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SHOC

1,226 bytes added, 13:17, 1 July 2015
/* Camera */
* The next row down allows the sub-image area and binning to be chosen. For both of these, standard or custom values may be used. Smaller sub-images and higher binning allow faster image readouts, at the expense of image size and resolution. The minimum values discussed above are automatically re-calculated and displayed when the sub-image or binning is changed. NOTE: BINNING DIMENSIONS SHOULD BE EQUALLY DIVISIBLE INTO THE AREA OF THE SUB-IMAGE WHEN USING CUSTOM VALUES. An error message will appear, and will need to be cleared, when the values are not evenly divisible.
** You can visually draw a custom sub-image in the display area by clicking the white square to the right of the sub-image options. This will display a red region which can be manipulated to select the desired sub-image. Click the square again to hide the region in the display area. NOTE: YOU WILL NEED TO CAPTURE A FRAME BEFORE YOU CAN SELECT A SUB-FRAME USING THIS METHOD.
* Below this, the readout speed and preamp gain may be set. Higher readout speeds allow for shorter exposure times, but at the expense of noisier data.
* The last setting is the Electron Multiplying (EM) gain. <span style="color: red">NOTE: DO NOT USE ELECTRON MULTIPLYING MODE UNLESS YOU HAVE SPECIFICALLY OBTAINED PERMISSION FROM DR AMANDA GULBIS TO DO SO, AND YOU UNDERSTAND HOW AND WHEN TO USE IT. PERMANENT DAMAGE TO THE SENSOR CAN RESULT FROM INCORRECT USAGE. If you are using EM mode, choose the EM output amplifier, and then select a gain. BEGIN WITH LOW GAIN VALUES, BECAUSE IF THERE IS TOO MUCH SIGNAL''' YOU CAN DAMAGE THE CAMERA.'''</span>
* When setting the horizontal shift speed, preamp gain and (if using EM mode, the EM gain), note the following: Higher readout speeds allow for shorter exposure times, but at the expense of noisier data, while higher electron to ADU gain values decrease the dynamic range. Read noise and electron to ADU gain values for each mode are provided in the PDF manual. In addition to this, it should be noted that as it takes about 6 milliseconds for the top-most pixel in the frame to be shifted to the storage area and SHOC does not have a shutter. The top row of pixels in each frame will have an exposure time of about six milliseconds longer than the bottom row. Consequently although it is possible (with enough subframing and binning) to expose for less than a hundredth of a second, this is inadvisable for the above reason. Finally, as indicated above, the 1MHz CON and EM modes are both 16bit. What this means is that the mode will reach saturation at {{math|2<sup>16</sup> {{=}} 65536}} counts. On the other hand, the 3 MHz CON and EM and 5,10 MHz EM modes are all 14-bit modes and saturate at <math>2^{14} = 16384</math> counts. As the saturation limits of each mode will also depend on the electron to ADU gain, tables in the printed manual give the saturation limit in both counts and electrons for each mode.
* To get a quick view of the images that will result, press the "Preview" button. Images will be displayed in the left-hand display panel. Press "Stop" when you're done.
* To begin collecting data, press the "Start" button. The kinetic series will start, either immediately or at the designated time if using the GPS, and the data will be spooled to disk. At the same time, temporary images will be displayed in the image display area.
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