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the solid and dashed lines.  If  B  and  G  are quite close to the solid lines, there may be an objectionable amount of vignetting for objects near the edge of the field.  In this case, baffle  G  should be located a little farther out from the main structure of the telescope tube.  When a satisfactory location for baffle  G  has been found, points  B  and  G  are marked on the layout.  The locations of all the other baffles are then decided upon and laid out in plan approximately as shown in Figure 5

     Once the locations of all baffles has been decided upon, the baffles themselves can be designed.  The outside outline of each baffle must conform to the inside cross section of the telescope tube at its location.  These can be laid out to scale as shown in Figure 5.  From the plan view we locate the center and radius of the cross section of each cone of rays that passes through a baffle.  These centers are the located on the baffle layout and the cross sections are drawn in as circles.  Points  B  and  G  locate the straight portions of the inside outlines of baffles  B  and  G.  The rest of the inside outlines are drawn as arcs of circles which clear the cones of rays by about one-inch, all the way around.  This is done so that possible convection currents in the air inside the tube can get around the edge of a baffle without being pushed too far into one of the light paths. 

     If the telescope is intended for use on bright objects only, such as the moon and planets, the baffle system may be omitted entirely.  However, even on these objects, a baffle system will give more pleasing views.  A very good compromise between the complete baffle system which has just been described and no baffles at all, is a muffle with baffle  G  on its front end plus just the straight portion of baffle  B.  These two baffles by themselves will screen out all direct starlight from the eyepiece, and will give a field of view which