Lightroom 3 introduced a much better way to display a watermark by allowing positioning, multiline text options and images. We are going to use the image created in part 1 as a watermark.
In this case my image will be used as a desktop image for my home machine so I will use the specific dimensions of 1680 x 1050 for my output although this is not crucial, just make sure your image is large enough not to become overly distorted should it be scaled by the Finder. If you want to get really specific about the shape of the image frame then you can crop it to the absolute ratio. In my case 16.8 x 10.5 Enter those numbers as a Custom Ratio and crop the area of the image you want.
From the Export dialog enter the dimensions in the image size dialog. If you have fine text in your watermark you may want to set the Quality to 100. The resolution is irrelevant for this purpose. In the Watermarking section select Edit Watermarks…
Click the “Graphic” radio button then Choose. navigate to the png file you created in Part 1
In the Watermark Effects section we can change the opacity and position of the image. Since we already dealt with the opacity in Photoshop we can leave that set to 100%. The file I create was really large enough to command a significant portion of the screen so all I really need to do is scale it down. Play with this setting to see what works for your vision and your images. The Inset numbers will set the watermark away from the edges of the main image. This is useful to avoid clashing with the dock and task bar icons. The Anchor setting positions the watermark in one of nine locations on your image.
When you are satisfied with the size and position of your watermark save it as a new preset using the drop down menu upper left. (you can modify any of the settings later if you wish)
Export your jpg image. Use your operating system to set it as the background image. Now that your watermark is done you can change your image as often as you want in the same month. It is not necessary to keep the PNG file on your system.
Even if you dont do this for yourself it may be something a family member would like for their computer. Perhaps use a layer style to mark a special date. Dont forget to send something to your clients as well. Its just another way to keep your images in front of them, and in most cases it will be a surprise.