Walkthrough
: Creating a Settings File
If you want to create your
own sketch effect this walkthrough will
give you a good idea how to go about it.
Firstly you need to create
the stroke maps you want to use. These need
to be greyscale and saved as uncompressed
bitmaps. Because these maps can be repeated
over the image it's best to make sure they
are a seamless pattern. As an example, the
following are small sections from the seven
stroke maps used in the PenAndInk.sms settings
file...

level 1 stroke map
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level 2 stroke map
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level 3 stroke map
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level 4 stroke map
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level 5 stroke map
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level 6 stroke map
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level 7stroke map
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Once you have created your
stroke maps you'll need to save them. Though
you can save them anywhere the best place
to save them is in the "Stroke Maps"
folder where the Sketcher plugin is installed.
For example
"C:\Program Files\Adobe\Photoshop\Plugins\Sketcher\Stroke
Maps" or "C:\Program Files\Graphics
Programs\Shared Plugins\Sketcher\Stroke
Maps
This is the default place
the Sketcher Plugin looks for files. By
saving your sketch maps here, your sketch
effects will be easily portable to other
systems, making it easier to share effects
with others.
To set up the effect you
want it's a good idea to use a large greyscale
gradient image to experiment with, such
as something like this at 800x600 pixel
resolution...

Run the Sketcher plugin,
turn off the bumps (set Low
Bump and High
Bump to 0), and set the contrast
values to show the whole raw stroke map
data (Contr Start
= 100 and Contr
End = 0). Disable all the levels
except level 1. In level 1, choose the Media
File selector and find the stroke map you
want to use, such as "PnI1.bmp".
Decide at what minimum image intensity you
want these strokes to be applied and what
level of variation over shade you want based
on the source image intensity. For the pen
and ink effect level 1 has the following
settings
Scaling
= 34% Min Blend
= 0 (white) Max
Blend = 100 (black) Trans Start
= 100 (when source is white) Trans
End = 70 (when source is 70%
white)
and with Smoothing
set to 16, renders like this...

This introduces pen strokes
from white through to light grey (Trans
Start to Trans
End). The next level is then
created, choosing a different stroke map
("PnI2.bmp"). Level 1 is switched
off and level 2 activated, and some settings
tried. In this case...
Scaling
= 37% Min Blend
= 0 Max Blend
= 100 Trans Start
= 81 Trans End
= 40
This creates more strokes
but only when the source image intensity
is darker than white, and with Smoothing
set to 16, renders like this...

If level 1 is enabled again,
the preview shows something like this...

For each of the subsequent
levels a new stroke map is applied, introducing
crosshatched lines in darker areas. With
all levels enabled, the end stroke map,
without any contrast changes, renders something
like this...

To create the desired pen
and ink look, the contrast needs to be set
to render black lines. By setting the threshold
high (Contr End
= 85), any pixel in the stroke map of lower
intensity than 85% will be rendered black.
To balance the final image, the other end
of the scale (Contr
Start) is reduced a little to
97, so that any lighter pixels are rendered
white. The result is...

which shows different gradation
of strokes over the source intensities,
good for turning high contrast images into
pen and ink illustrations. The small thumbnail
doesn't show a clear variation over the
lighter tones and it's best to develop effects
on larger images. You may also want to experiment
on a suitable source photograph with a good
dynamic range, to give an idea how the end
result will look in a more natural context. |