The extents for the zooms are pre-set, just as they are in other online mapping platforms. There are other methods of zooming but they are linked to the same zoom extents as the + and - buttons. These alternate methods include double clicking on an area, using the scroll wheel on your computer mouse, and drawing a box with your mouse while holding down the Shift key. The map may also look different depending on your monitor and its settings (resolution). You may find the right image size on another monitor or by adjusting your settings.
