Meade 2045 User manual

OPERATING INSTRUCTIONS
Meade Instruments Corporation
1675 Toronto Way, Costa Mesa, California 92626 U.S.A.
[phone]
MEADE MODEL 2045
4" SCHMIDT-CASSEGRAIN TELESCOPE

TABLE OF CONTENTS
Introduction
Standard Equipment
Setting Up The Telescope
Telescope Operation: Your First Observations
Focusing
Magnification
The Viewfinder
Celestial Coordinates
Lining Up With The Celestial Pole
Latitude Ranges
High Latitudes
Low Latitude Balance Weight
Precise Polar Alignment
Electronic Motor Drive
Setting Circles
Observing with the Telescope
Telescope Maintenance
Basic Specifications: Model 2045

MEADE MODEL 2045:4" SCHMIDT-CASSEGRAIN TELESCOPE
INTRODUCTION
The Meade Model 2045 permits a very wide range of serious astronomical and terrestrial applications —
and in an extremely compact and portable optical/mechanical package. The advanced
Schmidt-Cassegrain mirror-lens ("catadioptric") optical design of the Model 2045 enables a 40” effective
optical tube length to be compressed into an actual tube length only 10" long — and with no sacrifice
whatsoever in the most demanding performance requirements. The capabilities of the instrument are
essentially limited not only by the telescope, but by the acquired skills of the observer and photographer.
Do take time to read this manual thoroughly so that you will be fully acquainted with the many important
features of the telescope, as well as with the auxiliary equipment and accessories available for advanced
applications.
STANDARD EQUIPMENT
• 4” Schmidt-Cassegrain optical tube assembly and fork mount with pulse motor drive system
• 1 Eyepiece — MA25mm 1-1/4" O.D.
• 1 eyepiece holder/diagonal prism assembly
• 5x24mm viewfinder
• 3 thread-in tripod legs (2 fixed length legs; 1 adjustable length leg)
• Dust covers (front and rear)
• Battery pack with cord
• Hardware package
SETTING UP THE TELESCOPE
The basic Model 2045 telescope is shipped as a completely assembled instrument. After removing he
telescope from its shipping carton and carrying case, familiarize yourself with the various controls and
accessories (See Fig. 1).
The eyepiece holder/diagonal prism threads directly onto the rear cell thread of the telescope and, in turn,
accepts the supplied eyepiece. The 5x24 viewfinder attaches to the rear portion of the telescope with the
supplied hardware (see (1), Fig. 1).
For astronomical observations, the diagonal prism provides a comfortable right-angle viewing position.
Note, however, that although the image appears correctly oriented up-and-down, it is reversed
left-for-right. For terrestrial observations, where a fully-corrected image orientation (both up-and-down
and left-for-right) is desirable, the optional #928 45* Erect-Image Roof Prism and eye piece holder (1-1/4")
should be ordered separately. The standard diagonal prism is also well-suited for many terrestrial
observations. Eyepieces are held in place in the diagonal prism with a moderate tightening of the small
thumbscrew.

Fig. 1 — Meade Model 2045
(1) Viewfinder
(2) Declination Lock
(3) Declination Setting Circle
(4) Motor Drive Base
(5) Declination Slow-Motion Control
(6) Adjustable Tripod Leg
(7) Right Ascension Lock
(8) Right Ascension Setting Circle
(9) R.A. Slow-Motion Control
(10) Tube Adapter
(11) Eyepiece-Holder/Diagonal Prism
(12) Eyepiece
(13) Fixed-Length Tripod Leg
(14) Tripod Adapter (Optional)

TELESCOPE OPERATION: YOUR FIRST OBSERVATIONS
With the telescope standing upright on its drive base (i.e. without the 3 tripod legs attached), the
eyepiece-holder/diagonal prism attached, and with the MA 25mm eyepiece inserted into the diagonal
prism, you are ready to make observations through the telescope.
WARNING ! NEVER POINT THE TELESCOPE DIRECTLY AT OR NEAR THE SUN, OR ATTEMPT TO
OBSERVE THE SUN, EITHER THROUGH THE MAIN TELESCOPE OR THE VIEWFINDER, WITHOUT
A PROPER PROFESSIONAL QUALITY SOLAR FILTER! INSTANT AND IRREVERSIBLE INJURY TO
YOUR EYE MAY OTHERWISE RESULT!
By unlocking the R.A. lock (7), Fig. 1, the telecope may be turned rapidly through wide angles in Right
Ascension (R.A.) The reason for the terminology "Right Ascension" and its complementary term
"Declination" will be made clear further on in this manual. For now, "Right Ascension" simply means
"horizontal" and "Declination" means "vertical."
DO NOT ATTEMPT TO MOVE THE TELESCOPE MANUALLY IN A HORIZONTAL DIRECTION WHEN
THE R.A. LOCK IS IN THE FULLY "LOCKED" POSITION, AS SUCH OPERATION MAY RESULT IN
DAMAGE TO THE INTERNAL GEAR SYSTEM.
Release the Declination lock (2), Fig. 1, by rotating the control lever in a counterclockwise direction. This
permits sweeping the telescope through wide angles in Declination.
DO NOT ATTEMPT TO MOVE THE TELESCOPE MANUALLY IN A VERTICAL DIRECTION WHEN
THE DECLINATION LOCK IS IN THE "LOCKED" POSITION.
To use the Declination fine-adjust, or slow-motion control, lock the telescope in Declination using the
Declination lock (2) Fig. 1, and turn the Declination slow-motion knob (5), Fig. 1.
NOTE THAT THIS DECLINATION SLOW-MOTION CONTROL HAS A FIXED TRAVEL LENGTH,
LIMITED BY THE MOTION OF A TANGENT ARM (LOCATED INSIDE THE FORK TINE). DO NOT
FORCE THE DECLINATION SLOW-MOTION KNOB WHEN THE TANGENT ARM HAS REACHED THE
END OF ITS TRAVEL. IN THIS CASE, TURN THE DEC. KNOB TO RETURN THE TANGENT ARM TO
THE MID POINT IN ITS TRAVEL RANGE, UNLOCK THE DECLINATION LOCK AND RE-CENTER THE
TELESCOPE MANUALLY.
With the above mechanical operations in mind, select an easy-to-find terrestrial object as your first subject
— for example a house or building perhaps one-half mile distant. Unlock the Dec. lock (2), Fig. 1, and
R.A. lock (7), Fig. 1, center the object in the telescopic field of view and then re-lock the Dec. and R.A.
locks. Precise image centering is accomplished by using the Dec. and R.A. slow motion controls (5) and
(9), Fig. 1.
FOCUSING
The focusing kob is located at the "4 o’clock" position as you face the rear cell of the telescope. Focusing
is accomplsihed internally by a precise motion of the telescope primary mirror, so that as you turn the
focus knob, there are no externally moving parts.
Focusing the telescope from its nearest possible focus point (on an object about 15 ft. away) to an object
at infinity requires a fairly large number of rotations of the focus knob. The focuser is designed to provide
an extremely sensitive means of bringing an object into precise, sharp focus. After a specific object has
been brought into focus, closer objects require turning the focus knob clockwise; more distant objects
require turning the focus knob counterclockwise.
It is possible that you may notice a very slight shifting of the image as you focus, particularly at high

powers. This image shift is caused by very small lateral motions of the primary mirror as it moves toward
or away from the secondary mirror during the focusing procedure.
MAGNIFICATION
The magnification, or power, of the telescope depends on two optical characteristics: the focal length of
the main telescope, and the focal length of the eyepiece used during a particular observation. The focal
length of the Model 2045 telescope is fixed at 1000mm. To calculate the power in use with a particular
eyepiece, divide the focal length of the eyepiece into the focal length of the main telescope. For example,
using the MA 25mm eyepiece supplied with the Model 2045, the power is calculated as follows:
Power = 1000mm + 25mm = 40X
Similarly, with an MA 9mm eyepiece, a magnifying power of 1000mm/9mm, or 111X, results. The type of
eyepiece (whether "MA” Modified Achromatic, "OR" Orthoscopic, "SP" Super Plossl, etc.) has no bearing
on magnifying power but does affect such optical characteristics as field of view, flatness of field and color
correction.
When beginning observations on a particular object, start with a low-power eyepiece. Get the object well
centered in the field of view and sharply focused. Then try the next step up in magnification. If the image
starts to become fuzzy as you work into higher magnifications, then back down to a lower power. The
atmospheric steadiness is not sufficient to support high powers at the time you are observing. Keep in
mind that a bright, clearly resolved but small image will show far more detail than a dimmer, poorly
resolved larger image.
Optional eyepieces and the #126 2X Telenegative Amplifier are available for higher and lower powers
through the telescope.
THE VIEWFINDER
The 5x24mm viewfinder has been prefocused at infinity. Should this focusing need adjustment for your
eye, loosen the knurled collar at the objective lens end of the viewfinder (the end opposite where you
observe through the finder), enabling rotation of the objective lens cell, forward or backward for precise
focusing. Tighten down the knurled collar against the objective lens cell to lock the focus in place. Note
that no focusing is possible or necessary at the eyepiece end of the finder scope. The viewfinder will
require alignment, or collimation, to the main telescope. Using the supplied 25mm eyepiece, point the
main telescope at some easy to find land object (e.g. the top of a telephone pole or corner of a building)
at least 200 yards distant. Center a well-defined object in the main telescope. Then, using one of the hex
wrenches provided, tighten or loosen, as appropriate, the 3 collimation screws located on the finder’s rear
bracket ring until the cross hairs of the finder are precisely centered in the main telescope. With this
collimation accomplished, objects located first in the wide-field viewfinder will then be centered in the
main telescope’s field of view. Note that images seen in the viewfinder are upside-down from their
counterparts viewed through the main telescope with diagonal prism.
CELESTIAL COORDINATES
For terrestrial observing, setting the Model 2045 flat on the bottom of its drive base is a completely
satisfactory method for tracking or observing objects in the telescope. For astronomical observing,
however, the situation is quite different: objects move fairly rapidly through the field of view (due to
Earth’s axial rotation) and they move at an angle to the horizon, depending on the observer’s latitude. It
is for these reasons that the Model 2045 is equipped with two highly convenient features: a means of
tilting the entire telescope to an angle (thereby facilitating astronomical tracking); and an electronic pulse
motor drive for automatic tracking. Before discussing these points, some background in celestial
coordinates is required.
Analogous to the Earth-based coordinate system of latitude and longitude, celestial objects are mapped
according to a coordinate system on the "celestial sphere," the imaginary sphere on which all stars

appear to be placed.
The Poles of the celestial coordinate system are defined as those two points where the Earth’s rotational
axis, if extended to infinity North and South, intersect the celestial sphere. Thus, tHe North Celestial Pole
is that point in the sky where an extension of the Earth’s axis through the North Pole intersects the
celestial sphere. In fact, this point in the sky is located near the North Star, Polaris.
On the surface of the Earth, "lines of longitude” are drawn between the North and South Poles. Similarly,
"lines of latitude" are drawn in an East-West direction, parallel to the Earth’s equator. The celestial
equator is simply a projection of the Earth’s equator onto the celestial sphere. Just as on the surface of
the Earth, imaginary lines have been drawn on the celestial sphere to form a coordinate grid. Celestial
object positions are mapped on this grid in the same manner as positions on the Earth’s surface are
specified by their latitude and longitude.
The celestial equivalent to Earth latitude is called "Declination,” or simply "Dec.," and is measured in
degrees, minutes and seconds North ("+") or South of the celestial equator. Thus any point on the
celestial equator (which passes, for example, through the constellations Orion, Virgo and Aquarius) is
specified as having 0°0 min 0 sec Declination. The Declination of the star Polaris, located very near the
North Celestial Pole, is +89.2°.
The celestial equivalent to Earth longitude is called "Right Ascension," or "R.A.," and is measured in
hours, minutes and seconds from an arbitrarily defined "zero" line of R.A. passing through the
constellation Pegasus. Right Ascension coordinates range from o hr o m i n O sec up to (but not including)
24 hr o m i n o sec . Thus there are 24 primary lines of R.A., located at 15° intervals along the celestial equator.
Objects located further and further East of the prime (o hr o m , n O sec ) Right Ascension grid line carry
increasing R.A. coordinates.
With all celestial objects therefore capable of being specified in position by their celestial coordinates of
Right Ascension and Declination, the task of finding objects (in particular faint objects) in the telescope is
greatly simplified. The setting circles of the Modei 2045 may be dialed, in effect, to read the
object-coordinates, and the object found without resorting to visual location techniques. However, these
setting circles may be used to advantage only if the telescope is first properly aligned with the North
Celestial Pole.
LINING UP WITH THE CELESTIAL POLE
Objects in the sky appear to revolve around the celestial pole. (Actually, celestial objects are essentially
"fixed," and their apparent motion is caused by the Earth’s axial rotation). During any 24-hour period,
stars make one complete revolution about the Pole, describing concentric circles with the Pole at the
center. By lining up with the telescope’s polar axis with the North Celestial Pole (or, for observers located
in the Earth’s Southern Hemisphere, with the South Celestial Pole), astronomical objects may be
followed, or tracked, simply by moving the telescope about one axis, the polar axis. In the case of the
Meade Model 2045, this tracking may be accomplished automatically with the electric motor drive.
For the purposes of casual visual telescopic observations, lining up the telescope’s polar axis to within a
degree or two of the Pole is more than sufficient. With this level of pointing accuracy, the telescope’s
motor drive will track accurately and keep objects in the telescopic field of view for perhaps 20 to 30
minutes.
To line up the telescope with the North Celestial Pole, follow this procedure:
1. Attach the 3 tripod legs to the telescope, as shown in Fig. 1. Note that one leg is adjustable in length.
This leg should be threaded into the central hole on the underside of the drive base.
2. The polar axis of the telescope is an imaginary line running through the adjustable tripod leg, up through
the center of the drive base, and up between and parallel to the two fork arms. The long arrow in Fig. 2
indicates the polar axis. (It is around this axis that the telescope turns in Right Ascension). In Fig. 2, the
telescope is oriented so that the main optical tube is also aligned with the polar axis. With the telescope
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position as in Fig. 2 (careful eye alignment to make the main tube parallel to the fork arms is sufficient),
perform these two operations:
a. Turn the entire telescope on its tripod until the telescope tube is pointing due North.
b. Lengthen or shorten the adjustable tripod leg (6), Fig. 1, until the angle it makes with the horizontal
is equal to your latitude. (Most road maps show latitude). Use a protractor for this operation: hold the
protractor up to the tripod leg and adjust the leg length until the leg angle to the horizontal equals your
latitude.
In Fig. 2, note that the telescope is pointing North and the adjustable tripod leg has been set to make the
correct latitude angle with the horizontal as described in steps (a) and (b). The adjustable leg is locked to
the correct length by tightening the small thumbscrew located at the lower end of the leg.
The above procedure is approximate, but is more than adequate for visual observations through the
telescope and for many astrophotographic applications.
If the polar alignment procedure has been properly performed, then the North Star (Polaris) will be visible
in the field of view of the viewfinder, with the telescope again oriented as shown in Fig. 2. In summary, the
polar axis is indicated by the long arrow lined up with the adjustable tripod leg. This axis should (a) point
North; (b> make an angle with the tabletop (horizontal) equal to your latitude. To accomplish (b), lengthen
or shorten the adjustable tripod leg
Figure 2: Lining Up With The Pole
With the telescope thus aligned to the Pole, the position of the tripod remains fixed during all subsequent
observations through the telescope. Loosen the R.A. and Dec. locks each time you wish to move the
telescope manually to locate a new object, then re-tighten these locks once the object is in the telescopic
field of view. When the electronic pulse motor drive is plugged in, the telescope automatically tracks
astronomical objects each time you re-tighten the R.A. lock.
As a separate procedure, during your first use of the telescope, you should check the calibration of the
Declination setting circles (see (3), Fig. 1), located at the top of the two fork arms. With Polaris in the field
of the viewfinder or in the field of the main telescope if properly polar aligned, loosen slightly the knurled
central hubs of both Declination setting circles. Now turn each circle until each reads 89.2‘, the
Declination of Polaris, and then tighten down the knurled knob, avoiding any motion of the circle.
Once the correct length of the adjustable tripod length for proper polar alignment has been
determined,make a small mark on the tripod leg indicating the proper leg extension position. The tripod
leg may now be extended to the correct position without resorting to the entire procedure above. Simply
point the polar axis due North and extend the tripod leg to the pre-marked location. If you move your
observing location significantly, you will need to re-set the tripod to the correct angle. (Approximately 70
miles movement in North-South observing position is equivalent to 1* in latitude change.)

LATITUDE RANGES
Note that the adjustable leg may be varied in length to accommodate a wide range-of observing location
latitudes. In addition, this tripod leg may be threaded into any one of three holes on the underside of the
drive base to achieve an even wider range of latitude angles.
If the adjustable tripod leg is threaded into the top mounting hole (on the underside of the drive base),
then the adjustable leg covers a latitude range of from 32’ to 49"; in the middle (central) hole, it covers a
range from 27’ to 42"; and in the bottom hole, it covers a range from 21 ’ to 34".
HIGH LATITUDES
At high latitudes, the standard equipment adjustable tripod leg may not permit a sufficiently high angle for
the polar axis to be in correct alignment. In this case (at latitudes higher than about 49") the optional
"Center Tripod Leg for High Latitudes" (47’ to 69°) should be used. The high latitude adjustable leg can
be used for latitudes from 47' to 69’ as follows: with the leg in the top mounting hole, the latitude range is
60° to 69’; in the middle (central) hole, the range is from 53’ to 64°; and in the bottom hole, the range is
from 47" to 56°.
LOW LATITUDE BALANCE WEIGHT
When the Model 2045 is used at low latitudes, the telescope is tilted to a large angle. At such an angle,
the telescope may become unstable and the adjustable tripod leg may tend to lift off of the tabletop. To
prevent this instability at lower latitudes, the optional Low Latitude Balance Weight is available.
Unthread the adjustable tripod leg from its position in the drive base and slide the Low Latitude Balance
Weight onto the tripod leg. This balance weight should be placed on the adjustable tripod leg as close to
the lower (rubber tip) end of the leg as possible. After positioning the balance weight, fix it in position by a
moderate tightening of its thumb screw.
The Low Latitude Balance Weight is recommended whenever the observing location is at 30’ latitude or
lowertor visual observations or when the telescope is being used with a camera attached, at observing
latitudes of 35 * or lower.
PRECISE POLAR ALIGNMENT
Unless you intend to engage in long exposure astrophotography, it is not necessary to follow the precise
polar alignment procedure described in this section.
Notwithstanding the precision and sophistication of the quartz time base drive system supplied with the
Meade Model 2045, the fewer tracking corrections required during the course of a long-exposure
photograph, the better. (For our purposes, "long-exposure" means any photograph of about 10 minutes
duration or longer). In particular, the number of Declination corrections required is a direct function of the
precision of polar alignment.
The procedure described here should be implemented only after the alignment procedures of the
preceding section have first been carried out.
Precise polar alignment requires the use of a cross hair eyepiece. The Meade MA 12mm Illuminated
Reticle Eyepiece is well-suited in this application, but you will want to increase the effective magnification
through the use of the #126 2X Telenegative Amplifier. Then follow this procedure:
1. Place the illuminated reticle eyepiece (or eyepiece/Telengegative Amplifier combination) into the
diagonal prism of the telescope.
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2. Point the telescope with the motor drive running, at a moderately bright star near where the
meridian (the North-South line passing through your local zenith) and the celestial equator
intersect. For best results, the star should be located within ± 30 minutes in R.A. of the meridian
and within ± 5’ of the celestial equator.
3. Note the extent of the star’s drift in Declination (disregard drift in Right Ascension):
a. If the star drifts South , the telescope’s polar axis is pointing too far East.
b. If the star drifts North, the telescope’s polar axis is pointing too far West.
4. Carefully move the table tripod of the Model 2045 to effect the appropriate change in polar alignment.
Reposition the telescope’s East-West polar axis orientation until there is no further North-South
drift by the star. Track the star for a period of time to be certain that its Declination drift has
ceased.
5. Next, point the telescope at another moderately bright star near the Eastern horizon, but still
near the celestial equator. For best results, the star should be about 20° or 30‘ above the
Eastern horizon and within ± 5' of the celestial equator.
6. Again note the extent of the star’s drift in Declination:
a. If the star drifts South, the telescope’s polar axis is pointing too low.
b. If the star drifts North , the telescope’s polar axis is pointing too high .
7. Change the extension length of the adjustable tripod leg to effect the appropriate corrections in
latitude angle. Again track the star for a period of time to be certain that Declination drift has ceased.
The above procedure results in very accurate polar alignment, and minimizes the need for tracking
corrections during astrophotography.
The optional Meade Equatorial Wedge/Field tripod system provides an extremely stable platform for the
most discriminating long exposure photography and also permits standing observations through the
telescope in the equatorial mode.
ELECTRONIC MOTOR DRIVE
Supplied as standard equipment with the Model 2045 is an extremely accurate drive gear drive system,
driven by a precision pulse motor. The power cord from the battery pack plugs into the bottom of the
telescope’s drive base. The North-South switch, located on the bottom plate of the drive base (see (4),
Fig. 1), reverses the motor drive direction, thus permitting use of the telescope in both the Northern and
Southern hemispheres.
With the telescope set up in the equatorial mode (as described above under "Lining Up with the Pole"),
plug the power cord into the drive base. Immediately, if you put your ear to the drive base of the
telescope, you will be able to hear the low level noise created by the running motor. The drive system
turns the fork mount of the telescope through one complete revolution every 24 hours, and results in the
stars "standing still" as you view them through the telescope eyepiece. The motor drive also drives the
R.A. setting circle, (see (8) Fig. 1), as described in the next section.
The motion of the telescope caused by the drive system is not obvious if you look at the telescope (in fact,
it is not even perceptible). However, while observing through the telescope, it is a very significant motion
indeed. To check this point, with a star centered in the telescope field and the electric motor drive
running, unplug the power cord: the star will immediately begin to drift out of the field of view; at higher
powers, the effect is even more pronounced.
The motor drive is engaged by turning the R.A. lock (see (7), Fig. 1) to the locked position. Simply
"unlock" the R.A. lock to disengage the motor drive when manually pointing the telescope at another
object.
in