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Applying transparency to several objects
If you group objects and apply transparency, the whole group is treated as one object and the entire
group is made transparent. But if the objects are not grouped and you apply transparency, each
individual object is given a separate transparency and you get an entirely different effect when the objects
are overlaid.
Individual transparency (left) or group transparency (right)
Mixing individual and group transparencies
You can combine the methods above to create complex transparency combinations. For example you
could set an object to 50% transparency, then group it and apply a transparency to the group as well.
You are also able to apply a transparency to a group first, and then later apply attributes to individual
objects within a group. Just hold down "Ctrl", click the individual object and change its attributes.
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