My most important tip is to sit down and gather some references of tropical fish. Many of the tropical fish that we know of live on the world's coral reefs, so Googling "The Great Barrier Reef", for example, should be sufficient to get you started on gathering inspirational material.
You'll notice from the photos that many tropical fish are, of course, colourful. My second tip is therefore to have your fish swimming in fairly bright, happy colours.
Tropical fish often feature diverse patterns across their bodies, which you can use as inspiration to create some cool fantasy patterns of your own.
In addition, keep in mind the often flat, leaf-shaped bodies of the fish. Using that shape in your design would make the fish look like they belong in more tropical waters.
My third and final tip for you is not to make your fish design overly complicated. To make something fantasy doesn't mean you have to go insane with the design and create something so abstract no one but you understands it.
It's always a good idea to base your fantasy design in reality – especially with animals – and then throw in a mix of elements that your viewer might not have expected to see. As an example, why not give your fish wings?
Or a unicorn horn? Or make it a fairy fish? Or just about anything else that tickles your imagination. Digital painting enables you to try out all these possibilities, and more!
01. Thumbnail biters
Start scribbling! I simply go a little crazy and do random strokes and shapes with a wispy brush on a separate layer in Photoshop.
This is just to let the imagination flow to see what comes out and what happy accidents I can bring on.
Don't worry about anatomy just yet – instead, relax and have fun. These are only the first scribbles, after all.
02. Reeling them in
I pick out my favourite scribbles, lower the Opacity to 20 per cent, create a new layer on top of the scribbles and start sketching.
I add more detail, while also taking out anything that doesn't make sense to me.
Now is also a good time to start thinking about perspective and anatomy and whether the shapes work well together or not.
03. Chips with that
I lower the Opacity of the sketch layer and, on a new layer below, add saturated colours with a Soft brush for a smooth transition between the different hues in the fish's scales.
After establishing the base colours, I merge the sketch and colour layers and then begin rendering with a simple oval brush and a select few textured brushes.
04. Zoom zoom
Avoid zooming in too much in the early stages of colouring in Photoshop. Zoom in and you risk losing sight of the big picture.
Zoomed out, it's much easier to see whether the colours work well together or not.
Originally a freelance illustrator from Sweden, Viktoria now lives in England, where she works as a concept artist for Atomhawk. This article originally appeared in ImagineFX (opens in new tab) magazine issue 107.
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