When set to 0, large images are not scaled to thumbnail size in memory.
When set to 1, large images are scaled to thumbnail size in memory.
Note:
Images will still be displayed as thumbnails regardless of this setting. This setting prevents unnecessary memory usage by scaling the image down in the actual memory, not just in the display.
Note:
Thumbnail images that are expanded and resized to a larger size may appear fuzzy. This is due to the compression necessary to create the thumbnails.