The “Air mass curve” dialog is used to display a curve of air mass coefficients and altitudes as a function of time. These values to useful in data post-processing to compute the extinction coefficients.
Making a graph of air mass coefficients
(1) The actual data set is shown here.
(2) The list of available data sets is displayed here.
(3) You can switch the labels on the X axis between Julian date (JD) or date and time (UTC).
The Statistics is a tool that computes and shows the minimum, maximum, sample mean and standard deviation.
To activate the tool:
If no points are selected, all points in the data set are included in the computation. To restrict the data for the statistics, press and hold the Shift key and draw a rectangle in a graph while you keep the left mouse button pressed down.
The Measurement tool displays two cursors in the graph. The cursors can be adjusted by dragging them using the left mouse button. The position of each cursor, their distance and statistics for the data between cursors is presented.
To activate the tool:
From the local menu, select Tools ‣ Measurement. A new panel on the right side of the preview window appears.
Measurement tool
(1) Choose the axis you want to measure.
(2) Positions of the cursor 1 and 2 are displayed here.
(3) Distance between cursor 1 and 2.
(4) When cursors are defined on the independent (X) axis, number of points (frames) between cursor 1 and 2 are displayed and also minimum, maximum, mean value and sample deviation are presented.
See also