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OPERATING

INSTRUCTIONS

Meade

Instruments

Corporation

1675

Toronto

Way,

Costa

Mesa,

California

92626

U.S.A.

(714)556-2291

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

7

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.

9

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