Merging two images into one document is fairly simple task in Photoshop CS5. Whether you are working to include multiple photos in one project or trying to overlay images, merging is a necessary skill. This tutorial takes you through the steps to accomplish this task.

  1. Open the two images you are working with in Photoshop.
  2. Select one the documents and click 'Image' on the toolbar across the top of the screen and then on 'Image size...".
  3. The image size panel will appear in which you can check the width and height of the image under Pixel Dimensions. Repeat this process with the second document and ensure that the two are of a similar size. If they are not, return to the Image Size screen and adjust number of pixels appropriately.
  4. Arrange the two windows on the screen so that both are at least partially visible with the image you want to transfer as the foreground on top. On the layers panel, located on the bottom right hand size of the screen, click on the layer labeled 'background' and drag it over to the canvas of the second image then release the mouse.

  5. The transfer image will now appear on top of the recipient image and in the layers panel, it will have appeared as "Layer 1" on top of the old background.
  6. From here you can change the size of the transfer image by selecting this new layer and select the Free Transform tool.
  7. To overlay images you can change the opacity of the transfer layer so that both are partially visible in the same document. Select the top layer in the layers panel on the bottom right hand side and click the drop down arrow next to 'Opacity'. A slider will appear which will adjust the percentage opacity of the layer, move the slider to achieve your desired opacity.