As a raster program, selection is one
of the most important aspects in PhotoShop. Image is formed with
the group of pixels and they need to be selected for image processing.
Adobe PhotoShop offers tools and procedures for this selection.
You need to carefully examine the image before selecting the tool. Each tool has its own way of working and you need to find out the best suited tool for selection which depends on the type of image.
Elliptical & rectangular marquee tool is used
for selection as well as to move the outline of the selection. These
tools are generally used for basic type of selections where you
don't select irregular shapes. In case of irregular shapes, Lasso
tool comes in the picture.
Lasso, Polygonal Lasso and Magnetic Lasso provides
different levels of selections. Lasso can be the best options for
freeform selection while polygonal lasso is use to set the selection
points with clicks. Magnetic lasso is an interesting tool, used
on the image with sharp contrast background.
Magic Wand is more advance Tool used for irregular
shape on the basis of similar color pixels. This tool selects the
portion painted with similar color pixels with single click. Changing
the value in Tolerance can change the degree of selection.
Quick mask mode is another advance option for minute
selection. You can paint the area of an image you want to select
and convert into selection. The main advantage of quick mask mode
is, you can use different sizes of brush for painting and also erase
the painted area if require to repaint again. This is the best option
for almost any type of complex selection.
Selections can be added and subtracted when required.
While using elliptical or rectangular marquee tools the selections
can be added with shift key and subtracted with alt key. You can
use move tool if you want to cut the selected area. Selections can
be saved and used later with Save and Load Selection. The area of
the selection can be increased or decreased precisely with modify,
expand and contract commands. Selections can be scaled or rotated
with transform command and it can be inverse to select the unselected
portion. PhotoShop provides ctrl+D to deselect any type of selection.
The choice of the selection tool and method depends
on particular requirement. And it's a matter of experience also.
The only criteria about the choice is, the selection has to be made
perfect in the minimum available time.