Difference between logging work time and adjusting the remaining time?

[krad23]

What is the difference between logging work time in an issue and adjusting its remaining time estimate? When use one or the other, or is it the exact same thing? This has been creating a lot of confusion in my project

[Brian Poulsen]

When we're logging time in our setup, we at the same time are forced to choose, what to do with the remaining estimate. The reason is, that the programmer needs to estimate, if the original estimate is still valid. If it is, then you could say, logging time and adjusting remaining estimate is the same. But if the task takes more time than original estimated, then it's two different things.

An example:

Let's say that the original estimate is 100 hours, and the programmer has worked 50 hours on the task, but his estimate is, that there's still 70 hours left. Then he needs to update the remaining estimate to 70 hours, but he will register, that he has worked 50 hours on the task.