Reconstruction Tips: Make your own skeletal references!

Alright artists time for...

Today brought to you by your friendly host Craig...

Hi everyone. My tip for today is how to make any skeletal reference work for you.

When trying to construct a scientifically accurate critter it is really important you stick to the proper anatomy of the animal. This means that being (pretty) precise on rough measurements and proportions of your creature are key. The best means to get these right is to use a skeletal reference.

However typically when you find such a reference it isn't quite what you need (if one exists at all!...).

I personally run into problems with pre-existing references as they are often in highly stylized poses, such as this Deinonychus skeletal reconstruction by Gregory Paul. These types of references though having excellently measured proportions and anatomical layout, make it hard for you to acquire useful information about how your animal is put together as the limbs are all folded up and angled in "weird" ways (okay not weird for the living animal [most of the time! sometimes people do impossible things in their skeletals]. However when trying to measure and compare proportions they are less than ideal!).

Further more if your reconstruction is in an unconventional pose, such as my 3D Deinonychus, it is really unlikely you'll find a reference already in your pose. In fact if you do find one odds are really good it is an over done conventional pose anyways!

Meaning if you want to compare your creation directly to a skeletal, you're almost certainly out of luck. Or you'll be forced to copy the preexisting pose. Which I urge you not to do! Too many people keep turning out the same general reconstructions. With an extra 20-30 minutes work you can come up with a reference that can be in any pose you'd like!

So how do you do get this personalized skeletal reference? Why you make it yourself of course!

I'll take you through how I made the reference that I used to cross check my 3D Deinonychus here. Now the pose I'm going for is essentially a dead laid out animal (needed for my 3D posing system), but you can use this procedure for any pose you want!

Okay so the first thing you'll need to do is load your reference into photoshop. I suggest right away saving it as a new file just in case. That way you have the original still at hand should you need it.

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1. Your first real step is carve apart the parts of the skeleton that are at the wrong angle for your purposes.

Some general tips:

Make sure your taking things apart at the joints. You can also take them apart a lot more thoroughly than I have here. Each vertebrae and digit bone can be separated if you want. I haven't gone this far, but you'll note I did separate a few individual neck verts.

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Think about giving each separate bone or limb its own raster layer in photoshop. This makes it easier to manipulate them one at a time, and not risk wrecking your other parts by accident.

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2. With your picture editing software's "Free Rotate" function manipulate your individual bone elements to your desired angles.

Some general tips:

Learn your undo hotkeys for this stage. As it can take some trail and error to get things to look right.

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Have a protractor on hand if your program only allows manipulation by typing. (Some photo editing programs will have nice built in rotation tools that you can with your mouse just twist selections around in your drawing window. Sadly my version of Coreal Paintshop Pro only allows me to rotate things by manually typing in the number of degrees I want it to rotate by. Thus I can not be as precise to start off with unless I have a protractor to look at)

Once you have your piece oriented roughly how you like, lay them out close to their final position to double check. Here is where separate raster layers can be handy, as you can lay them out in their final position, and move them after the fact if you don't like them.

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3. With your parts oriented correctly put them all back together!

General tips:

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Keep a copy of the original picture handy, so that you can make sure you are repositioning all the joints back in exactly the same place.

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If you were using separate layers save a copy of your skeleton in a layer supporting file format. That way you can repose this skeleton again in the future if you ever revisit it!

Okay so once you have your own version of the skeleton you can use it to your hearts delight.

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The way I use it, handy for anyone working in digital medium, is my transparency overlay technique (which you can read all about here), seen here.

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In my case having built my raptor before I had the skeletal reference, I could now see I needed to fix it...

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Just like that my 3D Deinonychus was pretty much spot on (with a few tiny variations, but I'm fine with 90% accuracy... the animals would have all varied individual to individual anyway).

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Outside of my example I'm hoping you can see applications for this technique in your own work!

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On the last topic of what if there is no pre-made skeletal reference for your current animal project?

Well if you have a half descent photo of the actual fossils, my technique works just fine on them too!!!

So good luck in the future with your own skeletal references!

Making a Prehistoric Flood

By Craig

So the first thing I do when sitting down to do a composition is think to myself what is the story I want to tell today.

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When I approached my first piece for the Ceratopsian Gallery, I had the idea of showing the moment that one of the great Ceratopsian fossils sites was created. The particular site I had in mind was in northern Alberta at a place called Pipestone Creek, where a massive bonebed containing the remains of hundreds of Pachyrhinosaurs were discovered in 1972 (and worked until quite recently). These animals had all clearly been killed by a flood, and as it was pretty much just them in the bonebed they probably were all alive together before being killed (aka a herd).

So the story I wanted to show was one of the herd encountering this natural obstacle. Though it would claim the lives of some who tried to cross it, others would make it across successfully.

Here is the final picture for reference.

The only way I could pull off recreating a flood in the timeframe I had at the time (having to set up ART Evolved along side making this piece) was to create it via a photo composite.*

For those of you who have never heard the term composite before, this means taking a photograph and adding and/or subtracting things from it. In this case I was going to not only being adding Dinosaurs, but also a flooding river.

Looking through my many lovely pictures of the New Zealand landscape (it is such a great place to sub in for a Mesozoic era Earth) I discovered this perfect riverbank.

There was only one problem. There was no river, that alone one in flood!

However in my photo arsenal I DID have pictures of the local aqua duct flooding from 07.

It was not ideal at all though. The scale was wrong, it was too close up a shot. Not to mention the angle was all wrong.*

Still beggars can't be choosers so...

After some realigning in Paint Shop (my cheap Corel knockoff of Photoshop) I was able to get the flood facing roughly the right direction. Then some creative cutting and pasting supplemented by cropping of the water in a separate layer from the riverbank I had a rough flooding river.

Now sadly I didn't save this initial phase (I wasn't thinking about making a "Making of" post at the time) so you'll have to take my word on what it looked like. The problem it suffered from (more so than this finished one) was that the river unrealistically covered up the trees at the bottom of the hill.

So I went in and cut and paste several of these (but not all) back on top (in the photoshop layer sense) of the water. It was still missing something. So I went and grabbed some random tree tops and added them out further into the water to add some small growth submerged. That looked better, but one thing was missing. So some cut and pasted random splashes from the flood photo were added as water spray along the leading plants.

Though not perfect, this flood wasn't too bad considering the elements I had to work with.

Next it was time to add the Dinosaurs.

Recently I went through a huge Centrosaurid construction binge on Carrara, my 3D program, in anticipation of a big event I'm doing over on The Tyrannosaur Chronicles (check for it in about 2-3 weeks). So I had several short frilled Ceratopsians to choose from, including the two best known from mass bonebeds related to floods. Centrosaurus proper and Pachyrhinosaurus. I choose Pachyrhinosaurus as it is among my top favourite dinos and there have already been tons of pictures of Centrosaurus in floods.

Admittedly I am not totally pleased with the baseline colouring I gave this Pachyrhino, but I did figure that out till I was headlong into putting the model into my flood!

So having a 3D Dinosaur model is only a part of the battle. Next came the long process of duplicating multiple animals from the original, tweaking and individualizing them, posing them, and finally repositioning these in relation to the picture.

This was a whole day endeavour. Some of my effort is obvious, and is easily seen. Such as my remodeling a young "monoclonius" version of a Pachyrhino (which looked like identical to other juvenile Centrosaurids when their young).

Some of my tweaks were not so clear. For example if you pay close attention to each animal they're all slightly different lengths and sizes, and their horns are differently sized and arranged. I think this isn't obvious as every animal is identical in colouring, as I didn't have time to make new shaders for each animal. I think if I had made slight changes to each of their colouration these horn and size differences would have been emphasised rather than hidden.

Regardless, here was the poses and positions I ended up with. However without more work the picture was far from realistic looking so far. Dinosaurs that were underwater were still completely visible. None of them were casting any shadows either, which is a key element for compositing to look real!

So next I constructed a "shadow catcher" set for the photo. A shadow catcher is pretty much what it's name implies, it is an object in my 3D program that "catches" the calculated shadows of objects I'm rendering as per the lighting settings in the scene. At the same time they don't block or cover up the background, merely project a shadow onto it. You can see my shadowcatcher objects in the 3D window screen shot I included before, they are the grey rectangles the Pachyrhinos are standing on or swimming through.

Though this may sound and look easy, but it was actually quite time consuming. You aren't building the set from scratch. Rather you're having to recreate and mimic the angles and placement of preset positions determined by the background photo, or as they call it in the biz the "plate".

With my shadowcatchers in place I was nearly there. However the Dinosaurs were lacking excitement and interaction with the water, and the herd up on top of the hill was floating above trees that were clearly supposed to be in front of them. (Shadowcatchers are insanely time consuming to build for trees and other none straight objects).

So I went in and photoshopped the forest back in front of the waiting Pachyrhinos, and added splashes around the swimming ones.

Giving me this as my end product.

It's not perfect, but it could have been a lot worse too.

My main regret is the lack of animals. I'd have like 3-5 times as many. Maybe when I have more time (yeah right! there's a dream commodity) I'll retry.

So the new story is the back or front end of the herd arrives at the river where the banks are too steep to descend safely, minus one gentle slope. The majority of the animals take this single safe path to the water. However on the sides we see inexperienced youngsters risking the steep hills with varying degrees of success.

I hope this "making of" has been useful to you.