Noise, resolution and sensitivity
These images show 72ppi (100% on a computer screen) sections of images of a resolution chart, captured using the Sigma 105mm f/2.8 macro lens.
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.
For a 16.1-million-pixel camera, the Alpha 37’s resolution performance is a little disappointing and lower than that for the NEX-F3 (perhaps due to the translucent mirror), although it more or less matches the scores of the Alpha 35 (AP 2 July 2011).
At its base ISO 100 it reaches 24 in JPEG and 26 in raw, which is maintained until ISO 1600 where the raw file decreases to 24. Noise levels start to increase above ISO 1600 and, as the noise reduction kicks in, on the JPEG at ISO 6400 the score drops to 22.
At the highest settings of ISO 12,800 and 16,000 performance is actually quite good, maintaining a score of 20 and 22 from the JPEG and raw files respectively.
Luminance noise is noticeable from ISO 6400 in the JPEG file, while raw images show luminance noise from ISO 800 and slight colour noise above ISO 6400, but this is easily removed.
Image: Overall detail is impressive from the Alpha 37 using the standard lens, with both raw and JPEG files delivering decent sharpness
