User's Guide to the Hamilton Spectrograph

Table of Contents

Quick Reference
CCD Characteristics
Grating Tilt & Dewar Height
Filter Wheel & Shutter
Calibration Sources
Photon Integrator
Image Rotator
Iodine Cell & Slit Room Controller
Guide Camera & Filter Wheel
Data Taking System
Hamilton Motor Controller
Hamilton Focus
More Info:
Spectral Format
Navigating the Spectrum
Table of Orders
Setup Procedures
Observing Hints

Data Archive
Mt. Hamilton Homepage


Showmidpoint is software used with the photon integrator to graphically display the number of counts detected by the integrator during the course of the exposure and display the photon weighted midpoint time of the exposure.

The software is started from any user computer with the command showmidpt. This brings up the GUI shown in Figure 1.

Figure 1: Showmidpoint GUI

The top section of the GUI displays a graph of the number of counts detected by the integrator as a function of time, as well as the total number of counts.

The lower section of the GUI displays the observation number along with the exposure start, photon weighted midpoint, and exposure end times. The total number of counts and missed samples are also displayed for each exposure. These figures will be displayed at the time the shutter closes and are recorded in the FITS header of the data.

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Last modified: Tue Dec 23 11:58:24 PST 2008