec
Noise is getting more intrusive but well within acceptable limits
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ISO 1000, 1/10 sec
This image still works very well at smaller viewing sizes.
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Like the Galaxy Note 4 the Galaxy S6 Edge automatically switches to a multi-frame night mode when things get too dark. However, it is a little more hesitant to do so than its phablet cousin and uses higher ISO values in standard exposure mode. As you can see in the sample below, shot in a very dark gallery space, the image doesn't look too pretty at pixel level and the multi-frame mode has trouble capturing the animations on the red LED displays on the wall. However, many smartphones would not be capable of capturing a meaningful shot at all in these conditions.

Overall the the Samsung Galaxy S6 Edge is one of the best performing smartphone cameras in low light. You don't get the image detail of a hybrid device like the Panasonic Lumix DMC-CM1 or dedicated camera, but for a conventional smartphone this is as good as it gets.

Night mode
100% crop

Flash

Like the LED-units in all smartphones the S6 Edge's flash cannot compete with the Xenon flashes in proper cameras or the Nokia Lumia 1020. However, as far as LEDs go it does a decent job. Exposure can vary a little but is usually within acceptable limits. White balance usually does a decent job, even when flash is mixed with ambient light and the the flash mode tends to keep the ISO down which makes for decent image detail and low noise levels. It's still not much more than an emergency tool for social portraits in dark spaces, but the Galaxy S6 Edge flash is one of the best LED units we have used.

ISO 125, 1/24 sec
Good exposure and detail
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ISO 64, 1/30 sec
Slight underexposure
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