Deke’s Techniques 045: Creating a Synthetic Rainbow

This week, I show you how to make a synthetic rainbow, one that actually looks like an actual one, in Photoshop. If I were a silly little girl, I might posit the rainbow in back of a magical prancing unicorn. But I’m a silly little boy, so I set it in back of a highly aggressive, man-eating shark.

“Pardon?” I here you say. “How do you put a rainbow in back of a shark??” Watch the video and find out.

In the meantime, here’s the official description from

November chilliness got you feeling cold and gray? In this week’s free movie, Deke shows you how to brighten your world with your very own realistic rainbow, constructed completely from scratch in Photoshop. Start with a simple rectangular marquee, add a custom gradient, bend it into an arch with the Transform command’s Warp feature, and fine-tune the with a little blur and surprising blend setting. The result, is this promise of gold you see here: 

A synthetic rainbow created entirely in Photoshop

Deke originally came up with this technique as an addition to a “skyshark” project he created for his new Photoshop Masking and Compositing: Fundamentals course, where in Chapter 6 he shows you how to use the Color Range command to isolate a threatening shark and transport it to an unsuspecting meadow. Of course, not everyone sees a picture of a ferocious carnivore in an implausible environment and thinks, “What this image needs is a rainbow,” but I’d imagine you can think of a project where having the ability to create a suitable rainbow (or double rainbow) at will might be just the trick.

And for members, Deke’s got a follow up video in the Online Training Library this week in which he shows you how to create a realistic shadow in the grass underneath the floating shark. That is, if you call a shadow cast on grass by a floating shark with a rainbow in the background “realistic.” But creating photorealistic (if not outright reality-based) shadows is a useful skill for your less fanciful work as well. So suspend your disbelief and check out this useful technique.

Join us here next week for more Deke’s Techniques!

Don’t get all literal on me. Of course, the shark needs a shadow. Go to my Deke’s Techniques stream at to learn more.

Next entry:dekeSpeak November 8

Previous entry:“Photoshop Masking & Compositing: Fundamentals” Goes Live Today


  • Awesome - that’s a beautiful

    Awesome - that’s a beautiful rainbow!

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