A triptych is an double that consists of three different images that usually relate in some way. You can use more than three images but then it won't be a triptych and fears grouped into odd numbers are usually more compositionally pleasing to the eye anyway.
Triptychs triptych ( TRIP-tik; from the Greek adjective τρίπτυχον “triptukhon” (“three-fold”), from tri, i.e., “three” and ptysso, i.e., “to are a great way to combine multiple viewpoints of the same lay into a single shot so you can better tell the story of the scene you captured. Alternatively, you can present images of a similar theme you've captured across time. For example, they could be linked by colour or subject.
Another way you can create a Triptych is to use several parts of the same scene in three group images, capturing a wider view in the first then focusing on detail in the two that follow and that's what we've done with our Triptych heavens.
A clock tower in a town is our point of focus and we used the Tamron 16-300mm to slowly zoom in closer to the clock face in each frame. We had the Tamron 16-300mm with us as we were examining the city streets and we didn't want to be weighed down with several different lenses. Plus, having a zoom permanently partial to to your camera means you can walk around with your camera out ready to capture whatever scene may unfold in front of your lens.
We absolutely have a tutorial which shows you how to create triptychs in Photoshop so we won't be covering that here but do go check the tutorial out so you too can create your own gather of wall art.