The Sony SLT-A55 was also thoroughly tested on technical aspects in the DIWA lab. The technical tests take place under standardized circumstances, in which the camera is extensively screened. We use these DIWA tests as a base and guide to complement our practical experience, and to have a secure way to be able to compare test results with those of previous models. The DIWA lab is a place where a condition is created through standardized circumstances, which allows cameras, compact and system cameras, to be compared with each other effortlessly. Additionally, the Sony Alpha 55 camera is used extensively in practice in order to assess control and photography aspects. Such a combination of lab and practical tests result in a thoroughly balanced, final assessment.
Sony Alpha 55 color reproduction
Many technical tests are performed in the DIWA lab, such as color reproduction in comparison with the Gretag Macbeth Color checker card. Measurements indicate that the Sony Alpha 55 has a fairly accurate color reproduction, with only a slight deviation from the Macbeth card. Up to 3200 ISO, the reproduction is the most constant, and at 6400 and 12800, it deviates a bit. It looks natural for the naked eye, and has fairly conservative color saturation. Contrast, color saturation, and sharpness can be adjusted in the ‘Creative Style’ menu.
Sony Alpha 55 - ISO values
Despite the 16 Megapixels high resolution, the Sony Alpha 55 performs very well in terms of noise in the high ISO values. The test shots taken with the Sony A55 in the lab and in practice show that the camera is able to shoot ‘noise-free’ shots, up to 1600 ISO. At 800 ISO, a slight increase in the signal/noise ratio can be observed, but you have to look very closely to find it. The amount of detail in the image is maintained. At 1600 ISO, we can see the effect of noise suppression a bit more, and some of the fine details are lost, but nevertheless, the shot is still fine for making a print. From 3200 ISO, noise suppression is strong and affects the general quality. Still, the result is above average, as only at 6400 ISO and higher do we throw in the towel. This is a remarkably good performance for a camera from this segment, with such a high resolution.
Dynamic range of the Sony A55
Another area, in which the Sony A55 performs remarkably well, is the dynamic range. Besides being able to adjust the settings via the dynamic range technology (DRO), the standard setting has an outstanding range. This DRO function has five different levels, from standard to powerful (level 5). Sony emphasizes especially the dark areas of a shot.
Any extra noise is then visible, but for a 16 Megapixel sensor, this is still very little. If you experiment a bit more with the DRO settings, you will notice that this depends on the scene that you use. Not all scenes benefit from the extra emphasis on dynamic range, but generally, this function gives the camera an added value.
Sony Alpha 55 kit lens
The Sony SLT-A55 comes with an 18-55mm f/3.5-5.6 kit lens included. With a zoom range of 3x, which is comparable to 27-83mm in a 35mm camera, this will most likely be a lens that will be quickly replaced with a greater zoom range. The lens suffers from corner softness at wide angle, which is not as strong at f/5.6, and is most optimal at f/8-11, in terms of sharpness throughout the entire focal range. Details are not completely sharp, but a bit soft across almost the entire range. This can be corrected with editing. The 18-55mm lens’ wide angle has even more problems. The 18mm range suffers a lot of chromatic aberration, which is certainly visible in the images with bright light and heavy contrast. The remaining focal points are clearly less affected by chromatic aberration.
Record wide-angle pictures with the Sony A55
Wide-angle distortion was to be expected, but the technical measurements and practice shots show a clearly visible distortion. The remaining focal points are not affected by distortion. It is apparent that Sony does not apply software correction editing in the camera itself. With the 18-55mm kit lens, it may be time to actively integrate this, as the competition shows that this is very effective and beneficial for the consumer. The general conclusion is that the Sony A55 kit lens is a cheap solution, and that especially the wide-angle shots suffer from the visibly inferior lens construction. The Sony SLT-A55 obviously deserves better and a replacement lens, with a greater zoom range, is desirable.