Alpha Transparency in Keynote 08
Quite often it is the simplest of tools that save you the most time. Having worked with Apple’s Keynote for the last year I have found the ease of use and quality of output unchallenged by any other application.
Previously we touched on how easy it is to produce interesting moving credits using Keynote and the built in Quicktime Export now Apple have introduced a great new tool to make life even easier.
If you have ever tried to import an image into keynote to suddenly discover the background clashes with your keynote theme then this tool is for you. In the past you will have been forced to take the image into Photoshop, remove the background and then export it as a transparent PNG.
Apple have addressed this extra step by the introduction of the ‘Alpha’ tool. The icon appears along the top of the Keynote window and becomes active when you click on an imported image.
As you can see in the above screen shot I have 3 great iPods but the white background looks terrible in the keynote.
To remove unwanted elements:
- Select the image.
- Click Alpha in the toolbar (or choose Format > Instant Alpha).
- Click the color you want to make transparent, and then drag slowly over it.
- As you drag, the selection grows to include the contiguous area that uses similar colors. You can control how much of the image is selected by dragging less or more.
Repeat step 3 as many times as you like.
Better still the shadow tool now works perfectly on your new cut out shape. The Alpha tool is very easy to use and my advice is to drag the wheel slowly at first and experiment with the amount of colour being removed.
This is one of the finest additions to the iWork suite! Combined with the simple animation tools its easy to make Monty Python esque animations!
[...] 1. Alpha Transparency We covered this in a tutorial last year. If you pull an image into Keynote that has a different background colour to you one used in your presentation the this tool will allow you to make the image look as if it was specifically created for your presentation. We won’t go into too much detail as you can read the full tutorial here. [...]
[...] The text version of this guide is available here. [...]