Bitmap Export Dialog Box - Control Buttons
These buttons are between the two Preview windows on the Bitmap Export and Create Bitmap Copy dialog boxes.
Zoom - click on a preview to zoom in. Shift-click to zoom out. Drag over an area of the preview to zoom into that area.
Push - lets you drag the image around in the Preview window.
Zoom to Fit - scales the preview image to fit the window.
100% - scales the image to full-size (100%)
1:1 - has no effect for GIFs. Scales the image so one pixel in the bitmap is one pixel on screen. This is useful for previewing detail in the bitmap.
Color Selector - moving the pointer over the image highlights the color under the pointer. Click to select that color in the palette. (Has no effect for PNG/BMP True Color.)
Note:
The Zoom options just change your view onto the preview. They do not change the dimensions of the bitmap exported to disk. Use Bitmap Size if you need to change the size of the exported bitmap.