goobimama
Macboy
This tutorial is about the Depth of Field effect in Photoshop. Since Photoshop does not have any AI, it cannot distinguish the 3D aspect in a 2D image. So, it becomes difficult to get a realistic depth of field with normal blurring such as using the Gaussian Blur. Here’s a tutorial on achieving realistic depth of field (at least to me) using Alpha Channels. What it does is it creates varying levels of blurring giving it a more natural blurring.
The tutorial may get complicated and I don’t know if I’ve used the appropriate words, so if anyone can’t figure it out, lemme know.
Step 1: Open your image. For the trial round, open up an image such that it has two levels of depth, just so that you get the proper idea. The one I have is of my brother playing in the battle of the bands held two years ago. He looks much better than that…though not as good as me.
Step 2: Go to Window > Channels if you don’t have your channels palette open. Then, click on the “Create New Channel� button in the lower right corner of the Channels Palette. This will create a new channel “Alpha 1� and will fill the screen with black. Rename the Alpha 1 to “Main�.
*img339.imageshack.us/img339/3376/blur09gg.jpg
Step 3: Next, click on the right of “RGB� channel (As shown by arrow). Then, trace the Main part of the image with the brush tool. Painting “White� shows, and painting “Black� hides. The document will have a Red film over it and while you paint white the original will show.
*img339.imageshack.us/img339/3623/blur11jy.jpg
Step 4: After tracing the main focal part of the image, you have to select the sub focal part. Click on the new Channel icon in the Channels Palette. This will create a new Alpha Channel. Rename it to “Sub�. Then, while still on “Sub� channel, Ctrl+Click on “Main� channel. Then press Shift+F5 to bring up the fill window. Fill it with white. This will avoid retracing the main focal part.
Now trace the sub part of the image (in my tutorial, the second guitarist).
*img339.imageshack.us/img339/4318/blur23ei.jpg
Step 5: Now, create a new Alpha Channel and rename it “Final�. While still on “Final� Channel, Ctrl+Click on the “Sub� Channel. This will bring out a selection. Press Shift+F5 and fill it with 50% Gray.
*img339.imageshack.us/img339/6306/blur37sn.jpg
Step 5: While still on “Final� channel, Ctrl+Click on “Main� Channel. Then press shift+F5 and fill it with “White�.
Step 7: Now, in your layers palette, click on Background Layer and then go to Filter > Blur > Lens Blur. In this dialog box you only have to make sure “Final� is selected in the Source of the Depth Map. In my case, Final = Alpha 3.
*img339.imageshack.us/img339/4301/blur47fy.jpg
Move the Radius slider to whatever amount of Blur you want and the rest of the settings are individual preferences. (I added a little bit of ‘noise’)
If your main image is blurred while the background is sharp, just click on the main subject of the image. Sometimes, Photoshop takes the Black part to be as the sharp part…
*img339.imageshack.us/img339/3600/blur52oz.jpg
Hit OK and Voila! Notice that the second guitarist is only half blurred while the background is fully blurred.
Tips:
- If you want to have less blur for the “sub� image, then instead of selecting 50% Gray in Step 5, select Color and then use a lighter gray.
- While tracing the image, use a softness for the brush or it might give you very sharp and unrealistic edges. Use a high amount of softness when tracing the hair part.
- You can have more than two levels of blur, just work on the principles that Black hides, while white shows (shows = blurs). So just give them varying amounts of blur.
* I have blurred a few of the options and stuff in some of the images to reduce file size.
All comments appreciated.
The tutorial may get complicated and I don’t know if I’ve used the appropriate words, so if anyone can’t figure it out, lemme know.
Step 1: Open your image. For the trial round, open up an image such that it has two levels of depth, just so that you get the proper idea. The one I have is of my brother playing in the battle of the bands held two years ago. He looks much better than that…though not as good as me.
Step 2: Go to Window > Channels if you don’t have your channels palette open. Then, click on the “Create New Channel� button in the lower right corner of the Channels Palette. This will create a new channel “Alpha 1� and will fill the screen with black. Rename the Alpha 1 to “Main�.
*img339.imageshack.us/img339/3376/blur09gg.jpg
Step 3: Next, click on the right of “RGB� channel (As shown by arrow). Then, trace the Main part of the image with the brush tool. Painting “White� shows, and painting “Black� hides. The document will have a Red film over it and while you paint white the original will show.
*img339.imageshack.us/img339/3623/blur11jy.jpg
Step 4: After tracing the main focal part of the image, you have to select the sub focal part. Click on the new Channel icon in the Channels Palette. This will create a new Alpha Channel. Rename it to “Sub�. Then, while still on “Sub� channel, Ctrl+Click on “Main� channel. Then press Shift+F5 to bring up the fill window. Fill it with white. This will avoid retracing the main focal part.
Now trace the sub part of the image (in my tutorial, the second guitarist).
*img339.imageshack.us/img339/4318/blur23ei.jpg
Step 5: Now, create a new Alpha Channel and rename it “Final�. While still on “Final� Channel, Ctrl+Click on the “Sub� Channel. This will bring out a selection. Press Shift+F5 and fill it with 50% Gray.
*img339.imageshack.us/img339/6306/blur37sn.jpg
Step 5: While still on “Final� channel, Ctrl+Click on “Main� Channel. Then press shift+F5 and fill it with “White�.
Step 7: Now, in your layers palette, click on Background Layer and then go to Filter > Blur > Lens Blur. In this dialog box you only have to make sure “Final� is selected in the Source of the Depth Map. In my case, Final = Alpha 3.
*img339.imageshack.us/img339/4301/blur47fy.jpg
Move the Radius slider to whatever amount of Blur you want and the rest of the settings are individual preferences. (I added a little bit of ‘noise’)
If your main image is blurred while the background is sharp, just click on the main subject of the image. Sometimes, Photoshop takes the Black part to be as the sharp part…
*img339.imageshack.us/img339/3600/blur52oz.jpg
Hit OK and Voila! Notice that the second guitarist is only half blurred while the background is fully blurred.
Tips:
- If you want to have less blur for the “sub� image, then instead of selecting 50% Gray in Step 5, select Color and then use a lighter gray.
- While tracing the image, use a softness for the brush or it might give you very sharp and unrealistic edges. Use a high amount of softness when tracing the hair part.
- You can have more than two levels of blur, just work on the principles that Black hides, while white shows (shows = blurs). So just give them varying amounts of blur.
* I have blurred a few of the options and stuff in some of the images to reduce file size.
All comments appreciated.
