This tab sheet in the Settings dialog, you must specify the parameters of the CCD camera used for the observations.
在这个标签里，你应该指定你观测用的CCD的各种参数。
In this section, you must specify some details on the scale and orientation of the CCD images. The values will be used by the program when it tries to match the reference stars in the star catalogue with the stars recorded in the CCD images. Providing accurate values, and setting the variations for focal length, orientation and pointing as small as possible (but still as large as needed), will prevent problems with the reference star identification and will also save runtime.
在这里，你需要指定一些关于CCD图片比例及方位角的设置。这些设置将对软件处理及对比参考星有很重要的作用。合适得设置（尽量小但又尽量足够）焦距、方位及瞄准点误差可以避免匹配参考星出现问题，也可以有效的节省程序运行时间。
Focal Length: The focal length (in millimeters), and the possible variation from the nominal value (in percent). Note that the true focal length of commercial telescopes sometimes differs significantly from the nominal focal length. Focusing reflectors by changing the spacing between the primary and secondary mirror (as in most commercial Schmidt-Cassegrain telescopes) also changes the focal length. Furthermore, many telescopes have slightly different focal lengths at different temperatures. Set the variation allowed for the focal length to compensate for these effects. Setting the variation as small as possible (though as large as needed) will increase the efficiency and reliability of the reference star match.
Position Angle: The orientation of the image, and the possible variation from the nominal value, both measured in degrees. The orientation is specified by the position angle: "North up" corresponds to a position angle of 0°, "East up" to 90°, "South up" to 180°, and "West up" to 270°. Setting the variation as small as possible (though as large as needed) will increase the efficiency and reliability of the reference star match.
Pointing: The uncertainty of the center coordinates specified for the images at the beginning of each data reduction process. Thus, the value specified here is not strictly the pointing error of your telescope mount. The software will read reference star data from the star catalog for a field corresponding to the field of the CCD frame, enlarged by the value specified here on each side of the frame. Setting this value as small as possible (though as large as needed) will increase the efficiency and reliability of the reference star match.
Flip Horizontal: Check this box if all images should be flipped horizontally after loading. This is sometimes necessary when using a star diagonal, an adaptive optics device, or if the CCD operates directly at the prime focus of the telescope.
Flip Vertical: Check this box if all images should be flipped vertically after loading. This is sometimes necessary with FITS files, as the FITS standard does not define if the first line read from the image file is the line at the top, or at the bottom of the image.
Auto-Save FITS with WCS: If this option is checked, FITS images will automatically be saved with WCS information immediately after data reduction. Note, however, that all files will be saved as 16bit Integer FITS files, even if the original image was a 8bit or 32bit file. In case of 32bit images, saving the image with 16bits per pixel will possibly loose some information present in the original image!
Offset from UT: The offset of the time read from the image file header from the Universal Time (UT). If the CCD software writes local time to the file header, enter your time zone here. (If necessary, take Dailight Savings Time into account here, and remember to change the offset when switching to Daylight Savings Time or back!). If the time in the file header corresponds to UT, enter zero. For FITS files in which the time is explicitely specified as referring to Universal Time (UT) in the file header, this correction is not applied.
Precision: The precision of the timestamp in the CCD file header. The software will write the time for the observations to a precision of six deimal digits to the MPCReport file if a value of less than 1 second is specified. By default, the time should be reported to the MPC with a precision of five decimal digits, so usually, a value of 1 second is set in this field. An additional digit may be justified for observations of very fast moving objects.
The precise value specified in this field will be used in the new, proposed format for the MPCReport.
Skip checking of Time after Loading: Selecting this option will skip the manual checking of date and time (using the Edit Image Parameter dialog) after loading each image. Please set this option with great care, and skip the check only if all your images have a precise time stamp from a reliable source (e.g., radio controlled PC clock) in the file header.
Pixel Width: The width of the CCD pixels, in microns.
Pixel Height: The height of the CCD pixels, in microns.
Note: If you are using FITS files that contain the XBINNING and YBINNG keywords and associated data (binning factor) in the file header, the software will automatically recoginze binned images, and multiply the physical pixel size specified here by the binning factor, to get the logical pixel size of the binned image. If you are not using FITS files, or the FITS file header does not contain the XBINNING and YBINNG keywords, you need to specify the the logical size of the binned pixels here. (For example, if the physical pixels are 9µm x 9µm in size, and you use 2x2 binning, enter 18µm for the width and height of the pixels.) Also note that the logical pixel size of the image is calculated on loading the image, i.e., the pixel size specified here is used as the image file is read. If you change the pixel size while you have some image loaded, the new pixel size will not be applied to the currently loaded images!
Saturation: The saturation level. Pixels with values higher than the saturation level will be excluded from the data reduction process. If you use calibrated images (i.e., dark frame and/or flat field correction applied before reading the images with Astrometrica), enter a value somewhat lower than the true saturation level of the original images, because the software used for calibration will possibly change the original values of satured pixels during dark frame subtraction and/or flat field correction. If you specify a value larger than the actual saturation level, it will cause the software to find multiple false detections around bright stars, and eventually the image alignment and reference star match may fail.
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