You can ask Photoshop to blend two or three similar images seamlessly with the Auto Blend function.
I will use three free stock images of *mjranum-stock Marcus J. Ranum to demonstrate it.
These are the three free stock images.
Step 1 : Go to File>New
Step 2 : I have set the size of the document fairly high at 11 inches wide and 9 inches high.
I have set the resolution at 300 pixels to make it suitable for printing. I have set the Background Contents to Transparent.
Step 3 : Click the Move Tool.
Step 4 : Keep SHIFT pressed while moving the images to the Transparent Document.
Step 5 : The image is quite large. It moves to the centre of the Transparent Layer. It will have to be resized. Press CTRL+T. A selection will form around the image.
Step 6 : Keep SHIFT+ALT. You will find corner handles at the corners and the middle. Grab the top left corner handle and drag down keeping SHIFT+ALT pressed. This will resize the image proportionately. Press ENTER to apply the resizing.
Step 7 : Click the Move Tool and drag the second image to the Transparent Layer.
Step 8 : Press SHIFT+ALT and resize. Press ENTER after resizing.
Step 9 : Drag the third image to the Transparent Layer, press SHIFT+ALT to resize. Place it appropriately.
It may be possible that your images may not align perfectly. It should not matter.
Step 10 : There are now four layers in the Layers palette. Layer 1 is the Transparent layer at the bottom. The three others obove it on Layer 2, 3 and 4 are the three images. Click on Layer 2, press SHIFT and click on Layer 4.
All the layers are selected as soon as you click.
Step 11 : Click on the Rectangular Marquee Tool.
Step 12 : Drag out a selection keeping out the portions, like in the middle image, that are sticking out.
Step 13 : Go to Image>Crop.
Step 14 : The images are cropped. Press CTRL+D to deselect.
Step 15 : Go to Image>Auto Blend layers.
Step 16 : The Auto-Blend dialogue box pops up. Panorama is selected by default. click OK.
Photoshop begins blending the three images as soon as you click OK.
The three images have been blended by Photoshop. But it has not done a perfect job. The borders between the images have not been blended perfectly.
Step 17 : The Layers palette looks like this.
Step 18 : Press CTRL+E. All the three layers will merge into one.
Step 19 : Select the Patch Tool.
Step 20 : In the top panel there are two settings -- Source and Destination. Source is set by default. We will be using Source.
Step 21 : Draw a rough selection like this.
Step 22 : Place the cursor in the middle of the cursor and drag (in any direction).
Step 23 : After dragging click the left mouse button once. The selection goes away.
Step 24 : Select another area with the Patch Tool. Draw a selection. Drag the selection.
