[Brian]

Welcome to the forums, Doc411!

Effort vs. duration: here's how I think of it. Effort is the total number of person-hours required to accomplish the task. Duration would be what showed on a stopwatch at the end of the task if you started/stopped it every time someone was working on that task.

(Unless the employee never slept or took a break or worked on some other task, the actual duration of the task in your example is going to be about an hour, in other words. )

Here are a couple of examples which may help to illustrate the different options for fixed effort and/or duration...

Imagine sending a group of 10 employees to watch a 1 hour training film. The duration will be 1 hour, but the effort will be 10 person-hours. If I send an 11th person to watch that film, the effort for the task will go up, but the duration won't change, because the movie will always be 1 hour long. (For this task, the duration is fixed, in other words, but effort goes up as more people work on it.)

By comparison, imagine a task like painting a fence. If a person can paint 10 feet of fence in an hour, and I have a 80-foot fence that needs painting, I can either send a single person and have it done in one work day, or I can send multiple folks and get it done more quickly. For this kind of task, the effort is fixed (8 person-hours), but the duration isn't - it drops as you add more folks.

In OmniPlan for iPad, you can control this by tapping the task to select it, then bringing up the Resource Inspector (it's the circular button on the right with a silhouette icon). The control you want is at the bottom of the "Assign Resources" tab.

Hope that helps!