Adding a rainbow to your images can be done in many different ways. However, not every technique is easily put into practice or can offer a remarkably consistent result. For example, the prism method is very efficient to get the effect on your files straight out of camera, but it can make focusing and composition a bit difficult. In this tutorial, Jessica Kobeissi will show you a couple of simple techniques using only Photoshop.
While some people will argue it’s always best to get your creative vision in camera, with digital, it’s sometimes easier to get it right in postproduction. I’m all about making the most out of a situation to get everything right in camera, but honestly, when efficiency is essential, Photoshop is sometimes the better choice.
In the video above, Kobeissi demonstrates how she adds a rainbow light effect, similar to what you could get by shooting through a prism or making light shine through a piece of crystal. She will show you multiple ways to achieve your desired result, either with pictures of a rainbow you took, by drawing it yourself, or by adding a gradient map on top of your image. Of course, you’ll have to play with blending modes to get the perfect look, but different ones can work. So be sure to watch the full video to learn all about both the techniques and blending modes that work best together.
Now that you know how to do this, please never do this.