Samsung seems to use the 10x zoom as the primary sales argument for the S4 zoom. I'm not too much interested in zooming myself. I even sold the 70-300 zoom lens for my DSLR since I rarely use those focal lenghts. Most picture are wide to normal, in a range of 24-50mm. This is why I'm very excited to see a wide 24mm lens on the S4 zoom. It's not really the same diagonal field of view as a 24mm full frame camera, since the S4 zoom delivers a 16:9 image instead of the classical 3:2 format.
For this test I did not try the zoom and I focussed on the following aspects:
- pure image quality: sharpness, distortion, color rendition
- exposure, contrast and color balance. You can adjust these things in postprocessing, but that makes it tedious.
- focussing: does the camera focus correctly after indicating the correct point of focus.
- jpg quality: since all 3 camera's lack a RAW mode, the built in software applies a tone curve, sharpening, noise reduction and (for the Panasonic) even a stretch function to minimise lens distortions. I'll evaluate if the files are not over processed.
I decided to test the smartphone/compact against a smartphone (my current Google LG Nexus 4) and a low end compact camera (my Panasonic DMC-FS40). This test is without any image post processing. I already did a test to compare the Panasonic against the Nexus 4, which gives different results.
Below you will find 6 test images. Each image represents a specific challenge. If you want to download all full resolution images, download them from Flickr. Note that during this review I am comparing on 100% size, which is showing the individual pixels captured by the camera's. This is not really fair, since the camera with the least pixels (8Mpx Nexus 4) will appear to be on equal foot with a camera that has more pixels (16Mpx). In reality, if the images at 100% look equal, the 16Mpx will show twice as much detail as the 8Mpx camera. To further add to the confusion the 24mm wide lens of the S4 zoom captures a wider image. The result of this is that the higher pixel count of this camera is spread out over a broader scene. The consequence is that the 100% cutouts will show about the same image magnification, despite the higher pixelcount of the S4 zoom.
You will each time see an overview comparing the images from the 3 camera's, followed by one or two detail images. The Nexus 4 is always to the left, the S4 zoom is in the middle and the Panasonic is on the right.
1) outdoors, good light (warm morning sunlight)
This is the easiest shooting situation. Almost every camera can produce a good image in these circumstances: iso can be kept low, shutter speed can be high so there is no camera shake and the diaphragm can be closed. I adjusted these settings manually to get the best possible image quality out of the cameras.
We see that the Nexus 4 looks the sharpest. This is because it applies quite heavy sharpening. The Panasonic looks unsharp. When you look at the bricks, you see that too much noise reduction is applied, even at it's lowest iso setting. The S4 zoom shows the most detail on 100% enlargement. It looks a bit softer than the Nexus 4, but this is because the sharpening has been kept within more reasonable limits. It does render the scene too yellow, however (note that this was in warm morning light).
The corner detail image is interesting: it appears the S4 zoom is very unsharp here, but this is due to a lower depth of field thanks to the larger image sensor. That is a bit surprising, since I used the smallest diaphragm (the S4 zoom only has 2) and a broader field of view. But apparently the sensor is that much larger than the one in the Nexus 4 that it is still having a lower depth of field. This is actually a good thing when you want to zoom in (that's what the camera is intended for, after all) and isolate a subject or take a portrait.
2) outdoors, medium light (rainy afternoon)
In this image, we already see some more differences appear. It becomes even more apparent that the Panasonic is soft. Even more noise reduction has been applied by the camera to battle the high sensor noise at this higher iso. It is clear now (look a the pavement) that the S4 zoom has more sharpness than the Nexus 4. There is also more detail, as you can see in the streaks the rain left on the hood of the car.
I added an image of the corner again. The lamppost still falls within the depth of field. You can see that this time the corner sharpness of the S4 zoom is higher than the Nexus 4. This proves that the unsharpness in the first image was due to DOF. The Panasonic shows some chromatic aberration on the lamppost, even tough there was no sun to be seen (conditions were very overcast).
3) indoors, very low light
Ouch. This is where all 3 camera's show their limits. The light was very dim, pushing the iso settings all the way to the top. The Nexus 4 shows more image noise than signal and definately lost here. The Panasonic holds up well this time, masking it's unsharpness behind the noise. The S4 zoom wins out, showing the best colour saturation and contrast with the least amount of noise. Due to more built in softening (to mask the noise) the sharpness is no longer optimal, which is to be expected in these conditions.
4) indoors, very low light with flash
This image is taken in the same bad conditions, but with flash. Although the Panasonic has a decent flash it still decided to use a high iso setting. The result is a well-lit, but grainy image. The LED flash of the Nexus 4 doesn't cut it at this distance of 3 meters. The image is a lot better than the one without flash, but sharpenss is gone and noise is all over the place. The Galaxy S4 zoom gives a very good image. No colour casts, no washed out highlights and still a nice balance with the background. It remains of course a flashed picture, which always kills the mood a bit and can give red eyes. But remember you can always take the same picture without flash with the S4 zoom, even in the worst indoor lighting conditions.
5) outdoors, bad light (just before sunrise)
The 3 camera's show similar exposure, contrast and colour rendering in this image. All 3 manage to save the mood of the scene. There is not much light, but even the low amount of light just before sunrise is enough to keep all of the 3 contestants out of the danger zone. Again, the Panasonic is softer, the Nexus 4 applied more sharpening. For the S4 zoom I zoomed in a bit and it seems like this was enough to make the S4 zoom lose it's slight lead in pixel-per-pixel detail. I'll evaluate the impact of the zoom further when I write the full review of the Galaxy S4 zoom.
In the detail of the roof and the border of the chimney with the sky we see that the Nexus 4 exhibits some chromatic aberration. We also see how much unsharpness the Panasonic shows outside of the center. Not only does it have a bad sensor, but it also seems to have a bad lens. The S4 zoom shows almost no chromatic aberration.
6) macro, good light
The S4 zoom is clearly the best at macro distances. The other two camera's were taken as close as they could focus, showing their highest image magnification. The S4 zoom could go so close that the lens would shade the whole image, but I didn't do this in order to have an image that we can compare to the other camera's. It can actually focus to about 2 cm from the lens. Strangely enough, it can only do this at the widest zoom setting. If you zoom in, the image magnification that is possible soom becomes much less. Nevertheless, this is an impressive macro performance of the S4 zoom. The diameter of the puppet is about 4cm.
Conclusion
The Galaxy S4 zoom is a clear winner. Low noise, good sharpness and detail. Exposure, contrast and saturation are about where I like them (not over the top). Image sharpening and noise softening are also within reasonable limits to still allow for postpocessing. High iso's perform better than on smaller sensors.
It's doesn't produce DSLR quality and an advanced compact will beat it's image quality. It is about on par with a medium level compact camera. The Panasonic DMC-FS40 performs bad. It's images are noticeably unsharp and image noise pops up quickly when the iso is raised. The Nexus 4 shows it has a decent smartphone camera, provided the lighting is right and you might want to bump saturation and contrast in postprocessing.
I remind you again that this review is comparing camera's on a pixel-by-pixel basis. The Galaxy S4 zoom has more pixels than the other camera's, so it will give you much more detail when you look at the whole image file.
No comments:
Post a Comment