Noise, resolution and sensitivity

These images show 72ppi (100% on a computer screen) sections of images of a resolution chart, captured using the Panasonic Lumix DMC-FZ200’s lens set to 105mm. 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 is at the specified sensitivity setting.

With a small 12.1-million-pixel sensor, the Lumix DMC-FZ200 just about manages to resolve up to 24 on our resolution test chart. This is about as much detail as could be expected, and is on a par with other 12-million-pixel models we have tested, whether DSLR or compact.

As the sensitivity increases, the resolution starts to drop quickly. Luminance noise and the effects of noise reduction start to take their toll on the resolution of JPEG images, and by ISO 400 the FZ200 reaches just 20 on our chart. By the time the maximum ISO 6400 setting is reached, a resolution of only 16 is achieved, with luminance noise very apparent. There are also signs of magenta and green colour noise, although it would appear that heavy colour noise reduction has also caused the image to become desaturated and to lose contrast.

What is far more important, though, is  how real-life scenes are rendered. For the most part, the high-sensitivity settings will not be used and I found there were only a few images, such as when shooting athletics at the Paralympics, that warranted me increasing the sensitivity beyond ISO 800.

At the lower sensitivities of ISO 100 and 200, images are as detailed as can be expected, but have a hint of luminance noise, although nothing of too much concern. It was at ISO 800 that I found the tipping point. Above this, the noise reduction really kicks in, and images have blurred and smudged areas, with odd oversharpened-looking pixels. While this is not a concern when viewing on screen or for small prints, those wanting to make decent-sized prints should aim to stick to ISO 100 for best results. Of course, the FZ200 isn’t alone in having this type of image quality or noise reduction, as it is common among nearly all compact cameras.

Shooting raw images does allow far more control in post-capture editing. At the moment, Adobe Camera Raw does not support the Panasonic RW2 file format from the FZ200, so for now images must be edited using the bundled SilkyPix Developer Studio software.

I find this software a little awkward to use, although with patience it does produce good results. Colour noise can be reduced significantly, and compared to a JPEG image, raw files can be sharpened a bit more, although little extra resolution is revealed.

Image: The 600mm equivalent focal length is ideal for wildlife images, and if you don’t mind luminance noise, slightly more detail is seen in raw files compared to in-camera JPEGs

Pages: 1 2 3 4 5 6 7 8 9 10 11 12