How to add spot color in Photoshop

Spot colors are often used in prepress production. Adding spot colors to FreeHand, Illitrator, and other typesetting software is very simple, but if you need to add spot colors to Photoshop images, such as an advertiser requesting an image in an ad The object is clearly expressed to achieve the purpose of highlighting the topic. How do you do it? Prior to the introduction of Photoshop 5.0, adding a spot color to the image was a real headache, but with the continuous upgrade of Ptotoshop software, Adding a spot color to an image now is as easy as creating a new channel. The following author takes Photoshop 6. O, for example, briefly introduced how to add spot color information in the image, hoping to help the peers.

I. Preparation

Before starting work, we first met the channel and DCS format in Photoshop.

1. Channel: This is a basic concept in Photoshop. It has two uses, namely the storage of image color information and storage selection range (Figure 1). The display of information is related to the color mode of the image. For example, images in the CMYK mode have cyan, magenta, yellow, black, and synthetic channels, while images in the RGB mode have only red, green, blue, and synthetic channels. In Photoshop 5. After O, the channel can also save spot color information at the same time, so it is very simple to add spot color in the image.

2. DCs format: DCs is an acronym for Desktop CoIor Separation, which is the desktop color separation format. This format can store the file as a single-color file of C, M, Y, and K, that is, the image file is divided into four color files. The advantage of storing the DCS format is that the Postscript interpretation is fast at the time of output, and it is flexible to use monochrome files. Storage DCS 2. O format dialog includes preview, DCS form, encoding and other options (Figure 2), of which the most options are the preview and DCS format. The preview is just the display color of the header file, which has no effect on the actual color; for the DCS type, if it is a monochrome file, only one color file is generated; if it is multiple files, a header file and four color files are generated, total 5 Files. When importing or opening a header file, the entire image is then linked to the page.

3. If you want to get the best spot color effect, but also to do the following research and plans: 1 to determine whether the spot color image needs to be hollow; 2 spot color ink overprinted on other inks, how to prevent the appearance of moire; 3 if you want to Color image import layout software, how to save spot color image file as Photoshop DCS 2. O

Second, join the spot color information

There are three ways to add a spot color channel to Photosh0p: 1 Create an empty spot color channel; 2 Create a spot color channel; 3 Convert a Alpha channel to a spot color channel.

1. Create a spot color channel

First, open the channel panel and select the new spot channel in the channel panel menu, which will generate an empty spot channel; if you want to select the image as a new channel, create a selection on the image, and then from the channel panel menu Select the new spot color channel command; if you want to turn an AIpha channel into a spot color channel, first select the channel you want to convert, and then select the channel option from the menu in the channel panel. Select the spot color in the pop-up dialog box. (Figure 3).

2. Determine spot color

If the spot color channel is newly created, you can click on the color sample in the New Spot Channel dialog and select the color from the color library; if you want to turn an AIpha channel into a spot color channel, click on the color sample in the channel panel. You can choose the color. It should be noted that the effect of the spot color on the display is not very consistent with the effect printed on the paper, because it is easy to accurately preview the color on the screen. The colors in the color library are the manufacturer's standard color patches.

3. Specifies the hardness of the spot color (transparency)

In the Density option, if you enter a small value, you can achieve a transparent, high-gloss spot color effect; if the value is larger, it is an opaque spot color effect (the density option only affects the transparency of the spot color. However, no new color will be produced. That is, the hue of the spot color will not be changed.) If you want to display the spot color in the channel, you can click on the menu "Edit a Preset", select "Display and Cursor", and then select the "Channel with primary color display" option.

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