Tool Bar Along the Side

There are four buttons in the tool bar along the left hand side that can be used in the image area. Select a tool by clicking on it, then use the tool on the target area as described below.

Select Tool

This is the default tool in the Visual Target Tuner. Since many apertures or the same aperture may be displayed multiple times, the Select Tool  provides the ability to select a particular aperture for manipulation. To use this tool, move the cursor inside the boundary of the aperture of interest and click it. The selected aperture will then be highlighted in red. To move or drag the aperture, simply move the cursor to the center crosshair of the selected aperture. Once the cursor displays a hand, click on the mouse button and drag the aperture. The Select Tool should be chosen when none of the other tools in this tool bar are being used so that reorientation and repositioning are enabled.

Zoom Tool

This tool provides the ability to zoom in and out of the currently displayed image. When this tool is selected, clicking on the left mouse button  zooms in to the image by a factor of two, and centers the zoomed image on the selected point. Similarly, clicking with the right mouse button zooms out by a factor of two. You may zoom in as far as 256X, or zoom out as far as 0.004X. To return your view to normal magnification (1.0X)  in one step, select "Reset View" from the "ImageTools" menu.

Centroid Tool

This tool computes the centroid for an area to improve target coordinates. First choose the target from the APT target folder which you would like updated. With the tool selected, click on a point of interest within the image. The outline of the centroid area is displayed. The VTT will compute the centroid and change the targeted position to the centroid position. The RA and Dec of the targeted position (displayed on the lower left of the window) is also updated. A radial plot profile is then displayed. Note that the data values displayed in the radial profile plot have had background subtracted and so maximum data values displayed in the image will be larger than shown in the plot.

StarView Interface

This tool allows access to the StarView Interface. With the tool selected, click on a point of interest within the image. This will bring up the StarView interface all ready to query the HST archive for past observations of the RA and Dec indicated.