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Image area controls

Left mouse button pressed down

If you press and hold the left mouse button down in an image display area, the image pixel coordinates and pixel value are displayed in the upper left or upper right of the display area. As you move the mouse pointer with the left mouse button held down, the information is updated. This is the fastest way to see pixel values. This works in both the large and small image display areas. If the Image border fraction is less than 1, then line profiles through the displayed portion of the image are drawn on the right and bottom sides.

Left mouse button released

When you release the left mouse button in the large image display area, this selects the pixel under the mouse pointer. Information about the pixel is displayed in the scrolled text output area and usually includes pixel coordinate, pixel value, resolution, etc (see above). Furthermore, the small image display area shows a zoomed region around the selected pixel.

Middle mouse button

Use the middle mouse button to select a rectangle to zoom in on. When you press and hold down the middle mouse button a rectangle appears that indicates the area to be zoomed. Drag the mouse pointer to change the size of the rectangle. Releasing the middle mouse button displays the zoomed area. Double-clicking the middle mouse unzooms the image or refreshes an unzoomed image. If the zoom box is within a single pixel, this also unzooms the image. If you zoom large enough, the actual pixel values are displayed within the pixels. The middle mouse button works in both the large and small image display areas. (SCROLL LOCK MUST BE OFF!)

Middle FIRST, then left mouse button pressed down

This allows you to pan or move the zoom box around before actually zooming. Release the left mouse button to continue to change the size of the zoomed area.

Left FIRST, then middle mouse button pressed down

If you press and hold the left mouse button down in an image display area, then press and hold the middle mouse button down, you can pan around a zoomed image by dragging the mouse around.

SHIFT-Left mouse button

A line cursor appears and can be dragged around to measure distances in Angstroms.

CTRL-Left mouse button

A circle cursor appears and can be dragged around to measure distances and radii in pixels and millimeters.

ALT-Left mouse button

A circle cursor appears that edits the direct beam position. It can be dragged around to the new direct beam position.

Right mouse button

To cancel a cursor (line, circle, rectangle) without it performing its normal operation, press the right mouse down while the cursor is displayed. This will be a multi-button operation. Release the middle mouse button while continuing to hold down the right mouse button. The cursor will disappear. Then release the right mouse button.

Changing the color scale

If the Image border fraction is less than 1, then a color scale control pops-up when the left mouse button is pressed when the cursor is in the line profile area along the bottom of the image area. You can change the minimum scale value or the maximum scale value by grabbing near then end of an arrow and moving it left or right. Values for the displayed image are updated only when the left mouse button is released in the bottom line profile area. To cancel any impending changes, move the cursor outside of the bottom line profile area and release the left mouse button. The color scale has marks for 3 values: the image average is a solid vertical line, 1.5 sigma below the average is an ascending half line to the left of the average (it may be off scale), 5 sigma above the average is a descending half line to the right of the average (it may be off scale).

The cursor can be ANYWHERE in the bottom profile area to change the color scale. It need not be directly on the color scale.

Example of color scale control.

Keyboard commands in the image areas

If the keyboard focus is in the large or small image area, then a few keyboard commands can be used. One way to set the keyboard focus in the small image area is to click on the Scan No. text field, then press the Tab key. To set the keyboard focus to the large image area, select the scrolled text area, then press Ctrl+Tab. Keyboard commands are:

>, G, <, L

These zoom (>, G) or unzoom (<, L) the displayed image by a factor of 2.

I, J, K, M. arrow keys

These shift or pan the view. The shift is one-tenth of the viewed area or 1 pixel, whichever is larger.

-, delete, backspace

These delete the spot in the reflnlist closest to the cursor position. You must File/Write refln list... to save the edited reflnlist to a file.

+, insert

These add the last successfully integrated spot to an existing reflnlist. You must File/Write refln list... to save the edited reflnlist to a file.