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In the case of Mars, you can select among five bitmaps Two are based on visual observations made by ALPO, the Association of Lunar and Planetary Observers; one is based on Viking data. The last two are based on maps made in 1956 and 1877, showing the "canals" observers believed they were seeing at the time; they're interesting historical artifacts. Venus has two bitmaps: one shows it as a cloud-covered planet, the other as it appeared to the radar-mapping Magellan probe. If your viewing location is not on the earth, you can look back at the earth and see it with any of three different bitmaps. Most planets have one bitmap. (For those with no bitmap at all, a foot (soccer) ball bitmap is provided. This provides a sense of shape, but doesn't mislead you into thinking that a realistic map of the planet or satellite is being presented.) Alternatively, you can switch from the bitmapped views to a "solid color" mode, where it is drawn as a shaded, single-colored sphere. This option is a bit faster than the bitmapped options, though on modern systems, things ought to be fast anyway. Using the slider bars, you can modify the brightness and contrast used for the planet bitmap. The "Earthshine" option appears only for the Moon. Set "Earthshine" to 0%, and parts of the Moon and other objects that are not in sunlight will appear black. Set it to 100%, and they'll appear as if fully illuminated, and none will show phases. You usually want something bright enough that you can make out features on the dark side, but dark enough that you can tell which side is illuminated at a given time. For some special project, you may decide you want a very dark setting for realism, or a 100% setting for use in an "atlas" mode. 7d: The Camera Frame menu When you toggle the "CCD Frame" in the Display menu, Guide puts a rectangle on the screen. You can set the size, position, and tilt of the rectangle. This may be used to show the area covered by a camera or CCD image. A dialogue box will now appear with the items: Show Frame Center Frame Angle: Focal length: (Camera name) Spin Left Spin Right Show Pixels Guider Range Binning: 27.14' x 20.35'; pixels are 1.02" by 1.02" The first item simply toggles between showing and not showing the
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