Introduction
The enormous growth of webpages in cyberspace has generated a
huge demand for graphic artists. We also live in the mids of a
3D graphics revolution, every day we hear about new exciting and
cheaper hardware for the desktop user.
I work as a Graphic Artist in Spain,
my latest works involve mixing scanned images, treated with various
special effects and filters to improve their quality, with
backgrounds made using several commercial applications for 3D
graphics.
A couple of years ago I was very happy and excited to
see the wonderful development of "The Gimp" (A Graphical
Image Manipulation Program). However in my profesional work I
mostly use photoshop, illustrator, Extreme3D, 3D Studio,
etc... a very long list of commercial software common in
the graphical design & publishing business.
Weeks ago Phil and I decided it would be very fun to test
the current status of freeware tools like Gimp and compare it
to popular publishing tools. Our idea is to have a "testing lab",
every issue of LinuxFocus
we will describe a common graphic technique, show how it is
done with commerical software, say photoshop, and them see
how it would be done with "The Gimp".
This first article explains a technique for creating an
artificial image based on a digitally scanned photo. As an example,
I made a little joke using my nephew. By the way, I am the
brother of LF editor M. A. Sepulveda.
First I will show you the final result; it was done by first
scanning a photo, repairing the color channels with Photoshop
and then cutting it with a quick mask.
Gotzilla Strikes Back!
Fixing Scanned Images
Often scanners make mistakes capturing the blue channel.
Almost all publishing software available offers the tools to
view the images by channels. Otherwise, you can check the
fidelity of your digital picture by executing an RGB separation.
Viewing the blue channel you will immediately see numerous errors in the
scanned image. More often than not these errors happen because the
quality of our scanner is not as good as we expected or
because of hardware limitations and bugs in our digital cameras.
Original scanned image
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Detail of the blue channel
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It is difficult to appreciate the ammount of noise in
the right image if you see it throgh a web browser;
most browsers only support very small color depth and resolution.
Nevertheless you probably can still appreciate
excesive deterioration of the image, it looks very noise.
I would like to explain step by step how to repair this
image because it is
very interesting and fun, however it is best to direct you
to one of the masters, Adobe's Creative Director Russell
Brown. In the page of tips of Adobe, there is ample
number of tips and techniques for repairing digital images;
it would be folish of me to repeat those notes here.
Cutting and Cutting....
Daniel's Image |
Cutting Daniel's image
from the repaired photo is not difficult. You do need
something not well-known: patience and a stable mouse!.
I supposed it would be wonderful to own a good graphic table
for computer graphics but not everyone controls the budget that
well so the only method that remains is to use the quick mask editing mode
(Adobe Photoshop). Click on the "Edit in Quick Mode" button from the
tools bar. In this mode everything you paint becomes masked (i.e.
protected); it is a very interesting technique because we can use all sort
of brushes in various modes, like brushes' dissolve-mode that makes
the masking of the selected object somewhat fuzzy.
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Let us see how we select the silhouette of Daniel: In quick mask editing mode
select a pencil an carefully draw a line around the silhouette, make sure the
line is continuous otherwise everything will break apart later, then select from
the tool box the painting can and completely fill the interior of the silhouette,
finally click on the "Edit in Standard Mode" from your tool box.
That's all folks!. Everything but the masked region is selected. Next go
to Select > Inverse to select our little friend. We are know free to copy
and paste our selection somewhere else.
When the cut of the selected object is not exactly what we wanted, it
is still possible to smooth out our selection. Just invert the selection
(Select > Invert) to grab the background of the object. Next expand
the selection size for a few pixels; How many pixels? It depends on the size
of the image, practice a little until you get a feeling for it. From the
Select menu we then choose a feather size of a few pixels (again is
dependent on the total size of the image), usually 1 or 2 pixels is enough.
Now that the selection has been adjusted we can delete the background pushing
the "Delete" key. The resulting silhouette has now a smooth shape and a
soft white aura around it.
The method of selection by "Quick Mask" editing mode is the most precise
and correct, althout it involves more work. On the other hand not every situation
requires the use of this technique for selecting an object, for example if the
colors of the object and the background are very different it is enough to use
the magic wand or a method based on selection by color, which are faster and will
save you effort.
Scenes in 3D
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The 3D scenaries can be created using various programs. For the
LinuxFocus example I used Extreme 3D 2.0 from
Macromedia.
Extreme 3D is a very useful program and much easier to use that 3D Studio, just not
as versatil. Both applications let you play with textures and lighting effects, and
our main goal is to make sure all the objects agree in color and luminosity. It is
very important to have a 3D graphics card when doing with this type of work, you will
get better performance during texture rendering.
I would recommend you read a very interesting article on the 3Dfx graphic card that
appeard in LinuxFocus Janaury 1998.
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Digital Images
You can always add extra digital images to your composition. There are many galleries
of images sold on CDs and even tons of images all through the web (off course you must
respect the appropriate copyrights). Inserting digital images from galleries into
our works can give more strength to the final composition, just make sure that the
color and luminosity are ajusted in the final work.
Final Lighting Effects
Once all our images are cut and re-scaled for the composition,
we have to adjust the scale of colors and ilumination. Perhaps this is
the most complicated part of every composition. The tools available for
it are quite simple: levels, color balance, brightness/contrast, Hue/Saturation,
equalize, variations among others. Take a little tour of them and try them to
get a feeling for their effect on colors and tones.
Here are some compositions with simple lighting effects:
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