This tutorial will provide some tips on creating a digital watermark, making alpha channels and using layer adjustments. There are endless variations on this so it would be in your best interest to give yourself time to experiment and play around with settings you like.
1. Prepare a graphic to use in your layout. Preferably the image will be a high contrast grayscale graphic (lots of black and white with minimal gray tones). This can be achieved using IMAGE menu > ADJUSTMENTS > LEVELS and bringing the black and white points towards the center or using IMAGE menu > ADJUSTMENTS > THRESHOLD and playing with the threshold slider.
2. Place or copy the graphic you want to use as your watermark into your layout. Move, rotate or scale the image to its desired location.
3. If you have placed the image, you will need to rasterize the image prior to the next step. LAYER menu > SMART OBJECT > RASTERIZE or LAYER menu > RASTERIZE> SMART OBJECT.
4. Fill the entire background of the layer holding the graphic with white. EDIT menu > FILL: use WHITE, blending BEHIND. This will put white pixels behind the graphic as if you painted on the backside of a piece of glass.
5. Select the entire layer – SELECT menu > ALL or command/ctrl+A and cut it from the document – EDIT menu > CUT or command/ctrl+X. Delete the placed objects layer which will now be empty.
6. Go to the channels panel, make a new alpha channel and EDIT menu > PASTE or command/ctrl+V into the new channel.
7. Invert the channel – IMAGE menu > ADJUSTMENTS > INVERT or command/ctrl+I. This will make a proper alpha channel where white represents editable areas and black will be protected areas.
8. Load the selection – SELECT menu > LOAD SELECTION: channel ALPHA 1 (or whatever you may have named it) You can also quick load the selection by command/ctrl clicking on the alpha channel thumbnail.
9. In the LAYERS panel make a new Solid Color Adjustment layer. This will allow you to dynamically change the color of the watermark throughout the editing process, it will also use the selection as a mask specifically for that adjustment layer. Use the eydropper tool to sample the background color and then adjust the color to make a low contrast watermark.
10. The EDIT menu > TRANSFORM tools can be used to further move, scale, rotate, skew, etc… the graphic.
11. Further color adjustment can be made by double clicking the solid fill thumbnail and adjusting the color.
