Set my default image size to full size (2048 x 1536)
Set my default image size to half size (1024 x 768)
Set my default image size to quarter size (512 x 384)
Set my default image size to sixth size (341 x 256)
Set my default image size to eighth size (256 x 192)

The idea behind presenting images in this manner is courtesy of Philip Greenspun