Making Selections in Acorn

Acorn's Selection Palette

Acorn gives you a handful of ways to make selections on your image.

	The Rectangle selection will allow you to make rectangular selections.
	The Elliptical selection tool will allow you to make oval selections.
	The Freehand selection tool allows you to make freehand selections.  This is great if you have a selection that does not fit in a box or a square.
	The Polygonal selection tool allows you make odd selections, but by making multiple clicks.  Finish off your selection with a double click.
	The Magic Wand selection tool will select areas of the same color that you clicked on.  You can adjust the tolerance (how close a color has to be to the one you clicked on) in the selection palette.  For a live adjustment of the magic wand tolerance, you can click on the color in your image and drag the magic wand on the canvas inwards (to decrease the tolerance) or outwards (to increase the tolerance).

The shortcut key for switching to a selection tool is 'M'.  Pressing M multiple times will then cycle through all the selection tools.

To remove a selection, choose the menu item  Select ▸ Clear Selection, or use the shortcut ⌘D.

Selection Tips (!)

• To draw a perfect circle (or square), hold down the shift key after you have started your selection.

• To grow a selection from the middle of where you clicked, press the option key after you have started your selection.  

• To add to a selection, hold down the shift key before you start your selection. The selection cursor will change to include a plus sign.

• To delete from a selection, hold down the option key before you start your selection. The selection cursor will change to include a minus sign.

Preset Selections and Making Selections Fit Exact Dimensions

Acorn offers preset selection dimensions under Select ▸ Preset Selections.  If you want your selection a specific size that is not a preset, check out the online video tutorial here.  

Feathering a Selection

The Feather command will soften up the edges of your selection.  You can bring up the feather sheet from the  Select ▸ Feather menu item.  The higher the feather radius, the softer your selection will become.  The following image was made by first creating a circular selection, feathering with a radius of 10, and then choosing the Edit ▸ Fill menu item.

This image was made the same way, but by using the Inverse command under the Select menu before doing a fill: 

View Selection Clipped Out vs. Marching Ants

There are two different ways to view your selection.  The first is the traditional "Marching Ants":

You can also choose to view your selection as "clipped out":

Is there an advantage to using one or the other?  Not really- but it turns out some folks really like the clipped out look, and others like the marching ants.  You can alternate between these two options via Select ▸ View Selection As or use shortcut ⌘\.

Moving Selections

Once you have made a selection, you can move it around with the arrow keys.  In addition to this, you can hold down the ⌘ (command) key and Acorn will first cut out the selection and then move it around your image.  Letting go of ⌘ will then place your floating selection.

You can hold down ⌘ and ⌥ (option) when using the arrow keys, and Acorn will continually copy + place your selection around as you move it.  Hold down the shift key to make the selection move by 10 pixels each time you press an arrow key.

Here is a video of it in action, using a screenshot of Safari's preferences window: Command Option Move in Acorn.

The same trick works with the mouse, just hold down ⌘⌥⇧ when moving your selection with the mouse.

Addition, Subtraction, and Intersection Modes

There are four selection modes available in Acorn.  Listing them from left to right as they are displayed in the selection palette, they include:  regular, addition, subtraction, and intersection.  

Addition - When two or more selections overlap, they will be joined together to create a single selection encompassing all areas of the original selections.

       

Original Selection                                      Addition Mode

Subtraction - When you draw a selection over an existing selection, it will remove that area of the original selection.

     

 Original Selection                                Subtraction Mode

Intersection - Where selections overlap, only the area of overlap will be retained as a selection.  

                   

                                           

                                               Original Selection                 Intersection Mode

Quick Mask

The quick mask mode button can be found on the bottom left hand side of the tools palette under the color wells.  Quick mask mode is an additional way of making selections in Acorn, and can be combined with other selection tools such as the magic wand to refine a selection.  You can use the brush, eraser, and even filters when quick mask mode is enabled.  

When you enter quick mask mode, it helps to think of your selection as a virtual layer which happens to be either red tinted or clear.  Painting with the color white in quick mask mode removes the tinted color overlay.  Painting with black restores the color overlay.  Anywhere you paint with white is where your selection will be, and when you exit quick mask mode the clear overlay (which you painted with white) will change into a standard selection.  Toggle with keyboard shortcut 'q' to view your selections within and outside of quick mask. 

For more detailed information on how quick mask mode works, click here.