With the focus on Sony’s SLT technology-wielding Alpha 33 and 55 cameras, have we all been passing over a perfectly capable DSLR? Sony offers up the Alpha 580 for your consideration
Noise, Resolution and Sensitivity
The 16.2-million-pixel sensor records images with good detail and maximum file sizes of 4912×3264 pixels, which is good enough for A3-sized prints. Luminance noise is noticeable at ISO 800, although images at up to ISO 1600 are usable. The highest sensitivity of ISO 12,800 can be expanded to ISO 25,600 using the multi-frame noise-reduction mode. In this mode the processing time is roughly two seconds to combine the multiple images into one low-noise image.
Resolution detail is impressive. In JPEG files it reaches up to 26 at ISO 100 and 24 at ISO 200-1600 on our charts. Raw files reach 26 up to ISO 400, with a minor drop to 24 at ISO 1600, so it’s worth shooting raw files for best results. Images shot at ISO 25,600 in multi-frame noise-reduction mode are noisy and show less contrast, but resolved detail reaches an impressive 18 on our charts.
Resolution charts: These images show 72ppi (100% on a computer screen) sections of images of a resolution chart, captured using the kit lens set to 50mm (75mm equivalent). We show the section of the resolution chart where the camera starts to fail to reproduce the lines separately. The higher the number visible in these images, the better the camera’s detail resolution at the specified sensitivity setting.