APC Power Protection

Uninterruptable power supplies are essential for anyone doing essential work on their computers.
In far northern Queensland, in Australia, power problems are a regular
part of life. The region’s tropical weather patterns, including heavy
rainfalls, lightening strikes and cyclonic winds wreak havoc on
overhead power lines, causing numerous blackouts and surges. That’s why
Cairns-based freelance photographer, John Bujack, relies on a 500VA APC
Back-UPS to keep his home computer system protected against unreliable
power.

A qualified communications technician (Royal Australian Air Force
trained) for 30 years, John has been a photographer for the past 22
years. His photographs have been published in a range of well-known
Australian and overseas publications. Since photographic negatives and
transparencies deteriorate over time, especially in high humidity, he
acquired his computer system three years ago to ensure the longevity of
his work. John is currently converting his collection of photographs
into digital form and storing them onto CD-ROM disks. To undertake this
process, he uses a high-speed home-built computer with four hard
drives, a 21″ monitor, a 17″ monitor, plus the latest, top-of-the-line
Epson scanner and an Epson A3 size photo printer.

“I can’t afford to have a power interruption. Even a momentary rise or
fall in the voltage will corrupt my photographs when I am saving them.
In addition, my equipment is so valuable. I simply can’t afford to have
it destroyed by a surge,” explains John.

John first learned about the importance of power protection through the
unfortunate experience of a friend, who lost all his equipment to a
power surge.

“A friend of mine was doing a lot of consulting work on his computer
when a strong wind storm bought down one of those higher voltage power
lines onto a 240V power line. This not only burnt out the nearby
transformer block, but also sent a 1200V surge through all the local AC
power lines. My friend had a whole heap of material on his hard drive
and he lost the lot. The surge destroyed all his equipment – not just
the data but also the hardware itself.”

When it came time to acquire a computer for his photography business,
John made sure that he invested in a UPS. To select the right UPS for
his needs, John researched all the possible alternatives. Due to his
lifelong involvement in electronics, John first heard of APC through
advertisements in magazines like PC World and Australian Computer
Magazine. After carefully reviewing APC product brochures as well as
other brands, he made the decision to go with APC.

“I’m one of those people who doesn’t buy until I have read and read
everything I can about the product. APC just stood out as the best.
Everything else looked like a Mickey Mouse Meccano set,” laughs John.
The well-designed form factor of the Back-UPS, which has enough outlets
to protect all his equipment, was a particularly impressive feature.
Adds John, “Unlike other brands, APC Back-UPS just looked like it could
do its job.” Since all different kinds of power problems occur in
Cairns, John was also impressed by the ability of the Back-UPS to
provide battery back up as well as surge suppression. The Back-UPS
includes “surge only” outlets that offer protection for non-data
sensitive equipment like scanners and printers without reducing the
unit’s available power or battery capacity. This helps to maximize
battery power for equipment that needs it most like a computer and
monitor.

For John, having an APC Back-UPS connected to his computer provides
peace of mind, as it ensures he will never lose all his expensive
equipment to a power surge like his friend did. His Back-UPS unit also
allows him to study, and experiment with, the workings of Linux without
any disruptions from unexpected blackouts. Back-UPS is compatible with
and endorsed by all leading operating systems, allowing users to freely
employ the system of their choice. This feature helps John stay
protected as he moves from a Windows to Linux system.

John firmly believes that an APC Back-UPS is an integral component of any PC system.

“Anybody who has a computer needs an APC Back-UPS. A UPS is an
essential part of a computer. It’s not an option or simply a bit of
insurance or something to consider. People should see a Back-UPS in the
same light as a PC itself. If you are going to buy a computer you need
to buy a Back-UPS as well. This point cannot be stressed enough.”

As his home PC system grows, John is contemplating upgrading to a 650VA
UPS. He has been so happy with his Back-UPS he is considering using
APC’s Trade-UPS program. This will allow him to trade in his old unit
for a new unit of his choice, while receiving an important rebate.

Your editor also uses an APC Back-UPS Pro. The lights can flicker or
even go out and you never loose any critical work. There are many good
uninterruptible power supplies around, though like John, I spent my
money on an APC model. It has worked flawlessly for one and a half
years now. If you do serious computer work, they are worth the money.
Models are available for every need and to suit all the world’s power
systems.

Checkout www.apc.com

Introduction to 3D Modelling and Rendering, Part 2 â

An introduction to 3D for those new to it.
3D software offers many options in how we represent, and thus create,
the objects that go into our scenes.  In this part of the course
we examine basic object representations.

What Sorts of Objects

In most real scenes, the objects that we might want to
incorporate will be complex.  Unfortunately most 3D modellers and
renderers don’t support basic object types like ‘tree’, ‘car’, ‘person’
or ‘house’.  Such complex objects have to be created out of the
actual object types that the renderer supports.  The usual basic
objects types are flat objects, like planes and polygons, and 3D
objects like spheres, cylinders, cones, etc. Of course, you can also
obtain libraries of already created objects. Some 3D programs come with
lots of these, others few. There are web sites where people place free
‘models’ that you can download. There are also companies that
specialise in creating ‘models’ that you can buy.

Polygons, for reasons that will become clearer later in this series,
are the mainstay of most 3D modellers and renderers.  A polygon is
simply a shape made up of a number of straight lines, joined together
to define a closed shape.  The points that define the end of each
line are called a vertex.  Different programs allow variations on
the basic polygon.  Some programs require that polygons be totally
flat, that all the vertices lie in a flat plane.  Others allow
curved polygons.  Some require all polygons to have either three
or four sides.  Others allow you to construct polygons with
greater numbers of sides.  Many of these latter ones will actually
subdivide the polygon into three or four sided ones before rendering,
though this is usually hidden from the user.  One major advantage
of three sided polygons, triangles, is that they have to be flat. 
Only four sided or higher polygons can have some vertices not in the
same plane as the others.  A variation on the polygon that you
find in most 3D software is the infinite plane.  As its name
implies this plane is a flat surface that stretches off into
infinity.  Infinite planes are useful for things like water
levels, cloud layers, etc.

Polygons are defined by the x,y,z coordinates of their vertices. 
It is not unusual to be required to define the vertices of a polygon in
a particular order, such as clockwise or anticlockwise when looking at
the front face of the polygon.  Some software requires this to be
able to calculate the surface normal.  Surface normals are
incredibly important in 3D work as they are used to work out how much
light is hitting a surface, and thus it’s colour.  The surface
normal points up from the surface of the polygon.  Some software
treats polygons as single sided, other software as double sided. 
3D software that has single sided polygons will not display them if you
are looking at their back surface.  With such software if you want
a bowl, for example, you have to define polygons forming both the
inside and outside surfaces.  Software that uses double sided
polygons does not have this requirement, one layer of polygons can
represent both the inside, and outside surfaces, though this is not
natural, since the bowl walls would have no thickness.

Basic 3D objects, like spheres, cylinders, boxes and cones are also
incredibly useful.  We can construct planets from spheres and tree
trunks from cylinders, for instance.  Since these are the basic
forms used in the construction of most man-made, and many natural,
objects, they are indispensable.  Many programs, when you use one
of these, create the basic object at a standard size.  You can
then usually modify the object by stretching it into the form you
want.  Other programs allow you to stretch out the shape when you
insert it into the scene.  This stretching process allows you to
create oval footballs from a sphere, a rectangular building from a
square cube and a long spear from a squat cylinder.  Most software
gives you the choice of doing this either by typing in numbers or by
clicking and dragging.  This stage of modifying the shape of your
objects is usually much easy if you can easily switch between different
views of the object, like front, side and top, either through having
multiple views open at once or by switching views in the one window.

Boxes, spheres, cylinders, cones, polygons and text objects are the
basic construction components available in most 3D software, as shown
in this render done with Newtek’s Inspire 3D.  In some programs all
these objects are constructed out of polygons, in others they are
primitive objects that are rendered directly.  If you examine the edges
of the sphere and cone you can see that they are constructed out of
polygons. 

Creating Composite Objects

If all objects are treated as individual ones, you end up with a
heap of them to try to manage.  Since most basic objects will
actually be used to construct more complex objects it is useful to be
able to group objects together that form parts of a whole.  Thus
we might create an object ‘person’ with parts ‘head’, ‘body’, ‘arm1’,
‘arm2’, ‘leg1’ and ‘leg2’.  Then ‘leg1’ consists of ‘upper’,
‘lower’ and ‘foot’.  And so on.  Building up complex objects
out of hierarchies of other parts makes life a lot easier.  If you
want to move a whole object you can simply select the top level and
move it, knowing that all the component parts will move too. 
Otherwise you would have to separately select every component and move
them, and hope you didn’t forget some small parts.

Object hierarchies are most flexible when you can give names to each
component part.  Such hierarchies are also essential to making
character animation easier, as we will see later in the series. 
Some programs allow you to readily display object hierarchies in a
diagram form that shows the relationships between parts, similar to the
folder hierarchy views that most operating systems allow you to see for
navigation purposes.  Software that doesn’t do this is certainly
harder to use for some things.

This screen grab, from Ray Dream Studio, shows a cartoon bird and it’s
hierarchical construction.  Unfortunately too few programs provide this
sort of display.

Another type of object related to the above is a polygon mesh.  A
mesh is a set of polygons which are joined together to represent a
surface of some complexity.  A good example of this is the polygon
mesh that Bryce 3D uses to represent the shape of the landscape. 
The process of creating a polygon mesh usually does not require that
the user manually position each vertex of each polygon in t
he
mesh.  Various other convenient methods are available.  We’ll
examine these in later parts of the course.

This close-up of part of a bird model in Ray Dream Studio shows how this program tessellates spheres into polygonal meshes.



Why Are There Differences of Approach?

There are two choices the software developers have to make: what
primitive objects are to be supported; and what rendering method is to
be used?  These two questions are interrelated, as we shall see in
Part3 of the course.  The rendering method determines what actual
primitive objects the software works with to create images.  How
we want the user interface to be will determine what primitive objects
are available to the user.  For a number of reasons that we will
examine in the next part of the course, certain rendering techniques
can only actually support polygons, whilst others can actually handle
spheres, cylinders, etc.  So a program that has to use polygons
for rendering will convert a sphere into a polygonal approximation, in
a process called tessellation, before actually rendering an
image.  This creates more primitive objects to render but allows
the renderer to be highly optimised for the handling of polygons. 
A program which can directly support spheres, say, does not have to do
this conversion and thus renders fewer objects in your scene but
requires specialised program code for each object type it supports.

These internal differences in approach are what make some 3D packages
good for some types of work and others more suitable for others. 
Some will handle transparent objects superbly, other handle interior
lighting well, for example.  Some will make dealing with certain
types of objects easy, whereas others make those objects hard but
others easy.  It is for these reasons that many people working
with 3D software will use a number of packages for different parts of
the process.  Whilst this is certainly not necessary, it can be a
useful approach.  It’s the same as people using Painter for some
things and Photoshop for others, sometimes switching backwards and
forwards between the two.

The designers of 3D software have to make a complex set of choices
based on their priorities.  These choices lead to the differences
in single or double sided polygons, whether tessellation is done and
what types of rendering options are available, to pick just
three.  Some choices will speed up the execution of the program
whilst others will slow it down.  These tradeoffs account for the
huge variety that we encounter in 3D programs.

Another use for polygon meshes is to represent irregular objects, like this landscape in Bryce 3D.

The result of rendering after texture
and colour is applied looks so much more detailed and more natural than
the polygon mesh it is based on.  We’ll look at why this is so in
later parts of this course.

Simple Lighting Equipment for Digital Photography – Tungsten Lighting

Good photography is often about good lighting and in all the noise about studio flash and advanced lighting the old favourite, tungsten, often gets forgotten.
With all the hype about studio flash and the built-in flash
capabilities of modern digital cameras there is little attention paid
to an old yet faithful technology, tungsten. Yet tungsten has much to
offer. It’s cheap, continuous and very flexible, plus you see exactly
what you get. With the rise of these other forms of lighting the number
of manuafcturers of decent tungsten lighting equipment has dropped. In
this article we will look at a couple of manufacturers, PhotoFlex and
Lowel. In addition to those discussed below there are also a vast
number of simple tungsten lighting reflectors and stands available at a
very cheap price. A couple of these will do great service and cost
little. In fact you can even do amazingly well with a couple of those
portable outdoor halogen lamps they sell at hardware stores.

Tungsten lighting was always a hastle with film because it is so much
redder in colour than daylight. Thus you needed to use filters, either
on the camera lens or over the light, to make the light bluer. Since
digital cameras can readily accomodate a wide range of lighting all the
restrictions are off. You no longer need filters. On some cameras the
auto whte balance will get it right. On others set the white balance
manually to tungsten or by pointing the camera at a pure shite card
illuminated by the lights. In other cases just do this. Setup a shot
under the lighting and place a Kodak Gray Scale available from most
good camera stores in the shot. In Photoshop, Photo-Paint or other
software use this shot to set the white, black and mid gray points to
generate a correction. Save this correction and just apply it to all
the other shots made under this lighting setup.


The PhotoFlex Digital Lighting Kit

Aimed at professionals and advanced amateurs using digital cameras,
PhotoFlex’s Digital Lighting Kit includes a medium sized SilverDome nxt
softbox, a Starlight 3200 tungsten light and a four-section lightstand.
Designed to provide soft even lighting ideal for product and portrait
photography, it remains very portable and readily folded up when not in
use. It works beautifully. This is a seriously nice bit of kit, as all
PhotoFlex products are. Take down and put up time is short. A number of
accessories can be used, including a grid. I found the medium-sized
softbox an ideal size for many purposes, being a good combination of
broad and diffuse with compact and easily handled.

Note that PhotoFlex also make a huge range of other lighting accessories. All are very well made and worth a look.

www.photoflex.com

PhotoFlex’s Digital Lighting Kit offers a useful, compact and portable (when collapsed) diffuse light source.

Right – This shot was taken using simply the PhotoFlex Digital Lighting Kit almost overhead and a curved piece of mat board.


Lowel

Lowel make a very large range of tungsten, halogen and flourescent
light fixtures and accessories. What stands out with Lowel is their
small yet rugged styling that makes them ideal for location work.

Lowel’s models of interest here include the Pro-light, which is a tiny
4.3″ x 5″ x 6.7″ focusable over a 5:1 range. It can take a range of
globes, both mains and low voltage, up to 250W. The V-light is another
tiny flood light that takes a 500W halogen tube. Both of these lights
must be used with transformers as they are 110V units. The following
ones are all stock items and work off of our 240V mains. The Tota-light
is quite compact and takes up to a 800W tube. The Tota/Omni light
offers a 6:1 focusing range, from a 12 degree spot to a 53 degree flood
and 500W globes. The DP Light goes up to 1000W and focuses over an 8:1
range. The Fren-L 650 System provides a Fresnel lens, focusing over an
8:1 range and taking up to a 650W globe. The Rifa-lite is a soft light
system in three sizes up to 1000W and 32″ x 32″ front size. Lastly the
softlight 2 system takes two 800W tubes in a 28″ x 24″ x 7″ unit that
offers a puchy yet soft light.

www.lowel.com

RIFAS – The Lowel RIFA provides a good diffuse light source in three different sizes at a great price.

DP on stand – The DP light offers a good strong tungsten light that can work with a range of accessories.

TOTA – The Tota light is a good flexible unit.

OMNI – The Omni is a very compact yet flexible light source with a range of accessories to modify the light.

Kodak Gray Scale – The Kodak Gray Scale is an essential tool for all
photographers. They come in several sizes and is an essential purchase.

Introduction to 3D Modelling and Rendering, Part 1 â

An introduction to 3D for those new to it.

What is 3D?

For those of us used to working in Photoshop and Illustrator it is
important to realise that all that work is 2D, or two-dimensional.
Photographs of real objects or painting them from scratch in Painter,
they are still 2D. This is because we are either working with a pixel
representation or flat objects, like lines, text, paths, etc. This is
true even if we are attempting to simulate a 3D look.

In 3D work, or three dimensions, we are producing a description of real
objects with depth, scenes comprising many objects and the spatial
relationships between them, along with the required lighting
arrangements and viewing characteristics. The end result of 3D work is
still usually 2D. This is either a still image or an animation, but
it’s still made up of pixels. In an ideal world our output would be
three-dimensional too, as in a holographic projection or even a
sculpture. This is a limitation of the output technologies that we have
to work with at present, rather than an inherent characteristic of 3D
work. Since 3D printers exist (they are actually more like a
numerically controlled milling machine in some ways), as do using LCD
shutter glasses for direct 3D display, working completely in 3D is
possible, just not the normal use.

Deep down, usually buried deep inside the software, our 3D work
consists of rather mathematical descriptions of our scenes, such as
place a sphere of radius k, with it’s centre at x,y,z point in space
with a surface texture like stone. Thankfully, we rarely have to deal
with the numerical level unless we choose to. There are good reasons to
dive down to the numerical level at times, such as exact placement. 3D
software is largely click and drag operation these days for most common
operations. It is important to remember that we are trying to represent
things in the three-dimensional world that we are used to living in.
Just as navigating around the real world can get you lost, so is it
easy to become disoriented in 3D software.



Keeping oriented in 3D

In 3D software the convention is to use a set of three coordinates, x,
y and z. Co-ordinates can be absolute or relative. Absolute coordinates
apply to the entire world that we are creating in the computer.
Everything is specified relative to a universal origin, the centre of
your digital universe, with coordinates of 0,0,0. Positive x values may
lie to the right, negative ones to the left. Positive y values may be
up and negative ones down from the origin. Positive z may be in front
of and negative ones behind the origin. Absolute coordinates are used
to position objects in our scene, to place cameras and lights, etc.
Relative coordinates have their origin somewhere other than the world
origin. For instance, in creating an object made up of many parts it
may be more convenient to think in terms of positions relative to what
you wish to consider the centre of the object.

How the software works can have an impact on how easy it is to keep
oriented. Some programs, like Bryce, display only one window, so you
only have one view of your objects/scene at a time. Other programs,
like Vue d’Esprit or Lightwave, by default give you four views: a
front, left and top view plus the view through the main camera. This
last solution is generally preferred but does tend to work best when
you are using a large, high-resolution screen. This is why most of the
consumer level programs use the one view approach, assuming home users
have small screens, whilst professional software takes the four-view
approach.


The stages of 3D work

The following are the main stages of creating a 3D work:

1.    Create objects;

2.    Place objects in relation to each other in scene;

3.    Place light sources;

4.    Place the camera or observer;

5.    Add textures to objects;

6.    Add atmospheric effects;

7.    Render to produce a final image or animation movie.

The exact order of this sequence is partly up to you and partly a
function of the software that you are using. For instance, some
software separates the creation of objects and their placing in the
scene (as in Lightwave), others combine this into one step (as in
Bryce). Likewise, sometimes the textures are placed on objects when you
create them. But they can also be added at the scene creation stage.
Each person gradually finds their own order of working that suits their
needs and the needs of the specific project. For projects involving
many people there may be different order, or indeed some stages my be
performed in parallel, than for projects where you are doing the whole
thing. The order of steps can affect the performance of your software.
The sequence given tends to produce the least delays with most
software, for reasons that will become clear as we progress through
this series.

Creating objects and placing them in the scene is often called
‘modelling’. This is because in creating an object and then a scene we
are building a ‘model’ of it in the computer. Some software even
separates the modelling function from the rest of the software by
splitting the process into two programs. It is quite possible to do the
modelling in on manufacturer’s program and the rest of the process in
another. I quite frequently use three different programs for this
process, making use of the strengths of each, these being Poser and
Byrce and Lightwave.

Light sources and a camera are necessary if you are to see anything of
the wonderful model you have created. Light sources and cameras can be
treated in much the same way as any other object. Light sources will
have their own, special characteristics though, like the type of light
source, whether it casts shadows, its colour, etc. The camera also has
special characteristics, like its field of view, resolution of the
resulting image(s), etc.

Rendering is the process of determining what the scene looks like from
the camera position taking into account all the characteristics of the
objects, light sources and their interaction. Rendering is usually a
time consuming process for any scene of reasonable complexity. This can
vary from a ‘go get a cup of coffee’ to ‘lunch’ up to a whole week, or
more. This is one reason why high complexity rendering of still images
or animations tends to require fast computers and lots of memory. One
reason that the order with which you create your image(s) is important
is that you will usually do lots of little test renders along the way.
Thus you want to leave the details which really slow the rendering down
to as late in the sequence as possible.



Why would we want to use 3D?

We need to represent solid objects, whether in a still image for an ad
or an animation to go in a movie. Since real world objects are 3D,
there will be times when a 3D representation is needed. Sure, we can
paint or airbrush a 3D approximation but it will have a particular
look, assuming that we have the skill level to create it.
Working with
3D software creates a different look. This can vary from one with a
very computer feel to a photorealistic one, depending on the software
and what we do with it. The major advantage of working with 3D software
is that it is easy to produce changes. To change the viewpoint only
requires that we move the
camera and render. To change the lighting or
reposition objects is equally easy. So having created a scene once, we
can produce many different images from it. This is like photographing a
real scene in everything from wide-angle to close-up, and from
different positions. 3D software gives you flexibility. This very
flexibility allows you to re-purpose images. You may do an illustration
for a magazine ad and then the client comes back and wants an animation
for a TV ad, or the web. Once you have built the models, you can re-use
them repeatedly.


This screen grab of the old Metacreation’s Infiniti-D 4.5
shows a four window, working environment. Three windows give front, top
and side views whilst the fourth shows the camera view. This type of
display, common to most of the higher-end 3D packages, works best on a
high resolution, large screen.


The single view at a time display, like this one from Bryce,
works well on smaller displays. Usually keyboard shortcuts or buttons
allow you to switch between views. Whilst not as convenient as the
four-window display it is quite workable. It seems natural once you get
used to it.


This simple cartoon bird was created out of basic
object types and rendered in Infiniti-D 4.5. A background image was
used.