Start learning with our library of video tutorials taught by experts. Get started
Viewed by members. in countries. members currently watching.
The elusive alpha channel remains one of the most misunderstood yet powerful tools in Photoshop. Alpha channels are collections of luminance data that control the transparency of an image, and they inform just about every aspect of Photoshop. As he builds transitional blended layers, fashions a depth map, makes edge adjustments, and takes on extreme channel mixing, Omni Award-winning expert Deke McClelland teaches Photoshop users that where there's a will, there's a way. Photoshop CS3 Channels and Masks: Advanced Techniques covers mapping texture on an image, turning flesh into stone, using vector masks, working with all different channels, creating a rustic edge effect, and much more. Exercise files accompany the tutorials.
Download Deke's customized keyboard layouts for Channels and Masks from the Exercise Files tab."
In the previous exercise, we created the Custom Wave effect using a displacement map but instead of getting nicely rounded waves, we end up getting this zigzag effect with these pretty obvious corners at this location here and around this location here and that's a function of our displacement map. I am going to go ahead and switch over to the Wave V.psd file and I am going to press Ctrl+H or Command+H on the Mac in order to hide those guides for a moment. What we are getting here, even though this looks like a sort of a nicely transitioning gradient, it's actually a combination of linear ramps. So we are going from gray at this point to black around here and we are just peeking at black, there is basically a single column of black pixels right about at this location and then we are ramping all the way to white and we have another single column of white pixels right about there and then we are ramping back to gray and so we have got a zigzag gradient going.
So it's no surprise it produces the zigzag effect. What we need is more of a Gaussian distribution to our gradient pattern here and a Gaussian distribution means that we are getting more rounded contours. So in other words, we would have gradually sloping, a gradually sloping gradient going away from the dark colors and then it would go more quickly in the gray area and then it would slow down again in the white area and remain slow until we go back to the neutral grays again. So it's basically more of a rolling hill pattern instead of these peaks and we can create a Gaussian distribution using the Gaussian Blur filter.
So I am going to press Ctrl+D, Command+ D on the Mac in order to deselect this image. I would like you to go ahead and open Wave we.psd. It's found inside of the Dmaps folder which is the sub- folder inside the 18_Displace_Maps folder and I am now going to go up to the Filter menu, choose Blur and choose Gaussian Blur and I am going to apply a big huge whopping radius, let's go with the radius of a 100 pixels. Now it's not going to look that different but it is going to make a difference in terms of the distribution of these luminance levels and I will go ahead and click OK in order to accept that modification.
Now let's go ahead and save this file out. So I want you to choose the Save As command and let's go ahead and save this new wave under the name Wave Gblur or something along those lines and then click on the Save button, make sure that you are saving in the native PSD format there. All right, now let's go back to this Rough trade.psd file that's included inside the 18_Displace_Maps folder and I am going to reverse the image by pressing the F12 key so we get our original American flag back. And I have got the background layer selected, I am going to go up to the Filter menu, I am going to choose Distort and I am going to choose Displace once again and we will work with the same values we worked with in the previous exercise, a Horizontal scale of 50 and a Vertical scale of 50 as well, stretch to fit, wrap around is fine.
Then go ahead and click OK and here we are inside that Dmaps folder which is inside the 18_Displace_Maps folder and I should say Dmaps is a sort of a short hand term for displacement maps. A lot of folks call them D maps and you will see it's spelled either D-maps or Dmaps like you see it here and then I am going to find that Wave GBlur file that I just created and you should have created as well and then I am going to click Open and notice that we get more of a rounded wave going this time around.
And I will go ahead and compare the zigzag by going up to the History palette, notice that I went ahead and saved out a snap shot here for the zigzag that we just saw a moment ago so this is what the zigzag looked like. Let's go ahead and hide those palettes once again. This is the zigzag version that was created using the standard linear gradients and this is the new rolling version which is a function of having applied that Gaussian Blur filter. So Gaussian Blur goes ahead and rounds off the contours of any displacement map, realize that you have it as part of your arsenal, also remember here that even very large Gaussian Blur values produce fairly subtle effects. If you wanted more rounding, you would want to apply a higher value still.
All right, in the next exercise, we are going to take a look at what happens when you apply a two channel, actually an RGB but two channels as you will see, displacement map to the same American flag.
There are currently no FAQs about Photoshop CS3 Channels & Masks: Advanced Techniques.
Access exercise files from a button right under the course name.
Search within course videos and transcripts, and jump right to the results.
Remove icons showing you already watched videos if you want to start over.
Make the video wide, narrow, full-screen, or pop the player out of the page into its own window.
Click on text in the transcript to jump to that spot in the video. As the video plays, the relevant spot in the transcript will be highlighted.