Clive R. Haynes FRPS
Adding & Subtracting - changing the section shape.
made a 'selection' one frequently wishes to modify the outline. This can be done
by either adding or subtracting from the shape.
for users of older versions of Photoshop pre Version 6
Using 'Quick Mask' to modify a selection
Another way of adding and subtracting is to use the Quick Mask facility. Go to the base of the Tool Bar and click on the small grey rectangle with the circular white centre. This will immediately show, in red, the area that is outside the selection.
Use a brush tool to add and subtract from the red area by selecting either black or white as the brush / foreground colour - this will add to the red area (with black / foreground paint chosen) or subtract from the red area (with white / foreground paint chosen). Swap between the two (using the 'X' key will make swapping between F/G and B/G quicker) and paint the selection to the shape required.
Click on the left-hand Quick Mask rectangle - the one with a dotted line circle, to view the selection as 'marching ants' once again. Swap back to Quick Mask mode to modify if necessary.
Dynamic Swapping between Selection Lasso Tools
This is interesting and very useful. When using the freehand lasso, the polygon lasso or the magnetic lasso tool, it's possible to swap between them for greater selection flexibility during the same act of selection. See below .........
1: Freehand to Poly. When using the freehand lasso, hold down the 'Alt' key and lo and behold, the tool changes to the polygon lasso function as long as you hold it down. Release 'Alt' and you're back to freehand mode.
2: Poly to Freehand. Conversely, when using the polygon lasso hold down the 'Alt' key and lo and behold, the tool changes to the fee-hand lasso function as long as you hold it down. Release 'Alt' and you're back to polygon mode.
3: Magnetic to Poly. When using the magnetic lasso hold down the 'Alt' key and lo and behold, the tool changes to the polygon lasso function as long as you hold it down. Release 'Alt' and you're back to magnetic mode.
4: Three in One. Now this is cleaver stuff. There is a way to swap between all selection tools above i.e.. Freehand, Poly and Magnetic. Select the Magnetic Lasso. 'Select' using the lasso as normal, to change to 'Poly' mode simply (as described above) hold down the Alt Key and 'click' from point to point. To swap to 'Freehand' mode, once again, hold down the Alt Key and 'draw' as in 'freehand'. So to use the method 'on the wing' select Magnetic Lasso and keep your finger poised above the Alt Key to swap modes as you go! To delete sections of the selection - press 'delete'. To 'select' precise horizontal, vertical or 45 degree sections, hold down the Shift Key - if necessary, in conjunction with the Alt Key as required.
Undoing & Escaping
from the 'Polygon Mesh'
Making Proportional Selections
Selections with a Proportional Square / Rectangular Shape
Selections from the 'centre' with a Proportional Shape
Transforming a Selection
the selection has been made go to:
Zoom Proportional increase / decrease in size - hold down the Shift & Alt keys, click / drag a 'handle'.
Distortion of shape - hold down the Ctrl key, click / drag a 'handle'.
Trapezoidal Distortion of Shape - hold down the Ctrl & Alt keys, click / drag a 'handle'.
'Perspective' Distortion of Shape - hold down the Ctrl, Shift & Alt keys, click / drag a 'handle'.
NB: Release the mouse button or (Wacom) pen before the Key / keys.
'Enter' to confirm the transformation or 'Esc' to cancel the operation.