Photoshop - Non Destructive Matting using Channels

Here is an example of Non destructive masking using the channels panel to help. For this example, we will remove the sky background from this chicageee image ...



Step 1: Open your photo... :)




Step 2: Click on the channels tab and search through each channel to see which one gives you the best contrast difference between the objects you want to matte out. In this case, the BLUE CHANNEL works great for this particular image. (1) Drag the blue channel down to "Create New Channel" icon. (2) is created



Step 3: while the "blue copy" or the channel you copied is selected, go to IMAGE | ADJUSTMENTS | LEVELS




Step 4: Adjust the levels to blow out the lights or darks. You don't want to go to hard because you still want some of the fine details, for example the flag poles in this image. The idea here is to get a really good separation line between the 2 items.



Step 5: Now that we have a good amount of white, its time to blacken out the opposite area. We can do this very quickly by making a selection and filling in the dark area with black. lets start by selecting the magic wand and select the white area.



Step 6: Inverse the selection, press SHIFT + f5 to pull up the FILL command. YOu want to make sure that BLACK is the foreground color... then click OK.

**** NOTE, you can also use the PAINT BRUSH on this channel to add or remove some details.. use black and white and or feathered brushes.. *****



Step 7: This is the result after the fill.



Step 8: Turn the RED, BLUE and Green channels back on and turn off the BLUE COPY layer.



Step 9: Lets go back to the layers panel and now lets LOAD the selection we just created. From the file menu go to SELECT | LOAD SELECTION



Step 10: Choose the channel you want to select from.



STEP 11: Make sure your selection is right. You MAY need to inverse this selection. In this example we needed to. If you wanted to avoid this step, in step 10 there is an INVERSE check box... you could just select that and you'd skip this step all together.



STEP 12: while the selection is still active, click on the "ADD LAYER MASK" (1) and it will create a Matte on the layer (2). The

The rest of the image is not deleted, but rather is is masked away on this channel. You can still modify the matte by clicking on the image on the layer that represents the matte and paint using the paint brush, black or white. Black makes 100% transparent, white makes it 100% solid. Anywhere inbetween white and black adds opacity to the image.