The Zoom option selects the magnification of the active image window. The image is naturally 256 by 256 pixels and can be magnified by a factor of 1, 2 or 3. The image is bilinearly interpolated when magnified.
The Edit Color Bar option invokes an interactive controller for the colorbar.
The View Uncompressed Values option displays the image with the pseudo-logarithmic compression of the pixels undone.
The Invert Values option inverts the pixel values to facilitate viewing an image against a white background.