If data have been loaded into the program as 16-bit integers instead of bytes, they are first converted to bytes using the scaling determined by the the Low and High sliders in the Information window. For best results, be sure that the Low and High sliders are set so that images have a good contrast with a fairly wide range between the Black and White sliders. Using the autocontrast function generally leaves the sliders in positions that will allow good scaling for display. Changing the Low and High sliders will change the contrast of this image display.
The first three check boxes (View X image, etc.) turn on the display of the indicated image planes. The hot key Z or Shift+Z will turn the Z image on or off, while Shift+X and Shift+Y will toggle the X and Y image planes.
The X, Y, and Z sliders will track the current point coordinate in 3dmod image display windows and can be used to adjust both the current point position and the displayed slice in the model view window.
The X size, Y size, and Z size sliders can be used to set the size of the image that is displayed in each dimension. The displayed area will be centered on the coordinate unless that would result in the displayed size being smaller than the slider value.
The # of slices slider can be used to display multiple slices. You will be able to see through to the last slice but not past the slices, unless you turn on transparency.
Use the Transparency slider to see through the image.
The Black Level and White Level sliders can be used to adjust the contrast of the image. You can reverse the contrast by making Black be higher than White.
Press Use 3dmod Black/White to set these level sliders from the current values of the Black and White sliders in the 3dmod Information window.
The False color checkbox allows images to be displayed in the standard false color scheme. It does not appear if color images are loaded.
Turn on the Apply global clip planes checkbox to have the image clipped with the global clipping planes, if any are turned on.
The Fill button appears at the bottom if 3dmod is opened with an image pyramid and can be used to load data into the cache for the currently displayed region. This may be necessary to get a complete display of X or Y planes. When the zoom is below 1, lower resolution data are accessed if available.
Limitations of transparency: Image transparency, model object transparency, and the display of multiple slices all use a similar method for generating transparency. Displays will often not work well when you have more than one item that relies on this transparency method, because the items are not being drawn in order from back to front everywhere that they overlap. In particular, if you are displaying multiple slices, you will need to introduce significant image transparency to see any transparent objects. You may then need to adjust the black and white level sliders in this dialog to compensate for the resulting change in brightness or contrast of the image data.