From the plugin source: If not defined, these values are set to the values of the speed and easing options, respectively.

The speedOut and easeOut properties are applied when a slide is transitioned out. This is where things start to get fun.

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Custom transitions let you unlock the full power of the Cycle Plugin. Everything you've learned so far has been built on custom transitions under the hood. To understand how transitions really work, and how you can customize them, you need to understand five more option properties: This property is a be-kind-to-IE property.

It is necessary to keep IE happy when animating out the first slide. Any properties that are animated must have initial values, otherwise IE will bork. These values can be defined in CSS, but this property removes the dependency on the external CSS definition.

You may have just realized that this gives you full control over both the incoming slide and the outgoing slide. You can choose which properties to animate, where the slide should start, etc.

Use these options, along with the custom fx option, to create transitons that use different effects for the in and out slides. Internet Explorer will make you pay if you define properties in the animIn or animOut options that are not animatable.

For example, don't try to animate the z-index property!