Theory Lesson: Presenting your models

Hi guys, recently I posted a render of a speed model of mine: http://alextelford.carbonmade.com/projects/4613637#1 and a few people asked me what materials, lighting and compositing techniques I used, so here is a nice long theory lesson on not only how I created the effect, but also what each component actually means so you can use these techniques on your own project.

You can download the model from http://www.facebook.com/unitycookie/ (You may have to scroll down a little if your visiting after the 2nd January 2013).
And you can get the photoshop file for this render here: http://bit.ly/W0GiOT

Don’t like long videos?
You can jump to each section in the video using the timecode at the contents section.

There is also a shorter text/image overview beneath this video.

Ok so first, let’s start with the final result:
ldu

Fairly simple to achieve, but where should we start?
Let’s start with a brief rundown of the process involved:

1_contents

We start off by preparing our 3D scene with a bit of careful placement, then we move on to materials, lighting and rendering before doing a bit of post production work.
I like to break my post production down into the Base, color grading, grunge overlays and lens effects.

Let’s take a look at how the scene is put together:

2_scene

Ok so fairly straightforward, we place our camera so that it is looking at our object at a three quarter angle, and looking slightly upwards to make the Mech feel more powerful. Looking down is good for weaker models such as a scared child.
Next we duplicate our Mech and rotate 180 degrees so we can see both sides of our model and showcase all our hard work.
We set the camera focal length here for a depth pass to be used for fog and masking, not depth of field as we don’t want to blur details for model showcasing.

Moving on we can look at materials, lighting and rendering:

3_setup

Fairly simple here as we aren’t all master lighters or shader writers.
Materials:
Plain slightly glossy shader, 50% grey, we only want luminosity values out of the render and glossy reflections will add to the appeal, just keep it subtle and not super reflective, closer to lambert than phong is better.
Lighting:
Physical sun and sky, that’s a standard skylight as we don’t care much for fancy lighting here.
Rendering:
Render out a depth pass, beauty pass, occlussion pass, and an object index pass for a mask of your model so you can easily mask it from the background in comp.

For blender users you will need to get those passes out of blender and into something photoshop can handle:

4_rendering

So it’s looking horribly blue at this point but don’t worry, we will deal with that soon.
Use a map value to get the z-depth pass (use a very small size value to get a good range) and an id mask node to get the mask for the model.

Time to get compositing!
Let’s start with the Base:

5_base

The base is very straightforward, paint out any errors from the render such as flipped normals, and add any extra occlusion.
In my case I have also desaturated the image so I can work from a flat base.

Next let’s move on to the grade:

6_gradeGamma

 

Because Blender defaults to linear workflow we must gamma correct our render, in my case I am using a gamma of 1.6 though 2.2 is your value if you are using maya or max.

Let’s add some color to our image:

7_gradeNoiseRamp

 

I do like my color ramps in grading almost as much as I love vignettes, setting the gradient ramp to noise let’s us get an uneven flicker of color across our image, orange and teal is another popular color ramp.
So why is my blending so soft?

8_gradeBlendIfs

Bring on the blend ifs!
by using blend ifs we can define what luminance range we want to blend from and to.
Holding Alt and clicking on one of these slider points let’s you split them up to get a smoother blend.

Our background is a little bright so let’s deal with that next:

9_backgroudTintBorder

Simple one here, a hue and saturation set to a dark desaturated blue on colorize, using the mechs ID mask as a mask.
Also I increased the selection size by 1 so the adjustment layer will overlay by one pixel giving it a slight border effect, you can also have a separate adjustment layer just for the border by making a selection from the ID mask, and modifying the selection to a 1 pixel border for a stronger effect.

Almost there, but let’s add some grunge:

11_grunge

We use some grunge overlays that can be easily found online over at cg textures (concrete makes great grunge maps) and using blendIFs and multiply/soft light we can blend them over for a subtle dirty camera look.

finally let’s finish with some lens correction:

12_vignette

For this image I chose to stick to a subtle vignette to draw in the viewers attention, but you can also add in some subtle 0.5 lens distortion, or 5-10 chromatic abberhation if you want to.

So that concludes this theory lesson, if you have any questions let me know.

You can download the model from http://www.facebook.com/unitycookie/ (You may have to scroll down a little if your visiting after the 2nd January 2013).
And you can get the photoshop file for this render here: http://bit.ly/W0GiOT

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  • Demoniq

    I must admit that this render looks VERY appealing to the eye. I really have to try it out on my “warhammer 40k Drednought” model :D

    Thanks for the in-depth explanation. regards

  • mohamed

    wow!!
    Idon’t seen good tutorials like your tutorial
    good!thank you