Clipping Paths and Silos
A silo is an object in a digital graphic which has been isolated from the background,
“silhouetted” so to speak. Objects must be siloed if they are to appear inside anoth-
er background. They may need to appear in a catalog, or on a web page with a patterned
background, and in order to appear professional-looking, they must be carefully ‘clipped’
oout. This can be done in numerous ways. However, by far the best way is with the pen
tool in Photoshop.
Before a good silo can be made, you must become adept at using the pen tool to manipulate
a path so that it perfectly fits around the object to be siloed. So unless you’re “Charlie Chicken
Beak”*, practice at the pen tool ‘till you get good at it.
Once your path is drawn, Double-click on it to save it as an actual path (until you do this, it’s a “work path” which is a
bizarre thing but unfortunately if you draw a new path you lose the working path) you have a host of options (I guess
hosts are to options as flocks are to seagulls). Then choose one of the following depending on the use for your graphic:
Screen (Web, Director, Flash, Powerpoint)
Command-Click the path in the path pallet, and hit Command-J
to bring the selection on to its own layer. Or,click once on the
path in the path pallet menu, and then select “Make Selection”
from the path pallet menu.
Choose O feather and Anti-Alias
from the options in the pop-up
dialogue window. Then command-J to bring the selection to it’s own layer. Hide the
background layer in the layers pallet, and go to File> Save A Copy. Choose PNG from
the list of file formats. PNG’s will work for any screen application, and are the most
commonly used 24-bit graphics files when 8-bit transparency is a necessity.
Print (Quark, InDesign, Pagemaker)
Select Clipping Path from the paths palette
menu to define the path as a clipping path. In
the pop-up dialogue box, select “Path 1” (or
whatever you named the path) from the drop-
down list, and type in ‘2’ for the device pixels
(just do it, don’t ask me why,
ask your dad). Select
“Photoshop EPS” from the list
of options (your printer will
love you if you keep every-
thing ‘Post Script’, and EPS means Encapsulated Post Script). Leave the EPS Options
pop-up options as they are.
NOTE: InDesign may support additional file-types that contain transparency; but I
haven’t experimented with it enough to talk about it and Hey, we ain’t got it anyway
so there.
ALSO NOTE: Clipping Paths are 1-bit transparency channels and as a result, your files
need to be at least 2-300 ppi or they’ll be ‘jaggy’.
Command-J will bring
any selection to it’s own
layer. Hide the back-
ground layer by clicking
the eyeball on the right
side of the pallet.
Save a copy of the file as a Photoshop
EPS for print use.
Class Notes
DMA 205
Digital Graphics
Ben Dunkle
Save a copy of the file as a PNG for
screen use.
