Sunday 20 March 2016

The Rocky Transition From Paint To Pixels

Orca flies the flag


Last March, noted zoologist and living-encyclopaedia-on-tetrapods-and-selected-fish, Darren Naish, sent me some outlines to colour for Tetrapod Zoology's April Fools article. Cetacean Heresies detailed the bright colouration of extant cetaceans, and how those colours go undetected by the pitifully inadequate human eye. That black-and-white orca in your ornamental pond? Fringewhiner's Chromatic Truthometer shows it for what it really is: a gay rights poster boy. It's rainbows all the way. Rainbows are good.

Peponocephala and killer whale pod. (By Darren Naish and Gareth Monger; CC-NC-SA 2.0)

Special offers on piss-taking


The article was good fun, and was a veritable 2-for-1 deal; it parodied both a well-known fringe science blog, and one of those inexplicably popular (and subsequently internationally famous) internet memes - a photo of a blue-and-black dress which appeared to some internet users as a white-and-gold dress. In one of those bizarre twists, the woman who originally photographed the dress then came into the printshop where I work to run off a few copies of the photo, and STILL wasn't sick of talking about it.

Skamps (I think that's what we called these at uni) of generalised mosasaurs in different poses and angles. Pencil on paper. (Copyright © 2016 Gareth Monger.)


So why am I milking whales, ten months on? In short, it was the first time I'd used a digital package to put together a full-colour illustration, albeit in a rather rushed manner. At the time, nearly all of my work was coloured by hand, using gouache. (If you're not sure what that is, read my article on gouache at ArtDiscount.) If you are an experienced gouache user, you'll know it's no slower a medium to paint with than anything else, the main limitation to speed being how much detail you want to put into your image. It's considerably quicker to work with than oils, it dries reasonably quickly, and can be forgiving. However, there's a basic set-up time associated with it, namely the time taken to stretch paper, which can, if you're lucky, be as short as a couple of hours. There's nothing better than seeing a perfectly stretched sheet of 140lb Arches watercolour paper, ready to receive its first pencil mark. Conversely, there's nothing worse than seeing that your adhesive tape has failed on one side of your paper, and you've got to redo the whole damn thing. (For hints on paper stretching, see my dA post, here.)


Preliminary sketch (top) of a pair of Platecarpus, with soft tissue outline based on Lindgren et at, 2010. Revised outline (bottom) tweaked to reflect social media comments by palaeontologist Nathan Van Vranken. Note the shorter intermediate caudals' section. Pencil on paper. (Copyright © 2016 Gareth Monger.)


Material costs


This time, however, I heeded advice regarding digital illustration, and figured that these kinds of non-commercial, tight-deadline jobs would benefit from employing a more-speedy process. Material costs are also a consideration, and when a single sheet of paper costs upwards of five pounds, digital art offers a cost-effective alternative. That's not to say I've fallen out of love with toxic pigments and plant-based substrates, it's just that digital painting is very, very convenient. Also, I may go a couple of months without breaking out my paints and, inevitably, they dry out. Yes, they're water-based, but they're also awkward to rehydrate whilst in the tubes. The easiest way to get any use out of dried gouache is to slit open the metal tube and use it in the same way you would a watercolour pan. Of course, you're not really using it as gouache, but it eases the pain of seeing expensive paint dry out.

Pencil outline after some clean-up, and an initial pass through Photoshop to add some body-forming shading. Pencil on paper/digital. (Copyright © 2016 Gareth Monger.)


Going Digital, Sorta...


And so, with last year's April 1st in mind, and probably also inspired by seeing Amin something-or-other's passive-aggressive, and generally unwarranted, comments about Nic Grabow's (I think) deviatART mosasaur, I decided to knock out a quick full-colour render of a mosasaur, complete with background. Google's luck-of-the-draw-type results would determine the genus, which ended up being Platecarpus. Back in 2010, Johan Lindgren, Michael W. Caldwell, Takuya Konishi and Luis M. Chiappe published in PLOS ONE a paper on convergent evolution in aquatic tetrapods, focussing on a specimen of Platecarpus which displayed some excellent soft tissue preservation, and which suggested that a crescent-shaped caudal fin was present in life.

 Lindgren, et al (2010). CC-BY-2.5




A reconstruction in Lindgren et al (2010) (left) suggested a possible soft tissue outline for Platecarpus, based on the specimen discussed in the paper. The dorsal portion of the fluke is only tentatively restored, as implied by the fuzzy margins, but it's enough to offer a hint on how to progress with an illustration for a palaeoartist. Scott Hartman also writes about this at Skeletal Drawing, in the article 'Mosasaur Tails - Teaching the Controversy', and offers a handful of likely shapes which a palaeoartist may wish to adopt. Whatever the case, the traditional view of mosasaurs as having essentially lizard-like tails, albeit laterally compressed and ribbon-like, is out of vogue, especially for later genera, and shows that a more (superficially) traditionally-fish-like fluke was adopted by secondarily aquatic reptiles in several disparate groups. Oh, and dorsal frills are out too, having been mercilessly copied from Charles Knight's Tylosaurus for decades. Hey, I did it (over a decade ago, mind).


A pair of Platecarpus, lured into posing for this image by the promise of a David Attenborough voice-over. Digital. (Copyright © 2016 Gareth Monger.)

So here's my full-colour illustration of two Platecarpus, swimming around calmly like obedient Seaworld killer whales. The original layout was an evening's work; the colour work took a second evening. On the whole, I'm pretty pleased, and yes, of course, there are things I would change/add. Integumentary structures, for example, aren't evident, but then they might not be at this distance. The foreshortening on the caudal fin caused some confusion, with some commenting that the fluke angles were incorrect. They weren't, or, at least, they were based on the aforementioned reference, and it was the foreshortening causing them to appear unfamiliar. But that's to be expected when most pictorial reference is in diagrammatic, lateral view. One noted mosasaur expert didn't like the blubbery look; another palaeontologist figured it simply denoted healthy individuals. There was a speculative angle to this, which was to show a more fluid outline in an animal which spends its entire life in fluid.

But on the whole, not so bad for a couple of evenings' work.

References:

Hartman, S (2016) Mosasaur Tails - "Teaching the Controversy" www.skeletaldrawing.com/home/mosasaurs-teaching-the-controversy

Lindgren J, Caldwell MW, Konishi T, Chiappe LM (2010) Convergent Evolution in Aquatic Tetrapods: Insights from an Exceptional Fossil Mosasaur. PLoS ONE 5(8): e11998. doi:10.1371/journal.pone.0011998

Naish, D (2015) Cetacean Heresies: How The Chromatic Truthometer Busts The Monochromatic Paradigm. http://blogs.scientificamerican.com/tetrapod-zoology/cetacean-heresies-how-the-chromatic-truthometer-busts-the-monochromatic-paradigm/


Want to support me?


If you like what you're reading and you want to help me keep this going, maybe take a look at my Redbubble page? Here's a mostly-relevant mosasaur (Globidens, not Platecarpus, but who cares?):


Globidens, Haida-style, available on t-shirts, mugs, and a butt-load of other stuff, via Redbubble.