Tonal range (Tonal Range)

Tonal range (Tonal Range) digital cameras of tonal range means the description of the dynamic range of the number of tones. Dynamic range is not necessarily the tonal range wide dynamic range narrow tonal range does not necessarily narrow in the example below illustrates this problem: the tonal range wide tonal range narrow dynamic range, wide dynamic range narrow dynamic range of the sensor and the tonal range of the tonal range of the sensor (Tonal Range)

Digital camera's tonal range means the description of the dynamic range of the number of tones.

Dynamic range is not necessarily the tonal range wide dynamic range narrow tonal range does not necessarily narrow in the example below illustrates this problem: the tonal range wide tonal range narrow dynamic range, wide dynamic range narrow

Sensor dynamic range and tonal range

Sensor dynamic range and tonal range.

If a sensor dynamic range is 1000: 1, its AD converter at least 10-bit, it will have a wide tonal range. A 10-bit AD converter, sensor can output approximately 1,000 different colors, of course, the dynamic range of the sensor must not be less than 1000: 1-because the sensor complies with linear characteristics.

The image's dynamic range and tonal range

When you use the tone curve adjustments sensors linear data, you can see dynamic range and the tonal range is different and it seems to be an independent existence, with the use of tone curve, specific circumstances will vary.

Tone curve can compress the dynamic range, tonal range, or both.

When we take pictures in JPEG format, the camera will use high-contrast photos of tonal curve, which may damage the highlights and dark parts of the details-this is a congenital defect in JPEG format, if you want to avoid the loss of detail, can only use RAW format photos.

RAW image preserves the original image sensor and the entire dynamic range, so that users can use a suitable tone curve, compression, dynamic range and tonal range, to the most beautiful color and luminance output to the monitor, or photo print. The following illustration shows a picture of a 32-bit floating point image's dynamic range and the tonal range is compressed.

The monitor and printer of dynamic range and tonal range-the range compression

The monitor and printer have a limited dynamic range.

So we must use a tonal curve to compress photos in raw data in dynamic range, enabling it to adapt to a monitor or printer's dynamic range. The tone curve in the compresses the dynamic range of the process as possible to retain the details of the conspicuous. After this treatment, monitor or printer output images can make people feel beautiful.