Multiplicity photography is a technique in which same person appears in a photography multiple times. Creating a multiplicity photo is surprisingly simple and also a great way for beginners to learn how to use layer masks effectively. This trick is also known as Sequence Photography. It’s really easy to do, trust me.
The first step is to click the photos that you will need in the final multiplicity image. Click a series of photos with the subject in different locations, performing different poses etc. Get creative with the posing like jumping in the air, pretending to look at themselves etc. Try to position the subject so that each pose is not overlapping another pose.
Set your camera in full manual mode to ensure that you’ll get consistent exposures throughout the shots, which will help the final image appear seamless. To avoid blending problems later, shoot photos quickly so that lighting conditions don’t change. Lighting shouldn’t differ between shots. Set up focal length, aperture, shutter speed and other settings beforehand and don’t change them in between shots.
Use tripod to keep your camera fixed while shooting the subject moving into different postures. It avoids camera shake and will keep your images aligned. You can also use a wireless remote or self-timer.
Open an image editing software like Photoshop or GIMP, which supports layers. Open your non-overlapping images and use layer masking to create the multiplicity effect as shown in below tutorial. Stack your photos on top of each other and then mask off the entire layer. As next step, bring back (by unmasking) just the part of the photo that has your subject in it, leaving the rest of the layer masked out.