Running Bshow

Bshow requires Tcl/Tk version 8.3 or later. Bshow can be started from the command line with or without an image file name:


bshow file.img

Macintosh OS X

On Macintosh OS X, bshow needs to be set up to properly use it on the command line or through double clicking on the Bshow application (see Installation). On the command line, bshow has to be started through an intermediate script called bshowX:

bshowX file.img

Alternatively, bshow can be started by double clicking on its application: /Applications/Bshow.

The main window

The main window has a menu bar, a panel for the display of 2D images and slices of 3D images, and a list of controls and information fields on the right side. (The tool panel on the left is described here.)

Bshow main window

Menu bar:

Image type:

Indicates and sets the type of image displayed to specify type-specific behavior:

Averaging mode:

With the scale below one, this mode averages all the values of the pixels neighboring a display pixel. The default is to display the nearest neighbor only.


Sets the display to invert the contrast.

Status bar with 3 values:

Pixel size entry:

Pixel size is typically used as angstrom/voxel (required for CTF calculations).


The origin for the current image is displayed. This can be reset using the "Image/Set origin" menu item.

Distance reporter:

Gives the distance from the image origin, or the distance between mouse clicks when the distance measure tool is selected. For a power spectrum or Fourier transform, it gives the frequency space distance.


Range step:

The step size in the minimum and maximum sliders can be set here to allow for either fine or coarse grain control of contrast changes.


Scale the image display quickly to ± 5 standard deviation units of the average.

Image only:

Scale the image display to the current image statistic rather than the whole file.


This animates the display by going through the images or slices of a 3D image. The speed can be set to make the animation slower or faster.

Key mappings: