When the image in the LAB mode color mode is converted to the multi-channel mode, the created channel names are all Alpha; the advantage of the Lab mode is that it makes up for the shortcomings of the previous two color modes. RGB is between blue and green. There are too many transition colors between green and red, and too few transition colors between green and red.
When the image in LAB mode color mode is converted to multi-channel mode, the created channel names are all Alpha.
Lab definition
mode defines the most colors, is independent of light and equipment, and has a processing speed as fast as RGB mode, much faster than CMYK mode. Therefore, you can use Lab mode in image editing with confidence. Furthermore, colors are not lost or replaced when converting from Lab mode to CMYK mode. Therefore, the best way to avoid color loss is to use Lab mode to edit the image, and then convert to CMYK mode for printing.
When you convert RGB mode to CMYK mode, Photoshop will automatically convert the RGB mode to Lab mode and then to CMYK mode.
In terms of expressing color range, the first place is Lab mode, the second place is RGB mode, and the third place is CMYK mode.
It should be noted that many functions in LAB mode cannot be used in PHOTOSHOP.
The advantage of Lab mode is that it makes up for the shortcomings of the previous two color modes. RGB has too many transition colors between blue and green, and too few transition colors between green and red. CMYK mode loses more colors in the process of editing and processing pictures, while Lab mode has all of these aspects. compensated.
Lab mode is similar to RGB mode, the mixing of colors will produce brighter colors. Only the value of the brightness channel affects the light and dark changes of the color. Lab mode can be thought of as a two-channel RGB mode plus a brightness channel.
Lab mode is independent of the device. You can use this mode to edit and process any image (including gray image images), and it is as fast as the RGB mode and several times faster than the CMYK mode. Lab mode can ensure that the colors in the CMYK range are not lost when converting color modes.
If you convert an RGB mode image to CMYK mode, an intermediate step should be added to the operation steps, that is, convert it to Lab mode first. In the typesetting process of non-color newspapers, it is often used to convert images into grayscale images using Lab mode.
Related introduction:
Alpha channel (α Channel or Alpha Channel) refers to the transparency and translucency of a picture. For example, a bitmap stored using 16 bits per pixel may have 5 bits for red, 5 bits for green, 5 bits for blue, and the last bit is alpha for each pixel in the image. . In this case, it either represents transparency or not, since the alpha bit only has the possibility of two different representations, 0 or 1. Another example is a bitmap that uses 32 bits to store, and each 8 bits represent red, green, blue, and alpha channels. In this case, not only can it represent transparency or opacity, the alpha channel can also represent 256 levels of translucency, because the alpha channel has 8 bits and can have 256 different data representation possibilities.
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