I had been working on the spiny starfish illustration (Marthasterias glacialis).
The reference pictures I had were mainly from the internet; as despite numerous visits to the underwater area of Seal and Penguin where their tank is situated, I could never time it when the starfish were out in good view... they were always hidden down amongst the rocks in their tank.
So I decided to base the position of the starfish on the image in the top right of the ref pictures.
Despite the starfish hiding from me I knew that their colouring was different to any of the starfish on my ref pictures... there is a lot of variation, but I wanted the illustration to relate to our animals more... so I popped back down after I had drawn the basic shape to get a long look at the animals. Typically one was out in full view... and I didn't have the camera!! So after dashing back to the studio to grab the camera I managed to get a few shots of the starfish before it disappeared back down into the crevices between the rocks.
These would be no good for positioning and the drawing I had done would fit nicely into the box shape available for the illustration on the ID format for fish, so there's no need to change that. But these would be good for details such as the placement and spacing of the nodules on its arms and the colouration.
The illustration itself was done over two days... this is the finished illustration before I corrected the black background to 'pure' black on the computer.
The matt black I paint as the background when scanned in never comes out as 'pure' black so I have to alter this in Photoshop before adding to the ID document. Although this particular fish display does not have a lightbox to display the ID sign I correct the black just in case in the future it is moved to a tank that does have a lightbox. If I did not change the black to '100% black' it would show up greyish on the lightbox and we want the illustration background to join seamlessly with the black of the rest of the ID sign.
To do this I first choose the brush tool and set the size of the brush to a large diameter to cover a large area of the image in one stroke. I then use the magic wand to select the background and then invert this so that when I brush over the image it will only affect the background area. I then choose a bright colour (in this case red) and brush over the illustration until all of the background is covered. Then I change the brush size to a much smaller diameter and change the colour of the brush stroke to 100% black. I then cover the red area in close to the starfish. I get as close as I can but not right up to the edge of the painting.
So the image then looks like the above. Next I change the brush size to an even smaller diameter and zoom right in on the image.
I change the softness of the brush stroke edge from 100% hard to around 50% had so that the colour left by the brush stroke fades out slightly. By doing this I soften the effect on the illustration and it doesn't look 'cut out' of harsh. I take the brush strokes right up to the edge of the painting and in this case it took a long time because of all the fiddly little spines on the bottom of each arm. Until it looks like the pic below all the way around the painting.
I take this opportunity to 'tidy' up any overlaps or bits of the painting that I don't really want there.
The illustration just needs one final 'tweek'... I adjust the colour that was slightly lost in the scanning process.