To me, Pixologics Zbrush lives in a world somewhere between 2D and
3D never really knowing which camp to lie in. With it I can create
3D meshes that can be textured and have native materials added to
them. Zbrush uses a technology called `Pixols` that sees each pixel
as a 3D image that retains width, height and, more importantly, depth
information. Once you `snapshot` a model (or Ztool) into an image
you can still add depth with a number of brushes, change the model's
material and even adjust the lighting. In this tutorial I will attempt
to walk you through the creation of a detailed head study (called
`EFXterminator`). The steps will lead you through modelling the head
from a basic 3D sphere, adding colour and material to the model then
creating and adding textured eyeballs. Finally, we'll model the hoses
and metal parts of the image before moving on to lighting and rendering.
The steps I describe are not the only way to achieve things in Zbrush.
It is such a versatile program that you can find a multitude of ways
to do the same job. I used Zbrush 1.2 to create this image with a
document sized at 2500x2500 with three layers. It is possible to re-create
this image using the demo version. However, some of the settings and
sizes may vary. I use a 1 gig AMD-based PC with 512mb of RAM and Win98.
To start off this modelling session you need to understand a little
bit about the TRANSFORM panel. (See figure 1.) The following steps
apply to any 3D object or primitive that you can select from the
TOOL panel. To model an object you need to place it into the document
window. To do this, with the tool (model) selected, click into the
window and drag out an object. To move, scale or rotate the object
you can use the panel or press key `W`, `E` or `R` respectively.
When pressing any of these keys a multi coloured `gyroscope` appears.
Try each of the modes to get used to using the gyro to get the desired
TIP: To `move` along an axis, pull the coloured
end of the gyro. To `scale`, click inside the gyro and drag up or
down. To rotate, click inside the gyro and drag in the desired direction
To model or shape the object into the desired shape you need to
enter the EDIT mode, press `T or use the transform panel (Figure
1.) When in the EDIT mode the cursor turns to a red dot with a ring
surrounding it. The red dot is where your changes will be made on
the object as you model. To rotate the model in this mode click
while holding the cursor away from the object and drag up or down.
Different effects can be achieved using the transform panel by clicking
`draw pointer` (add depth to the object or remove it by holding
down ALT), `move` (pull or push an area of the object) and `scale`
(increase or decrease in size an area or polygons). (See figure
3.) To enlarge the `area of effect` on the object go to the DRAW
panel and adjust the `DRAW SIZE` slider up or down. You will notice
that the red ring grows or shrinks helping you to judge the size.
In the DRAW panel you will also find `RBG Intensity` and `Z Intensity`
which affect the amount of colour and depth applied to the object
as you model. At some stage you may need to turn `colour` or `Z`
(depth) off. This is done by selecting or deselecting the correct
box (green is selected, grey isn't). These steps are the basics
of constructing any 3D organic model in Zbrush.
TIP: The best results are achieved by keeping
the `Z Intensity low when adding depth or pulling a portion of the
model. This will let you subtly adjust the shape stage by stage
using the different tools.
Now is a good time to tell you about `snapshotting`. A model (Or
ZTOOL) in Zbrush is `live and editable` in the document window until
you `snapshot it into the image (Press CTRL+S or the `camera` Icon
shown in the transform panel in Figure 1.). Once you `snapshot`
a copy it is no longer editable and cannot be moved or rotated.
It does, however retain its depth information and can be modified
with some of the 2D tools (Simple Brush, Blur Brush etc.) The original
ZTOOL remains in the TOOL panel and can be saved as a .ZTL (Native
format) or exported as an .OBJ or a .DXF Losing the facility to
modify 3D objects was one of the first hurdles I came across in
Zbrush. It is such a departure from the norm that it takes a while
to feel comfortable with it, when you do, it becomes second nature
and going back to being able to rotate a wireframe whenever you
like seems weird.
MODELLING THE HEAD
Zbrush. Go to the DOCUMENT>MODIFIERS panel (usually on the left)
and adjust the document size to Height 2500, Width 2500 (if
you have the demo you will be limited to 640x480). Select `PRO`
to allow you to adjust the proportions. To begin modelling go
to the TOOL panel and select the Sphere3D tool. Click TOOLS>MODIFIERS>INITIALIZE
and change `Hdivide` to 512 and `Vdivide` to 256. This will
give us the maximum possible subdivision count for this object
(lots of polygons).
Go to the DOCUMENT>MODIFIERS panel (usually on the left) and adjust
the document size to Height 2500, Width 2500 (if you have the demo
you will be limited to 640x480). Select `PRO` to allow you to adjust
the proportions. To begin modelling go to the TOOL panel and select
the Sphere3D tool. Click TOOLS>MODIFIERS>INITIALIZE and change `Hdivide`
to 512 and `Vdivide` to 256. This will give us the maximum possible
subdivision count for this object (lots of polygons). Click in the
document window and drag out a sphere leaving plenty of space around
it. As we are only modelling the head at this stage the position
doesn't actually matter. At this stage we want to go straight into
`EDIT` mode so press `T` on the keyboard and a red dot/ring will
appear. Because the head we will be modelling is fairly symmetrical
we need to turn on `symmetry`.
Go to TOOL>MODIFIERS>DEFORMATIONS>SYMMETRY and select `X`. You will
now have two dots on the model. Any change made to one side of the
model is exactly duplicated on the other side saving you a lot of
work. Figure 2. To begin the modelling you will need to `pull` the
Sphere into the basic head shape. Select `Move` (W) and pull the
bottom of the sphere down. If the effect is too dramatic you can
CTRL+`Z` to undo. This is a good time to adjust the `DRAW` size
to get the right effect for this part of the modelling. Click-Hold
away from the head and rotate it slightly. Pull out a neck, back
of head, chin and a forehead. (See figure 2. Heads 1 and 2) To add
features to this cone-head we need to switch to the `DRAW PONTER`
(`Q`). Rotate the head so that it faces you and `paint` depth onto
the face. Build up the forehead, the nose, cheeks, lips and ear
bumps. Add a bump for each eye for now. To indent the model, still
in the same mode, hold down ALT and paint. Indent the cheek recesses,
nostrils and the eyeholes. Remember, you may need to reduce the
`Z Intensity` in the DRAW panel to make subtle adjustments. Try
to follow the steps in Figure 2. Keep rotating and adjusting until
you get the desired effect. (See figure 2. Heads 3-8). Add features
like frown wrinkles and bags under the eyes. If you need to move
the head on the canvas you can exit `EDIT` mode by pressing `T`
again. The gyro appears and you can select `MOVE` by pressing `W`.
Pull the gyro (grab the coloured ends) and move it in the direction
you want. To continue modelling, press `T` and re-enter `EDIT` mode.
To model the ears you can use `SCALE` (E) to enlarge the ear area.
Use `DRAW POINTER` to shape the lobe and make an indentation then
use `SCALE` (E) to reduce the ear back down to the correct size.
This will take some practice as it is not easy the first few times
you try it. Make sure you model the `bumps` in the head where the
metal hoses will fit.
NOTE: If you select another tool by mistake at this point you will
`snapshot` your head into the document - common frustrating mistake.
If this happens CTRL+`N` clears the entire layer and you will notice
a copy of your head is left in the `TOOL` panel. You can re-select
it and `draw` it back into the document and continue to edit it.
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Author:admin Submitted: 2006-03-31 17:19:58 UTC Tags: Software: Zbrush Views: 199,594