Sony NEX-C3 Concise Review
Auto HDR / DRO
Auto HDR is only available when shooting in JPEG mode, and allows automatic exposure bracketing up to 6EV. The final HDR images are achieved by combining multiple exposures (one normally exposed, one over exposed and one under exposed.) This allows for a larger dynamic range to be recorded than the sensor is capable of capturing alone. One of the downsides to shooting and processing HDR in-camera is that you have no control over the tone-curve applied. However the default tone curve that is applied by the C3 in-camera produces acceptably realistic looking results (in all but the most extreme DR scenes) even when processing an image with a 6EV bracket. When shooting in HDR mode the camera saves the HDR image along with the normally exposed image.
Dynamic range optimization (DRO) attempts to do the same thing as Auto HDR, creating a single image containing a large range of brightness in a way that looks natural to the human eye. Instead of blending multiple images at different exposures, DRO applies sophisticated series of tone curves to each area of similar local brightness within a single image, in an attempt to balance details in the shadows while maintaining local contrast. This method can be more effective than applying a homogeneous tone curve to the entire image in post processing. For a more in-depth explanation of how the system works please take a look at our 2009 article about the technology behind DRO.
|HDR Auto||HDR Off||HDR 1EV||HDR 2EV||HDR 3EV||HDR 4EV||HDR 5EV||HDR 6EV|
|DRO Auto||DRO Off||DRO Lv1||DRO Lv2||DRO Lv3||DRO Lv4||DRO Lv5|
DRO has the benefit of being faster than Auto HDR, (no significant in-camera processing time is required) and can be used while shooting in RAW (and RAW+JPEG) modes whereas Auto HDR is a JPEG-only function. However, DRO does not provide the same level of highlight and shadow recovery as Auto HDR, as you can see from the illustration above. In this scene, DRO has a significant impact on shadow brightness, but very little impact at all on the highlight areas. When shooting with DRO enabled in RAW, the DRO is applied to the RAW file which is quite beneficial as it makes a noticeable impact when trying to bring up the shadows during processing.
Auto HDR, on the other hand, is able to pull down the brightness of highlight areas very effectively. Both HDR and DRO have their own unique drawbacks. Since HDR images are created from multiple shots blended together, ghosting can be evident if you are photographing a moving subject. And because DRO images bring up dark midtones and shadow areas by applying a tone curve, noise will become more visible in the shadows. However, the low-light capability of recent sensors makes this less of an issue.
Hand-held Twilight mode
Hand-held twilight mode functions by taking a series of images in rapid succession, then blending them into a single image. The reason for doing this is that high ISO noise is a random phenomenon and as such, is found in a different pattern in each frame. By combining these frames it is possible to remove much of the noise commonly seen in images shot at high ISO settings, whilst maintaining the visual integrity of the common scene elements.
Here we are comparing the same scene shot at ISO 6400, 12800 and in Hand-held twilight mode (EXIF recorded as ISO 1600) without a tripod. As you can see, the Hand-held twilight mode produces a final image with significantly more detail retention and less visible noise than when shot at high ISO settings.
|Hand-held twilight||100% Crop|
|ISO 6400||100% Crop|
|ISO 12800||100% Crop|
Hand-held twilight mode can't compete with long-shutter tripod mounted shots in terms of critical image quality, but it works very well for all those times when setting up a scene with a tripod is impractical. And when compared to higher ISO settings of 6400 or 12800 you may actually be served better using Hand-held twilight mode.
Anti-motion blur works in a similar way to hand-held twilight mode but instead of high ISO noise it is designed to reduce motion blur in situations where a high shutter speed might be impossible. It does this by capturing multiple exposures and combining them to create a single, sharper image. When shooting in this mode, exposure compensation is the only method of adjusting exposure, as the camera automatically sets the shutter speed and aperture. Because this feature works by analyzing and blending multiple images, it is impossible to predict precisely what the final image will look like.
At small print sizes the final result is quite convincing, but when viewed at 100% it is possible to see significant artifacting in the areas where motion was compensated for. Overall, Anti-motion Blur does a perfectly respectable job, and can make a significant difference to image quality in small prints and web use, but very often images don't stand up to critical scrutiny. For more information about this function and examples of its effectiveness, take a look at our Sony NEX-5 review.
Like the original NEX-3, the NEX-C3 shoots at a maximum video resolution of 720p at 30fps (actually the industry-standard 29.796 fps) in MP4 format. Just like the NEX-3 the C3 cannot record video in AVCHD format. Continuous AF is possible during movie recording, although is not always quick to respond, especially in low light. The results are fairly good, and although there is some rolling shutter it's no more apparent than what we would usually find in sensors of this type.
Whichever aperture setting you choose in aperture priority mode, manual mode or using iAuto's 'Bkgrnd Defocus' option, this is retained while shooting video. In all other modes the aperture is controlled by the camera. With E-mount (NEX) lenses, the aperture will adjust during the video to help maintain correct brightness (though giving the user no control over depth-of-field). With A-mount DSLR lenses the aperture is set (either manually or by the camera) at the beginning of the video and maintained regardless of the change of brightness - limiting the camera's ability to respond to big changes in light level.
Movie sample 1
This video was taken at a focal length of approximately 80mm (equivalent) using the kit 18-55mm lens. The built-in stereo microphone is quite susceptible to wind noise as you can hear in this video, but this is no worse than most built in mics. Sadly though, unlike many of its competitors, the C3 does not offer a wind-cut option.
In terms of image quality, this clip is decent without being outstanding. Exposure is accurate and color is pleasant, but this panned shot isn't as smooth as we would like. We can't help but feel that Sony has deliberately limited the C3's video specification, and it's a shame. It is worth noting the Cyber-shot HX9 boasts a much better (1080 60i/p) video mode than the C3, albeit with less depth-of-field control.
|1280x720p, MP4, 13 sec. 13.45 MB Click here to download original .MP4 file|
Movie sample 2
The dynamic range of the C3's sensor is beneficial when recording video as well as stills. The shadow detail in the foliage in this clip is well preserved without clipping too much on the waterfall's highlights. Artifacting is slightly visible in the fast moving water, however we would expect from a video with a bit rate of 9362 kpbs - fairly average for this type of file. The high audio frequency of the waterfall is somewhat overpowering in this video but can be easily remedied in almost any video editing software.
|1280x720p, MP4, 21 sec. 22.73 MB Click here to download original .MP4 file|