Can help u with 1/2 the question:
- Setting a default zoom magnification:
Press playback button --> press info until u hit a full screen with no info view --> press F1 --> touch the screen when u wan the zoom to be centered.
A green rectangular box will appear --> rotate rear dial to the zoom magnification u wan as default --> tap shutter button.
now whenever u press the playback button and roll the back dial, u will go str to the magnification and center position set as default.
- source: fourthirdsphoto.com -
now u just need to decide whether u wan 3x , 5x or 7x magnification and u r set.