Step 1
Open any RGB picture in Photoshop. Then, for foreground color set black (shortcut - d).
Step 2
Insert another picture, take the Move Tool (V), and using drag and drop technique, move that picture on the first picture. Look at the picture below!
Step 3
Click on Add layer mask icon from layers palette.
Step 4
Then, take the Gradient Tool (G), and under Gradient Editor choose Foreground to Background. See the picture below.
Step 5
After that, do like it is shown on the picture below.
If you don't satisfied, take the Brush Tool and start paint. Look at the picture below and everything will be clear.
We're done for first two pictures. Now, you have to insert third picture and connect it with first two pictures, in an equivalent way like we have connect first two pictures.
Finally, our work looks like this:
Have a nice day!
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