One of the key elements that helps blend a CG element into a live action plate is the lighting, and how that lighting interacts with the surface of the model in question. To get an idea of how comlex this can become, take a look at your hand, and see how the light interacts with it. See how there are subtle shadows around creases, tendons and between the fingers. Look at how the light from the computer monitor is reflected off the skin. Think about what would happen if you shine a bright torch against your finger, and how a red glow would shine through.
All these elements need to be replecated in order to produce a realistically lit subject in CG. One solution to these problems is something called image based lighting. Basically, when on location, I took a series of photos of a shiny silver ball from three different angles, then through a series of computer processes, these are unwrapped and stuck together to produce a single image which shows the whole environment.
(Click to see full size image)
(If you look, you can see three images of me taking the photos in the above image.)
Now, this image is then taken into maya and used as an image based light, which is a sphere with this texture on the inside. The image used differs to the above version in that it contains a lot mor information about the brightness in the environment, and it is used to project light of the correct colour and intensity inwards, providing very subtle and realistic lighting. It also gets used to add reflection to the seen, so when used on the dragon, it will reflect the location on the skin and in the eyes.
On the subject of skin, I have kept working on the surface of the skin. I have added an effect called sub-surface scattering, which replecates how light interacts with translucent objects such as skin.
(Click to see full size image)
Now this dragon will probably look quite similar to that in previous posts, with the exception to some changes in the shinyness of the skin. The real difference can been seen when the model is lit with a strong back light.
(Click to seefull size image)
Now you can see the light shining through the thin membrane of the skin, revealing the network of blood vessels within.
This close interaction between the light and the surface is maybe on of the biggest elements that need to be right in order to sell an effect shot like the ones I have planned, so I am hoping that this blends in well when we get further towards our end product.
As a final treat, here is a close up shot of the dragon as it stands at the moment.
As a final treat, here is a close up shot of the dragon as it stands at the moment.
(Click to see full size image)
Until next time,
Alex
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