JMI Telescopes MAX Computer User Manual

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of eight, then only objects of magnitude 8.0 or brighter will 
be found.  The limiting magnitude range is from one (bright) 
to 17 (faint).  Those objects which do not have a magnitude 
defined are only found with a limit of 17. 
 
When both search parameters have been defined, press 
ENTER and the computer will display the name of the 
nearest object meeting your search criteria.  Because the 
display is updated every few seconds to indicate the 
nearest object at that instant, you may move the telescope 
until an object you wish to observe is shown.  Pressing 
ENTER will scroll the information available on the object. 
 
When no object fits the search parameters, the first item in 
the catalog is displayed (e.g.  
FOUND NGC0001
). 
 
 
ALIGN 
 
This is similar to the 
ALIGN STAR
 mode, except that an 
alignment may be done on any object in the MAX computer 
catalogs.  This includes the planets and user defined 
objects. 
 
The object used for the 
ALIGN
 mode is that last displayed 
in the 
ALIGN STAR
CATALOG
 or 
IDENTIFY
 modes.  
Use one of these modes if you wish to select a different 
object. 
 
The 
ALIGN
 mode can be used in place of, or in 
conjunction with the 
ALIGN STAR
 mode to meet the 
initial alignment requirements, as well as for subsequent 
alignments, as outlined below. 
 
Subsequent Alignments 
If, in the course of an evening's viewing, you find that the 
accuracy of guiding has decreased, you may re-align the 
telescope on an additional object to restore this accuracy.  
Such a situation is normally caused by inaccuracies in the 
manufacture of the telescope's mount, affecting its 
orthogonality (meaning all axes are perpendicular).  This 
introduces a pointing error when moving the telescope from 
one side of the sky to the other.  The MAX computer 
assumes a perfectly orthogonal mount for its calculations. 
 
If your mount is very close to being orthogonal, you will 
probably never see such an error, and should not need to 
make additional alignments.  If, however, you do wish to 
make an alignment subsequent to the initial two required, 
you should keep the following in mind.  (This does not apply 
to users of the EP or GP settings.) 
 
When making alignments, the MAX computer "sees" all 
such locations in terms of an Earth-based reference.  In 
other words, the altitude and azimuth of an object, at the 
time of its alignment
, determines its angular separation from 
another alignment object. 
 
Of course, if alignments are done near to each other in time, 
the angular separation of the alignment positions is 
essentially equal to the separation of the objects.  Note the 
distinction between alignments and objects.  Relative to the 
Earth, an object's position is changing with time, however 
the alignment positions remain fixed. 
 
Any time a subsequent alignment is made, pointing 
accuracy in the neighboring region should be improved.  
However, it is possible for such an alignment to decrease 
pointing accuracy elsewhere, even to an extent worse than 
that observed prior to the new alignment. 
 
When a new alignment is made, one of the previous two 
alignment positions — that which is least desirable relative 
to the new — is discarded.  Therefore, the angle of 
separation between the remaining previous alignment 
position and that of the new alignment becomes the critical 
factor.  If this angle is too small or too great, the overall 
pointing accuracy will degrade. 
 
For the average user, this should not be a noticeable 
problem, but if you should experience degraded accuracy, it 
can probably be eliminated by following these steps in 
selecting subsequent alignment objects: 
 
1. Recall the positions of your last two alignment objects, 
relative to the Earth (these are not their current positions). 
 
2. Try to make your subsequent alignment on an object 
which is as close to 90° (±30°) from either one of your last 
two alignment positions as possible. 
 
This process will maintain maximum pointing accuracy and 
should be followed with each subsequent alignment. 
 
 
TIMER 
(NGC-miniMAX and NGC-MAX)
 
 
This is a 24 hour event timer which displays to the second.  
Possible uses for this mode include recording elapsed time 
between occultation contacts or other astronomical 
phenomena, and exposure times for astrophotography. 
 
Upon entering this mode, the display will read: 
 
 
00 00 00.0 
 
(Tenths of a second are not displayed on the NGC-
miniMAX
.) 
 
While in this mode, use the MODE and ENTER buttons as 
follows: 
 
MODE 
This will exit the timer mode, permitting another 
mode to be chosen.  The timer will continue in 
the background, so that returning to this mode 
will accurately show the current elapsed time. 
 
ENTER 
This button cycles through a series of three 
functions: START, STOP, and RESET.