Photoshop Tutorial - The Wonders Of The Alt Key


The tips and advice on these pages are offered freely and appear in different form in many pieces of Adobe Photoshop documentation. I am in no way affiliated with Adobe. The tips that appear here are those that I have encountered during 11 years of usage and experimentation. If you find any inconsistencies, staggering omissions or the guide too hard to read, please email me at

The Option Key And How It Modifies

When I started using Photoshop, on a PC, I was always curious about the little note that would pop up on the Status Bar, telling me that pressing Control ('Ctrl / Apple ' from here on in), Shift or Alt on the keyboard would alter the tool's properties.

The Marquee Tool And Selections

The Marquee (M) tool is probably most people's first use of the alt/option key, along with the other modifiers (shift and control), to subtract from a selection. Maybe it's using it on the Layers Palette to make Clipping Masks. I doubt it. The same would appear to go for the Lasso tool (L) - hold the alt key down, click and drag on your selection and you've just deleted the shape from your selection. So the tool has been modified.

There is a second use with both the Marquee and Lasso tools - instead of holding the alt key down before clicking on the image hold it down after you have started using the tool on the image, while you are mid-drag. Using the Marquee tool you'll see the change immediately. If you're using the Lasso tool the change in behaviour is a little less obvious. Using the Lasso tool, you'll need to 'un-click' the mouse - stop dragging and release hold of the mouse button. If you're using the Polygonal Lasso tool, just keep the mouse button pressed down - the behaviour of the tool will have changed to the 'other' tool option. So if you were originally using the Lasso tool, while you've got the alt key held down it becomes the Polygonal Lasso until you remove your finger from the alt key.

These changes to the Lasso tool are particularly useful when you're using the Patch tool and want to select an area quickly.

Keyboard Shortcuts And The Alt / Option Key Modifier

Image Adjustments

The bulk of this guide is to point out that the Alt key modifies the tool or function you are using. Photoshop designers have incorporated modifiers into pretty much all the shortcuts you can use from the keyboard.

Ctrl / Apple + Shift + N will do something a little different from Ctrl / Apple + Alt + Shift + N. Give it a go. One will give you a new layer dialogue box, the other will just give you a new layer. The primary uses I've found for the Alt key are linked with Image Adjustments - Curves, Hue/Saturation and Levels. Holding the Alt key down while pressing the keyboard shortcut (Ctrl / Apple + M, U or L) for your adjustment will cause the dialogue box to pop up, but it'll already have the last Curve, Hue/Saturation or Levels choices you made set there, unless this is your first time using the function. This is great if you're just doing a certain amount of work on the images, like making images tinted using Hue/Saturation. It's also useful if you forgot to save the adjustment and think you might need to use it again.

Filters - Last Filter Modifier

So of course we can use the Alt key with Filter commands! The shortcut for Use Last Filter is Ctrl / Apple + F. Anyone who's used it knows that it's great for timesaving but only if you're not altering the level of the filter.

Quite often you'll need to use a blur on one area and a lesser blur on another. One option is to run a Gaussian Blur filter on the first area, then run another with the correct but different settings. The keyboard shortcut to do this is Ctrl / Apple + Alt + F. Without this it'd be a trawl through the Filter menu or hitting Ctrl / Apple + F to repeat the gaussian blur and a Fade - but only if the first blur is stronger. You know it makes sense!


Overall it's good to play and experiment with Photoshop. The alt key is also used to create clipping mask layers in the Layers Palette (hover between two layers and see what happens when you hold down the alt key). It reminds me that there are always ways to speed up your workflow, a lot of it through Menu, Edit, Keyboard Shortcuts - you'll see how often the alt key is used when you try and type in a command containing it!