As you increase the number of
overlapping transparent objects on a page the complexity of
the transparency information also increases. For instance,
placing text with a drop shadow in front of the blank page
background is less complex than placing it in front of an
imported graphic where the drop shadow must be combined
with the underlying graphic for display and printing.
Use transparency effects sensibly. For example, it is
possible to feather the edge of really small, fine-serifed
type, but the resulting text will probably be impossible to
read.
Object
stacking and order and transparency
When a new
object is created on a page it is placed on top of all
existing objects. A stack of objects is created, one on top
of the other, called the stacking order. (For layouts with
multiple layers new objects are placed at the top of the
selected layer.) The stacking order becomes more
complicated when working with a group or a layer, each of
which has its own stacking order and can have transparency
applied differently to an object, a group of objects, or a
layer of objects. The stacking order is changed by moving
an object forward or backward on the layer or page. Layers,
and objects on layers are also organised in a stacking
order. The layers at the top of the list in the layers
palette are in front of the layers at the bottom of the
list.
Objects with transparency effects applied do not have to be
overlapping other objects but they often do. You could
apply an opacity value of less than 100 per cent to lighten
an object whether it is overlapping other objects or not.
However when you apply a lower opacity value you not only
make it lighter you also make it semi-opaque, which will
cause it to blend with any overlapping objects.
If you apply transparency to objects that overlap, changing
the stacking order can change the appearance of the areas
where the objects overlap. Ensure that the stacking order
produces the desired results.
In general, type should be on top of all other objects
(unless it needs to interact with transparency). Placing
text frames on top of the stacking order will help prevent
them from being involved in any transparency flattening.
>> Spot colour
