View; Zoom Image Size; Scale - Meade Autostar Software Manual

4.View

The View formatting section allows you to modify how the image data is presented on the display in a
number of ways.
sophisticated image processing functions to bring out or suppress subtle details contained in the image.
You can change the size of the image, tint its display palette or annotate it.
All of the functions in the View menu affect only the image display, not the actual image data.
To access the commands you can either click on View on the Menu Bar with the mouse, use the Alt key
and the appropriate underlined letter from the keyboard, or, when available, click on the appropriate button
from the Tool Bar.
Descriptions of the Image file commands from the Menu Bar appear below. The icon from the appropriate
button from the Tool Bar also appears next to the description for your reference.

Zoom Image Size

This command allows you to change the displayed size of the image. The image can be made larger or
smaller depending on your needs. This is generally used to allow an entire image to be displayed even if
the original image size exceeds the screen size.
The Fit Window button automatically scales the image so that all of the image can be displayed in the
current window regardless of the aspect ratio of the window. This means that one axis of the image may
not completely fill a portion of the window. You will notice that the Photometry cursor is constrained from
using the area outside the actual image area.

Scale

The Scale dialog allows you to modify the contrast and brightness of the image in a variety of ways.
Scaling is a two step process. The first step is to Prescale the image. This selects the range of data to be
mapped to the 256 available levels. The second step is final Scaling of the image.
Final scaling gives you a broad range of control. You change can be as simple as a straight linear scaling
or as complex as Histogram Equalization.
When a new image is loaded, the values in this dialog box are reset to their defaults. This allows you to
initially view the image in its un-altered state.
The graph displays the transformation that will be applied to the image values when the OK button is
depressed. The horizontal axis represents the input values to the transformation, while the vertical axis
represents the resulting values. Each axis is drawn to reflect the values of the current palette. With the
normal Linear transformation each input pixel corresponds to exactly the same output value, but only
when Contrast = 1.0 and Brightness = 0.
You can think of the Contrast and Brightness controls as the variables M and B in the equation of a
straight line,
where X is the input value, M is the slope of the line, B is the zero offset and Y is the resulting value. By
varying the Contrast control you can actually see the slope of the line changing. A steep slope results in
an image that quickly varies from black to white (high contrast), while a shallow slope (less than 1.0)
produces an image which is made up mainly of gray values. Setting the Contrast to a negative value
produces a negative image.
You can lighten or darken an image, change its contrast, or run a number of
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