When it comes to adjusting the zoom level in the various editors, nothing beats these little known key commands for quick recall of different zoom perspectives: Save as Zoom and Recall Zoom. And there's more functionality to them than meets the eye.
Find the Key Commands
Above we see these commands as they appear in the Key Commands window. (Logic Pro > Preferences > Key Commands).
On the surface it might appear that you have only three zoom levels available for save and recall, and that these zoom views would have to be the same for all windows and editors. But looks are deceiving, because with one set of key commands you can set up and recall three different zoom settings which can be completely different for the Piano Roll, Score, Sample, and Hyper Draw Editors, as well as the Arrange area! Wow!
And it gets even better than that: the zoom settings you save for each editor as well as the arrange area are not project specific. The settings are apparently saved in Logic's preferences file, so once you establish a set of zoom levels that works for you in one project, they'll remain in force for all others.
In the Sample Editor
I find this consistency between zoom settings extremely beneficial. For example, when I'm working in the sample editor, I have three zoom levels pre-set. Zoom 1 (left) provides a highly magnified view of the amplitude. Zoom 2 (center) provides a view of the same number of bars, but without the exaggerated view of amplitude. And Zoom 3 (right) is set to zero in more closely on the individual waveforms over a mere fraction of a measure. And I settled upon these three zoom perspectives to give me quick access to waveform views I find most useful when editing dialog across multiple projects (such as when doing post production on my MIDI 101 tutorial!)
In the Score Editor
Now, to the Score Editor. Here we'll see three different zoom levels which don't correspond in any way to those I've set for the Sample Editor. On the left we see the Score Editor in the Linear View, where Zoom 1 provides a view of many bars at once. Zoom 2 (center) provides a highly detailed view which is perfect for fine-tuning the positions of score symbols. And Zoom 3 (right) is a more normal-sized view for general viewing of the score display.
In the Hyper Editor
For added perspective, below are three zoom views I've saved for the Hyper Editor. Zoom 1 and 2 (left and middle) provide a view of all Hyper Editor event definitions with the same vertical lane height but with different perspectives on the number of bars I see at once, while Zoom 3 (right) provides expanded vertical height for more precise editing.
And that's all there is to it! To learn more about Logic check out the Logic 101 tutorial.
Also check out Peter Schwartz's Essential MIDI Video Tutorial!