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Lighting and Cameras
When you create a scene in Blender, you start with a few basic elements that will include
a camera, but may or may not include a light. Remember that what the camera sees is
what will render out as a picture or movie depending on what you tell the program you
want as a final output. To get a simple rendered view, press the “F12” key. This will open a
window that will display the rendered output of what the camera is focused on. If the picture
is black, you do not have a lamp or the lamp settings or placement in incorrect. To exit the
render window, press the “
Esc
” key.
Lighting
In most cases, you will need more than one lamp in order to properly illuminate your scene.
Most scenes usually require 3-4 lamps.
Be careful not to use too many lamps!
The different
types of lamps available for you to use are as follows:
Lamp-
Basic Blender Lamp- shines all directions
Area-
New lamp type- provides large area lighting (like a classroom)
Spot-
Shines a direct angle of light
Sun-
Provides an even angle of light, regardless of placement from objects.
Hemi-
A wider light, much like area lights.
In traditional Blender rendering, only spotlights are able to cast shadows. However, with
the introduction of Raytracing (discussed in a later chapter) all lamps can cast shadows.
Lamp Settings:
To create a lamp, position the 3D cursor in a desired location and press the “
Space Bar
”
and select
Lamp.
The lamp will be placed on the screen. You now have several options to
select. With the lamp selected, click the
Shader
button and
Lamp
button
to
bring up the adjusting options. Here’s what you see:
Lamp Types-choose the style
Distance and Energy Setting- how bright and
how far the lamp shines
Lamp Color
Lamp Name
Shadow and Spotlight Settings
There are other lamp setting available, but for now, these are the basics.
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Spotlight Settings:
Spotlights are unique in that you can simulate a foggy scene with them and cast shadows
in the traditional Blender program. Raytracing (discussd in a later chapter) can cast
shadows for all lamp types, but because of the more complex rendering calculations that
need to be performed, renders much slower. If you watch professionally made animations
on T.V., you will see that raytracing with reflections is not always used because of the
rendering time. It is only used when needed. You can do the same thing. Here are your
spotlight settings:
Spotlight Si and Bl- sets the spotlight
beam angle and edge softness
Select Buffer Shadow-
traditional, faster
spotlight settings
Lamp Color, Distance,
Clip Start and End- These
need to be set to just include
the objects that need to cast
shadows. If clip start is too far
above the objects or if clip end
it too far away, shadows won’t
work.
and Energy as before
Buffer Size-higher
numbers mean
smoother shadows
Halo and Halo
Intensity- gives
and controls a
smokey effect
In order for the shadows to display in your render window
(
F12
), you need to tell the program to render shadows if
it isn’t set to do so already. Click on the
Scene
and
Render
buttons found in the bottom
and find
the
Shadows
button:
Experiment with the different types of lights you have available. Different lights can be
used to get different effects. As mentioned before, try not to add too many lights to your
scene. It is better to keep it down to 3-4 and play with their locations and setting, rather
than flood the scene in light. Think of it in terms of real lighting situations.
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Cameras:
By default, your scene already has one camera and that is usually all you need, but on
occasion you may wish to add more cameras. You add more cameras by hitting the
Space
Bar,
like creating all other objects discussed up until now.
To change which camera is
active, you need to select that camera and press “Ctrl” and number pad “0”.
This changes
the active camera.
Like all other objects in Blender, you can adjust the camera settings as well. With the
camera selected, click on the edit button.
Here are some of the settings options
you have:
Lens-
Set-up a lens length much like a real camera. 35mm is a good, safe
setting, but wide and tight angle setting work for different needs.
Clip Start-
How close an object can get to the camera and still be seen.
Clip End-
How far away objects can be seen by the camera. In very large
scenes, this needs to be set higher or things “disappear” from view.
Draw Size- How big to draw the camera on the screen.
Ortho-
Used to set the camera from showing a true-life perspective view to
an orthographic view.
Show Mist/- Used to give you a visual display of how far the camera sees.
Limits-
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Lighting and Camera Practice Exercise
Open your
Sculpture
file and add lighting and set the camera for a nicely rendered view.
Create 3-4 lights for your scene and feel free to experiment with different types of lamps.
Use at least one spotlight and enable shadows in the render settings (see page 25 for
details). Practice placing lamps for good illumination on all sides. The example below
could be used as a model.
Spotlight
Lamps
Lamp
Lamp
Spotlight
Lamp
Top View
The “F12” Rendered View
** Call the instructor when finished**
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Importing Objects
One of Blender’s strong points is the program’s ability to accept several generic types of
3D files from other programs. The most popular used are:
VRML (.wrl)
files- Many programs are able to export their files as
VRMLs. SolidWorks is a good example that we use.
These files import into Blender without any problems
in most cases.
.DXF
files-
A very popular file format for exporting and sharing.
AutoCAD and SoftPlan architectural software
traditionally exports with .dxf formats. Again, Blender
usually accepts these files flawlessly.
To save a file as one of these types from another program, you will need to find an
export
command or a “
save as
” option. This will vary dependig on the program you are using.
Refer to that programs help files. To import a VRML or DXF file into a Blender scene,
open a new drawing or one you wish to insert the object(s) into. Blender does not have an
import command, you just use the
Open
command in the
File
pull-down menu. The program
knows that you are trying to open something other than a .blend file and will insert it into
your current scene. Now you need to find the object(s) you just inserted. Depending on
how that object was drawn, it may need to be resized or rotated.
Appending Other Blender (.blend) Files:
If you wish to insert elements from one Blender file into another one, you need to use the
Append
command in the file pull-down menu. The append command was discussed on
page 9, but here’s the details again. You can insert lamps, cameras, scenes, objects, etc.
from one file into another. The best thing to do if you want to insert an object with its
materials and animations, select the “
Object
” option. All data for that object will be inserted
into the open file with that object. While in the objects menu,
right click
on all objects you
wish to insert, or type “A” for all to select all objects. Usually, you don’t insert any lamps and
cameras into a scene unless you need them. This would be a good time to discuss the
benefits of naming your objects as you create them. It makes it easier to find them later on
when they have relevent names.
Naming Objects:
Naming objects is an easy task. With an
object selected, go to the “
Edit
” Buttons
and find the “OB:” box. Type the name of the
object here. Remember that it is case
sensitive. You’ve now given your object a
name.
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