A channel is a kind of constituency (please understand it this way for now, I know this is not comprehensive)
Let’s first understand the classification of channels
1. Color channel 2. ALPHA channel (including fast mask)
3. Spot color channel <BR> First, let me explain to you the color channel as an example. After a picture is created or opened, a color channel will be automatically created. For example, create or open a color mode of R (RED) G (GREEN). Green) B (BLUE blue) picture you will find four channels on the channel panel.
A total channel (that is, the channel of red, green and blue synthesis. What everyone sees on the screen is this synthesis channel. CTRL+~ can open it. It is selected by default). The next one is the R (RED) channel. G (GREEN green) channel B (BLUE blue) channel .
Now if I open a picture with the color mode C (CYAN) M (MAGENTA) Y (YELLOW) K (BLACK), I believe you already know how many channels will appear.
Now that you understand the concept, it’s time to tell you what the color channel is used for. It tries to give you a distribution of a certain color (the professional point is the color scale or hue, which is the gradient of the color from the darkest to the brightest. The number of times you enter the ladder, I know it is difficult to understand, so I try to introduce it to you in the form of color distribution). It uses a black and white grayscale image to represent the color distribution. The darker the place, there must be a certain color distribution. The less, the darker the color (i.e., the smaller the hue value, the lowest hue is 0, you don’t need to remember these in particular, you will naturally understand what I mean with the more exposure you have), and on the contrary, the whiter the color. It is certain that the more a certain color is distributed, the brighter the color will be (that is, the larger the hue value, the highest hue is 255). Maybe you will wonder why it is represented by a black and white grayscale image, why not directly use a certain color Isn't it more intuitive? Well, you have entered the formal stage. Let's continue to look down. Because the eyes often deceive everyone, a black and white picture can directly tell the depth and lightness, and a picture similar to the one below can tell the difference. The red of that piece is redder or in other words darker, and the red of that piece is further away from red or lighter.
I think only those who have specifically studied "color science" can know it (I can't see it anyway, but if you want to strongly request to use primary colors to display channels, you can do the following operationsEDIT(edit)--- PREFERENCES---DISPLAY & CURSORS(display or cursor)---check COLOR CHANNELS IN COLOR (channels are displayed in primary colors), then you can display channels in color, but I do not recommend you to use this)
Another point is that the order and name of the color channels cannot be modified. Now everyone should have a deeper understanding of the color channels.
Note: I use --- to connect the menu and its sub-menus and related options. Well, it’s already two o’clock in the night, and today is my birthday, so I think it’s been more than two years since it was a classic, and I haven’t written anything yet. I am really ashamed that I wrote my first tutorial on this special day. Anyway, I hope it can give you a little inspiration. Please point out any mistakes. I will finish it as soon as possible.
The color channel will be discussed first. If you have any questions, please ask them in the post. I will take the time to answer them one by one.
In the last section, you all have an understanding of the color channel. I hope it is the color distribution in your mind, and that's right.
It's time for us to understand a more powerful thing, "ALPHA channel or mask". Let's first look at the quick mask, which is a special form of mask. Its function is to quickly create a complex selection, but there is Disadvantage: This selection cannot be saved together with the image. The selection you have worked hard to draw (note that I am talking about drawing, you will understand what I mean below) cannot be saved. And it can only create one. It is really Inconvenient, right? So it’s best not to use it, use masks. But you should also know it. When someone asks you for quick masking, you will be glad that you know it and know that there are many shortcoming.
So next, learn to create a quick mask that is not very useful. I'm sure you understand what I mean. Before we create a quick mask, we must create a selection, and then use the shortcut key (Q) QUICK MASK to enter the quick mask. In the editing state of the mask, you will see an area surrounded by light red.
Yeah. I don't like this color either, so I'm going to change it to a color I like, double click on the quick mask channel and a quick mask options dialog box will appear.
Just change it to the color you like, but it's best to be a little different from the original color, otherwise you won't be able to see the mask clearly.
By the way, if you change the selection area under the color indicator, the picture will look like this, covering the subject.
So you generally select the mask area above. In the channel panel, you will see an additional channel called QUICK MASK, and that's it. If you don't have a selected selection, I believe you will see something like this. , and the channel panel will appear like this.
So you should create the selection before creating the quick mask.
Okay, let’s start editing this quick mask. It’s actually very easy. You can paint directly with a black or white brush. The function of the black brush is to increase the mask and reduce the selection; the function of the white brush is to increase the selection and reduce the mask. ; Make sure you remember this rule, it's important.
Now is the most critical time. We can get the constituency right away. This is really exciting. Don’t we just want the constituency? Follow me.
Draw a selection, great! This is the quick mask we introduced in the last section, glad you can understand it.
In this section we introduce the most important ALPHA channel (i.e. mask). I think everyone should have a perceptual understanding of the ALPHA channel (i.e. mask, from now on I will call it mask) after studying in the previous section. Since quick mask is a special form of mask, it definitely has the advantages and functions of mask, which is to draw a selected area. However, it also has the advantage that quick mask does not have, it can be saved with the image; OK , you should now know why it is recommended that you use a mask instead of a quick mask; because it can be saved with the image, the next time you open your picture, the hard-drawn selection can be edited again, which is very convenient. It can also be created Multiple (quick mask can only create one), so you can use the addition, subtraction, and intersection of selections to create more complex selections (this will be introduced in detail later)
When creating a mask, you do not need to create a selection first, which is more convenient than quick masking. Just open the channel control panel and select the third button to create a mask.
Once it's created, all we have to do is edit it. Well, that's easy. Because it's exactly the same as editing a quick mask, I'm sure you already remember the two rules I mentioned.
Okay, now comes the most essential part of the ALPHA channel.
We create two ALPHA channels, one selection is square, and the other selection is elliptical. Just like this
It’s better not to overdo it. I can’t find a more understandable explanation for LOAD SELECTION & SAVE SELECTION, so I’ll leave it blank for now and finish writing the spot color channel first.
Sorry, my thoughts are starting to get a little confusing. I really want to explain the essence of the ALPHA channel in a more popular and easy-to-understand way. But I can't do it. It has something to do with my mood. It seems that I still need to put some effort and time into sorting it out. I can think and adjust my messy mood. I'm sorry everyone. Please understand. Thank you for your understanding!!! I will recover soon and complete my unfinished things.
ABOUT spot color channel (SPOT COLOR CHANNEL) Okay, the previous section introduced the most important ALPHA channel among the channels. This section introduces the spot color channel (SPOT COLOR CHANNEL). Some books may call it a composite point color channel. It refers to a special mixed ink, especially in that it is not included in the four printing inks of CMYK. Mixing means that it is synthesized from several inks and is added to CMYK ink when printing. When the film comes out in the printout center, there will be an extra film, and this is it. It can only be found in the channel control panel menu (NEW SPOT CHANNEL to create spot color channels).
Or just use shortcut keys. As mentioned before, the channel control panel creates an ALPHA channel by default. If you hold down CTRL and try again, what will pop up? Is it a dialog box for creating a spot color channel? Just remember there are two kinds, you won’t find them on the menu.
For example, I create a spot color channel like this
Now we open the channel control panel menu and find (MERGE SPOT CHANNEL merge spot color channels),
Its function is to add the spot color channel to each color channel, so that you can see the effect after printing very accurately, and you can also save a piece of film, right? Look at the other color channels. What has become.
There is also an ALPHA channel that can be converted into a spot color channel. Double-click the ALPHA channel and you will see a dialog box like this,
You may be familiar with it. At the bottom are the settings for the spot color channel, including ink color and transparency.
This is what the spot color channel looks like. It's amazing. However, this channel has a lot to do with printing, so few people come into contact with it, including me. Please correct me if there are any mistakes.
