When you want to edit part of the picture
rather than the whole thing, the way to do it is by
using the 'Quick Mask' mode.
In the picture on the right, used by kind permission
of Kev Vincent, a member of our forum,
we need to darken down the branch a little to focus
our attention on the owl.
The first thing to do is select the area we want
to work on using the 'Quick Mask' mode. Near the bottom
of the toolbox you can see an icon that looks a bit
like a camera, when you click on the icon it turns
red to tell you that you are now in 'Quick Mask' mode.
The colour patches above the icon turn to black and
white, even if you had a colour selected before. (In
versions of Photoshop before CS3 there are two buttons
side by side, you click one to go into 'Quick Mask'
mode and the other to return.)
Select the brush tool and choose a suitable 'brush
size' and 'hardness' for the job in hand. The softness
or hardness of a brush denotes the size of the fade
out at the edge. A brush with 100% hardness will have
a sharp edge, 0% hardness will start the fade out
from the centre of the brush.
Getting the hardness right is very important when
retouching photos, you don't want a completely sharp
edge, you need to zoom in on the area that you are
working on and assess how sharp the edges are that
you will be working to. When you zoom in so far that
you can see the individual pixels, you will see that
even the lines you thought were 100% sharp actually
are a little blurred.
Having selected the brush that you want, make sure
that the foreground colour is black. If it isn't click
on the bent arrow just above the colour patches to
swap the colours over. Then you can start painting
the picture. As you paint the area will fill with
a translucent red. The reason they use a translucent
red is that it is supposed to represent the 'Rubylith'
that people used to use in the old black and white
darkroom days. Rubylith, a red film, was used to create
masks because red light was invisible to the paper.
Although we are masking the bit of the picture we
want to work on, it doesn't matter because we can
reverse the selection later on. As you can see I have
not taken too much care at the edges of the branch.
This is because I know we are going to be darkening
the area and the area outside the mask is mostly black
anyway and so can't get any darker. The only part
I have taken care with is around the claws and where
the bird and the branch meet.
If you go wrong while you are painting, which you
are bound to at some time or other, click the bent
arrow to change the foreground to white. Now when
you paint the red will be removed.
Once we are happy with the mask we can unclick the
'Quick Mask' and return to normal mode. The red will
disappear and a selection marquee, a moving dotted
line, will appear. The area selected at the moment
is all of the picture that we didn't mask so, before
we can work on the branch, we need to invert the selection.
Choose 'Inverse' on the 'Select' menu or press ctrl-shift-I.
The selection is now inverted, the branch is now selected
and any effects we apply will only affect the selected
area. You can save the selection, you will see the
choice on the 'Select' menu, and it will be saved
with the file. If you have spent a long time painting
a mask then it is always worth saving it.
We could have painted the whole picture
except the branch, and then we wouldn't have needed
to invert the selection but, as you can see, it is
easier to work on the smallest part of the picture.
One thing you have to be careful of when making a
mask is leaving gaps in your painting, make sure when
you change back to normal mode that the mask hasn't
got any holes in it.
One of my favourite tricks with the 'Quick Mask'
mode is to use the 'Gradient Tool' to make a very
soft edged mask. This can be used for a number of
corrections where you want to be subtle. For instance,
when you have taken a wide picture of a room using
flash and the back of the room, which will be the
top of the picture, is under-lit. A quick mask of
the foreground will allow you to lighten up the background
to balance up the picture, a soft gradient in the
mask will ensure that the effect is subtle.
All that remains to do with our owl picture is to
open the 'Curves' dialogue box, which can be found
under 'Image'->'Adjustments' and pull the curve
down to darken the branch. In this instance I grabbed
the top of the line and pulled it down to kill the
highlights while not building up the contrast too
much. |
