Meade 102ACHR/500 Bedienungsanleitung

Andere Handbücher für 102ACHR/500

1

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INSTRUCTION

MANUAL

Meade*

Model

102ACHR/500

4"

Achromatic

Refracting

Telescope

Meade

Instruments

Corporation

ii*

WARNING!

Never

use

the

Meade

Model

102ACHR/500

Telescope

to

look

at

the

Sun

!

Observing

the

Sun,

even

for

the

shortest

fraction

of

a

second,

will

cause

instant

and

irreversible

damage

to

your

eye

as

well

as

physical

damage

to

the

telescope

itself.

When

observing

with

the

telescope

during

the

daytime,

do

not

point

the

telescope

even

close

to

the

Sun.

Fig.

1:

The

Meade

Model

102ACHR/500

Refracting

Telescope

-

3

Captions

for

Fig.

1

1.

Cradle

Rings

2.

Viewfinder

3.

Focuser

Lock

Knob

4.

Eyepiece

5.

Diagonal

Prism

6.

Focus

Knob

7.

Declination

(Dec)

Slow

Motion

Control

8.

Right

Ascension

(R.A.)

Setting

Circle

9.

Dust

Cover

for

Optional

#812

Polar

Alignment

Finder

10.

Latitude

Scale

11.

Fine

Latitude

Adjustment

Knob

12.

Tripod

Legs

13.

Tripod

Head

14.

Fine

Azimuth

Adjustment

Knob

15.

Counterweight

Safety

Stop

16.

Counterweight

Rod

17.

7.5

lb

(3.4

kg)

Counterweights

18.

Counterweight

Cone

19.

Polar

Axis

20.

Dec

Setting

Circle

21.

Dec

Lock

Lever

22.

Cradle

Ring

Knobs

23.

Objective

Lens

Cell

24.

Dew

Shield

Safety

Screw

25.

Dew

Shield

26.

Latitude

Angle

(Elevation

Angle)

of

the

Polar-Aligned

Telescope

27.

Declination

Axis

28.

Counterweight

Lock

Screws

29.

Cradle

Ring

Lock

Knobs

CAUTION!

The

Meade

Model

102ACHR/500

telescope

is

a

serious

astronomical

instrument.

Because

of

the

significant

weight

of

the

telescope,

children

should

not

be

allowed

to

play

near

the

telescope

at

any

time.

Parents

should

use

caution

and

common

sense

when

allowing

children

to

observe

through

the

telescope.

Technical

Note:

The

Model

102ACHR/500

may

be

supplied

in

either

of

two

versions:

with

either

the

Meade

LXD

500A

Equatorial

Mount

(with

aluminum

gears)

or

the

LXD

500B

Equatorial

Mount

(with

bronze

gears).

Set

up

and

operation

of

the

telescope

are

identical

in

either

case.

®

The

name

'Meade'

and

the

Meade

logo

are

trademarks

registered

with

the

U.S.

Patent

Office

and

in

principal

countries

throughout

the

world.

Contents

Model

102ACHR/500

4"

Achromatic

Refractor

Introduction.4

Parts

Listing

and

Assembly.4

Preparing

the

LXD

500

Tripod.4

Setting

Up

the

tripod.4

Attaching

the

Accessory

Tray.4

Varying

the

Tripod

Height.4

Collapsing

the

Tripod.4

Assembly

of

the

Equatorial

Mount.4

Attaching

the

Equatorial

Head

to

the

Tripod.5

Attaching

the

Counterweights.5

Slow

Motion

Control

Knobs.5

Mounting

the

Cradle

Rings.5

Mounting

the

Optical

Tube

Assembly.6

Attaching

the

Diagonal

Prism

and

Eyepiece.6

Mounting

the

Viewfinder.6

Balancing

the

Telescope.

6

First

Observations.7

Telescope

Controls

7

The

Viewfinder.7

Focusing

the

Viewfinder.7

Alignment

of

the

Viewfinder.7

Using

the

Viewfinder.8

Magnification.8

Astronomical

Observing.8

Celestial

Coordinates:

Declination

&

Right

Ascension

.

.

8

Polar

Alignment.9

Polar

Alignment

Procedures.9

Using

a

Polar

Aligned

Telescope.10

Locating

Astronomical

Objects.10

Precise

Polar

Alignment

Procedures.10

Setting

Circles.10

Observing

Tips.10

Terrestrial

Observing.11

image

Orientation.11

Optional

Accessories.11

Telescope

Maintenance

and

Servicing.12

General

Maintenance

Guidelines.12

Proper

Storage

and

Transport

of

the

Telescope.13

Meade

Customer

Service.13

Specifications.14

1998

Meade

Instruments

Corporation

-

4

■

MODEL

102ACHR/500

4"

ACHROMATIC

REFRACTOR:

INTRODUCTION

The

Meade

Model

102ACHR/500

Telescope

is

ideally

suited

to

the

serious

beginning

or

intermediate

amateur

astronomer

or

terrestrial

observer.

With

its

2-element,

4"

achromatic

objective

lens,

observers

can

view

craters

and

fault

lines

on

the

Moon;

cloud

features

on

the

planet

Jupiter

and

Jupiter's

four

largest

moons,

as

well

as

the

rings

of

Saturn

and

Saturn’s

largest

moon.

Titan,

Beyond

the

Solar

System,

the

Model

102ACHR/500

telescope

permits

detailed

observations

of

nebulae,

star

clusters,

galaxies,

and

other

deep-space

objects.

For

optimal

enjoyment

of

the

Meade

Model

102ACHR/500

telescope,

please

take

a

few

minutes

to

read

this

manual

thoroughly

and

become

familiar

with

all

of

the

instrument's

astronomical

and

terrestrial

observing

capabilities.

PARTS

LISTING

AND

ASSEMBLY

When

opening

the

two

packing

boxes

for

the

first

time,

note

carefully

the

following

parts

included

with

the

Model

102ACHR/500

telescope:

Box

1:

■

Optical

Tube

Assembly,

with-cradle

rings

attached.

■

Accessories,

packed

with

the

optical

tube

assembly:

—

Plossl

(PL)

25mm

eyepiece

—

#918A

diagonal

prism

-

6

x

30mm

viewfinder

and

bracket

r-ig.

2

XT-

100

Tripod.

(1)

Azimuth

Tangent

Arm;

(2)

Tripod

Head;

i

*

-nmon

strut:

(4)

Accessory

Tray;

(5)

Height

Adjustment

Box

2:

■

LXD

500

Equatorial

Mount,

including:

—

Tripod

—

Equatorial

head

—

Lock

knob

with

twist

bar

(Fig.

4)

—

2

washers

(1

large

and

1

small

washer

for

lock

knob

with

twist

bar)

—

Counterweight

rod

with

gray

counterweight

cone

—

2

pcs.

7.5

lb

(3.4

kg)

counterweights

—

2

slow

motion

control

knobs

—

Accessory

tray

To

assemble

the

telescope,

follow

these

steps:

1.

Preparing

the

LXD

500

tripod

The

LXD

500

tripod

(Fig.

2)

is

shipped

virtually

completely

assembled

from

the

factory.

Once

set

up,

all

that

is

required

of

an

observer

is

to

attach

the

accessory

tray

and

adjust

the

tripod

to

the

desired

observing

height.

a.

Setting

Up

the

Tripod:

Remove

the

tripod

from

the

shipping

box

and

stand

the

tripod

vertically

with

the

tripod

feet

down.

Grasp

two

of

the

tripod

legs

and

with

the

full

weight

of

the

tripod

on

the

third

leg,

gently

pull

the

legs

apart

to

the

fully

open

position

(Fig.

2).

b.

Attaching

the

Accessory

Tray:

Remove

the

round

accessory

tray

(4),

Fig.

2.

from

the

shipping

box.

Unthread

the

black,

star-shaped

lock

knob

from

the

bottom

of

the

tray.

Place

the

threaded

rod

on

the

underside

of

the

accessory

tray

through

the

central

hub

of

the

extension

strut.

Rethread

the

lock

knob

onto

the

accessory

tray.

c.

Varying

the

Tripod

Height:

Loosen

the

black,

star-shaped

height

adjustment

knob

(5),

Fig.

2,

at

the

base

of

each

tripod

leg.

Slide

the

three

inner

tripod

leg

sections

out

to

the

desired

height.

Firmly

tighten

(but

do

not

overtighten)

the

three

height

adjustment

knobs

(5),

Fig.

2.

d.

Collapsing

the

Tripod:

Remove

the

accessory

tray

(4),

Fig.

2.

Grasp

the

tripod

head

(2),

Fig.

2,

with

one

hand.

With

the

other

hand,

pull

directly

up

on

the

central

hub

of

the

extension

strut,

where

the

accessory

tray

(4),

Fig,

2,

was

attached.

This

action

will

cause

the

tripod

legs

to

move

inward

to

a

collapsed

position.

Important

Notes

on

the

LXD

500

Tripod:

•

Remove

the

accessory

tray

before

attempting

to

collapse

the

tripod.

•

If

the

tripod

does

not

extend

or

collapse

easily,

do

not

force

the

tripod

legs

in

or

out.

By

following

the

above

instructions,

the

tripod

will

function

properly.

Forcing

the

tripod

into

an

incorrect

position

may

damage

the

extension

strut

system.

•

Do

not

overtighten

the

three

star-shaped

height

adjustment

knobs

on

the

tripod

legs.

“Firm

feel”

tightening

is

sufficient.

2.

Assembly

of

the

Equatorial

Mount

All

the

parts

required

for

the

Equatorial

Mount

can

be

found

(with

the

tripod)

in

the

LXD

500

Mount

shipping

box.

The

Optical

Tube

Assembly

(OTA)

is

shipped

in

a

separate

box.

To

assemble

the

mount,

follow

these

instructions:

Fig.

3:

Attaching

the

Equatorial

Head

to

Tripod.

(1)

Fine

Azimuth

Adjustment

Knobs;

(2)

Azimuth

Tangent

Arm;

(3)

North

Facing

Tripod

Leg;

(4)

Tripod

Head;

(5)

Equatorial

Head.

a.

Attaching

the

Equatorial

Head

to

the

Tripod:

On

the

Equatorial

Head

(5),

Fig.

3,

loosen

the

two

Fine

Azimuth

Adjustment

Knobs

(1),

Fig.

3,

to

create

a

space

between

the

two

knobs

(as

seen

from

the

underside

of

the

Equatorial

Head).

The

Azimuth

Tangent

Arm

(2),

Fig.

3,

fits

between

these

two

threaded

knobs.

Unthread

and

remove

the

lock

knob

with

twist

bar,

Fig.

4,

and

two

washers

from

the

base

of

the

Equatorial

Head

(5),

Fig.

3.

Place

the

Equatorial

Head

on

the

Tripod

Head

(4),

Fig.

3,

aligning

it

so

that

the

Azimuth

Tangent

Arm

(2),

Fig.

3,

slips

between

the

two

Fine

Azimuth

Adjustment

Knobs

(1),

Fig.

3.

With

the

Equatorial

Head

(5),

Fig.

3,

sitting

flat

on

the

Tripod

Head

(4),

Fig.

3,

place

the

small

washer,

then

the

large

washer

over

the

threads

of

the

lock

knob

with

twist

bar,

Fig.

4,

and,

from

the

underside

of

the

Tripod

Head,

thread

the

lock

knob

with

twist

bar

(and

washers)

through

the

Tripod

Head

and

into

the

base

of

the

Equatorial

Head.

Tighten

firmly

but

do

not

overtighten.

Simultaneously

tighten

both

of

the

Fine

Azimuth

Adjustment

Knobs

(1).

Fig.

3.

Each

knob

will

press

against

the

Azimuth

Tangent

Arm

(2),

Fig.

3.

Do

not

overtighten.

b

Attaching

the

Counterweights:

On

the

counterweight

rod

(3),

Fig.

5,

confirm

that

the

gray

counterweight

cone

(2),

Fig.

5,

is

threaded

onto

the

rod

as

far

as

possible.

Then,

thread

the

counterweight

rod,

with

the

counterweight

cone

in

place,

into

the

bottom

of

the

decimation

housing

(1),

Fig.

5.

When

the

counterweight

Fig.

5:

Installing

Counterweight

Rod.

(1)

Declination

Housing;

(2)

Counterweight

Cone;

(3)

Counterweight

Rod;

(4)

R.A.

Slow

Motion

Control

Shaft;

(5)

R.A.

Lock

Lever;

(6)

Dec

Slow-Motion

Control

Shaft

(on

opposite

side);

(7)

Saddle

Plate.

rod

is

threaded

in

as

far

as

possible,

additionally

secure

the

rod

by

turning

the

gray

counterweight

cone

(2),

Fig.

5,

clockwise

until

tight.

At

the

end

of

the

counterweight

rod

(3),

Fig.

5,

unscrew

the

counterweight

safety

stop

(15),

Fig.

1.

Slide

each

counterweight

onto

the

rod

and

lock

in

place

by

tightening

its

black

counterweight

lock

screw

(28),

Fig.

1.

As

soon

as

the

second

counterweight

is

secure,

replace

the

counterweight

safety

stop.

Be

certain

that

the

counterweight

safety

stop

is

always

securely

in

place.

c.

Slow

Motion

Control

Knobs:

There

are

two

identical

slow

motion

control

knobs.

See

(2)

and

(4),

Fig.

7.

Attach

one

of

these

knobs

to

the

R.A.

Slow

Motion

Control

Shaft

(4),

Fig.

5,

by

aligning

the

knob

so

that

its

knurled

thumb

screw

will

slide

directly

over

the

flat

area

on

the

R.A.

Slow

Motion

Control

Shaft.

Tighten

the

knurled

thumb

screw

to

a

firm

feel.

Do

not

overtighten.

Attach

the

second

knob

to

the

Dec

Slow

Motion

Control

Shaft

(6),

Fig.

5,

by

aligning

the

knob

so

that

its

knurled

thumb

screw

will

slide

directly

over

the

flat

area

on

the

Dec

Slow

Motion

Control

Shaft.

Tighten

the

knurled

thumb

screw

to

a

firm

feel.

Do

not

overtighten.

d.

Mounting

the

Cradle

Rings:

The

Optical

Tube

Assembly

.(OTA)

is

shipped

from

the

factory

with

the

cradle

rings

(1),

Fig.

1,

secure

around

the

tube.

To

remove

the

cradle

rings

from

the

OTA,

loosen

each

cradle

ring

knob

(22),

Fig.

1.

The

cradle

rings

are

hinged

so

they

can

be

opened

by

lifting

the

top

portion

of

the

ring.

Unthread

and

remove

the

cradle

ring

lock

knob

(29),

Fig.

1,

found

at

the

base

of

each

cradle

ring

(1),

Fig.

1.

Align

the

base

of

each

cradle

ring

with

a

mounting

hole

on

the

saddle

plate

(7).

Fig.

5,

and

thread

a

lock

knob

up

through

the

saddle

plate

into

each

cradle

ring.

Tighten

to

a

firm

feel.

-

6

-

Note:

The

cradle

rings

may

be

attached

with

the

cradle

ring

knobs

on

either

the

left

or

right

side

of

the

equatorial

head,

as

long

as

both

hinges

open

in

the

same

direction.

e.

M

ounting

the

Optical

Tube

Assembly:

Before

placing

the

OTA

in

the

cradle

ring

assembly,

confirm

that

the

counterweights

are

attached

to

the

mount

and

the

R.A.

lock

lever

(3),

Fig.

7,

and

the

Dec

lock

lever

(1),

Fig.

7,

are

firmly

locked

by

rotating

each

lever

clockwise

until

it

stops.

With

both

cradle

rings

open,

place

the

OTA

into

the

cradle

ring

assembly.

With

one

hand

holding

the

OTA

in

place,

close

the

cradle

rings.

Tighten

the

two

cradle

ring

knobs

to

a

firm

feel.

Do

not

overtighten.

Located

at

the

end

of

the

OTA

is

the

Dew

Shield

(25),

Fig.

1,

which

can

be

removed

when

.cleaning

the

objective

lens

(See

General

Maintenance

Guidelines,

page

12.)

Care

should

be

taken

when

replacing

the

Dew

Shield

to

tighten

the

Dew

Shield

Safety

Screw

(24),

Fig.

1.

Tightening

of

the

safety

screw

will

prevent

accidental

dislodgment

of

the

Dew

Shield

during

an

observing

session

Fig.

6:

Attaching

the

Diagonal

Prism

and

Eyepiece.

(1)

Alignment

Screws;

(2)

Viewfinder;

(3)

Focus

Lock

Knob;

(4)

Eyepiece:

(5)

Diagonal

Prism;

(6)

Focuser

Drawtube;

(7)

Focus

Knob;

(8)

Viewfinder

Mount

f.

A

ttaching

the

Diagonal

Prism

and

Eyepiece:

Slide

the

diagonal

prism

(5),

Fig.

6,

directly

into

the

focuser

drawtube

(6)

Fig.

6,

of

the

telescope

and

lock

in

place

by

turning

its

thumbscrew

clockwise

until

tight

(firm-feel

only).

Insert

the

provided

PL

25mm

eyepiece

(4),

Fig.

6,

into

the

diagonal

prism

and

lock

in

place

by

tightening

the

thumbscrew.

Do

not

overtighten

the

thumbscrews.

Note

For

astronomical

observations,

the

diagonal

prism

generally

provides

a

comfortable

right-angle

viewing

position.

Alternately

.

an

eyepiece

may

be

inserted

directly

into

the

rear

ceii

for

straight-through

observations.

With

the

diagonal

prism

in

place,

images

will

be

right-side-up

but

reversed

left-for-right.

With

the

eyepiece

inserted

directly

into

the

rear

cell

(straight

through),

images

will

be

upside-down.

For

astronomical

purposes,

the

image

orientation

is

usually

of

no

importance.

For

■

errestnal

observations,

where

a

fully

corrected

image

is

highly

desiraole.

the

optional

Meade

#928

45°

Erect-Image

Diagonal

Pnsni

should

be

ordered

separately.

(See

Optional

Accessories,

page

12.)

g.

M

ounting

the

Viewfinder;

The

viewfinder,

bracket

and

mounting

hardware

are

shipped

in

the

box

with

the

optical

tube

assembly.

Between

the

focus

lock

knob

(3),

Fig.

6,

and

the

optical

tube,

locate

the

four

machine

screws,

Fig

6A,

threaded

into

holes

on

the

flat,

viewfinder

mounting

area.

Remove

the

four

machine

screws.

Align

the

two

holes

and

the

two

open

slots

on

the

base

of

the

viewfinder

mount

(8).

Fig.

6,

with

the

threaded

holes

on

the

viewfinder

mounting

area.

Thread

the

four

screws

through

the

viewfinder

mount

into

the

telescope.

Tighten

to

a

firm

feel,

but

do

not

overtighten.

Alignment

of

the

viewfinder

is

discussed

later

in

this

manual.

BALANCING

THE

TELESCOPE

The

telescope

must

be

balanced

around

both

axes.

With

an

improperly

balanced

telescope,

objects

may

become

difficult

to

find

or,

once

found,

may

be

easily

lost.

To

balance

the

telescope:

1.

Loosen

the

R.A.

lock

lever

(3),

Fig.

7,

by

rotating

the

lever

counterclockwise

until

it

stops.

The

Optical

Tube

Assembly

now

rotates

freely

about

the

Polar

Axis

(19),

Fig.

1.

Rotate

the

telescope

so

that

the

counterweight

rod

is

parallel

to

the

ground

(horizontal).

2.

Loosen

the

counterweight

lock

screws

(28),

Fig.

1,

and

slide

the

counterweights

along

the

rod

until

the

telescope

remains

in

one

position

without

tending

to

drift

in

either

direction.

Re-tighten

the

counterweight

lock

screws

and

the

R.A.

lock

lever.

3.

Loosen

the

Dec

lock

lever

(1),

Fig.

7,

by

rotating

the

lever

counterclockwise

until

it

stops.

The

Optical

Tube

Assembly

now

rotates

freely

about

the

Declination

Axis

(27),

Fig,

1.

Rotate

the

optical

tube

assembly

so

that

the

tube

is

parallel

to

the

ground

(horizontal).

4.

Slightly

loosen

the

two

cradle

ring

knobs

(22),

Fig.

1.

5.

Slide

the

tube

back

and

forth

within

the

cradle

rings

until

the

telescope

is

in

balance

about

the

Declination

Axis.

Tighten

the

cradle

ring

knobs

and

the

Dec

lock

lever

when

balanced.

With

the

telescope

properly

balanced,

it

is

possible

to

place

the

optical

tube

in

any

position

without

drifting.

Rebalancing

may

be

necessary

with

the

addition

of

any

optional

accessories.

Fig.

7:

Telescope

Controls.

(1)

Dec

Lock

Lever;

(2)

R.A.

Slow-

Motion

Control;

(3)

R.A.

Lock

Lever;

(4)

Dec

Slow-Motion

Control.

Fig.

8:

Viewfinder.

(1)

Viewfinder

Eyepiece;

(2)

Rear

Alignment

Screws;

(3)

Mounting

Bracket;

(4)

Front

Alignment

Screws;

(5)

Focus

Lock

Ring;

(6)

Objective

Lens

Cell.

FIRST

OBSERVATIONS

Remove

the

dust

cover

from

the

objective

lens

by

gently

twisting

the

cover

and

pulling

It

away

from

the

objective

lens.

Telescope

Controls

An

important

array

of

controls

facilitates

operation

of

the

Model

102ACHR/500

telescope.

It

is

best

to

become

familiar

with

all

of

these

controls

before

attempting

observations

through

the

telescope.

Focus

Knobs

(7),

Fig.

6:

Turning

these

knobs

moves

the

eyepiece

closer

to

or

farther

away

from

the

objective

lens,

thereby

changing

the

focus.

The

telescope

can

be

focused

on

objects

from

a

distance

of

about

50

feet

to

infinity.

Focus

Lock

Knob

(3),

Fig.

6:

The

focus

lock

knob

is

designed

to

prevent

the

focuser

drawtube

(6),

Fig.

6,

from

moving

when

heavy

accessories

(e.g.,

a

camera

body)

are

attached

to

the

focuser

assembly.

For

normal

observing,

with

an

eyepiece

and

diagonal

mirror,

it

is

not

necessary

to

utilize

the

lock

knob.

Dec

Lock

Lever

(1),

Fig.

7:

Locking

and

unlocking

the

Declination

movement

of

the

optical

tube

is

accomplished

by

moving

the

Dec

lock

lever

clockwise

until

it

stops

for

the

fully

locked

position,

or

by

moving

the

Dec

lock

lever

counterclockwise

to

the

fully

unlocked

position.

Dec

Slow-Motion

Control

(4),

Fig.

7:

With

the

Dec

lock

lever

in

the

fully

locked

position,

the

Dec

Slow-Motion

Control

may

be

used

for

fine

motions

of

the

telescope

in

Declination.

(The

meaning

of

''Dec,"

or

Declination,

is

explained

later

in

the

manual.)

R.A.

Lock

Lever

(3),

Fig.

7:

Locking

and

unlocking

the

Right

Ascension

movement

is

accomplished

by

rotating

the

R.A.

lock

lever

clockwise

until

it

stops

for

the

fully

locked

position

and

counterclockwise

for

the

fully

unlocked

position.

R.A.

Slow-Motion

Control

(2),

Fig.

7:

With

the

R.A.

lock

lever

fully

locked,

the

R.A.

Slow-Motion

Control

permits

manual

slow-

motion

of

the

telescope

in

Right

Ascension.

(The

meaning

of

"R.A.,”

or

Right

Ascension,

is

explained

later

in

the

manual.)

After

becoming

familiar

with

the

telescope’s

controls,

make

your

first

observations

of

a

simple

land

object

—

a

telephone

pole

or

building,

perhaps,

several

hundred

yards

in

the

distance.

Keep

in

mind

that

the

viewfinder

has

not

been

aligned,

so

it

will

be

necessary

to

sight

along

the

optical

tube

to

“aim"

the

telescope

at

the

object.

With

the

PL

25mm

eyepiece

in

place,

unlock

the

R.A,

and

Dec

lock

levers.

The

telescope

now

turns

freely

on

both

axes,

permitting

the

location

of

objects

in

the

telescope.

With

an

object

roughly

centered

in

the

telescopic

field,

as

viewed

through

the

eyepiece,

retighten

the

R.A.

and

Dec

lock

levers.

While

looking

through

the

eyepiece,

turn

the

focus

knob

clockwise

or

counterclockwise

until

the

object

is

in

focus.

Note:

With

the

eyepiece

inserted

directly

into

the

rear

cell

of

the

telescope,

without

using

the

diagonal

prism,

the

image

through

the

eyepiece

will

be

inverted

and

reversed

left-for-right.

The

inverted

image

is

a

result

of

the

optical

structure

of

the

telescope

and

is

normal

for

astronomical

telescopes.

If

the

diagonal

prism

is

inserted

into

the

telescope

first,

then

the

eyepiece,

the

image

appears

right-side-up,

but

still

reversed

left-for-right.

Once

the

selected

object

is

in

focus,

with

the

R.A.

lock

lever

and

Dec

lock

lever

LOCKED,

use

the

R.A.

Slow-Motion

Control

and

the

Dec

Slow-Motion

Control

to

center

the

object

in

the

field

of

view,

THE

VIEWFINDER

The

Model

102ACHR/500

telescope,

as

with

almost

all

astronomical

telescopes,

presents

a

fairly

narrow

field

of

view

to

the

observer.

As

a

result,

it

is

sometimes

difficult

to

locate

and

center

objects

in

the

telescope.

The

viewfinder,

by

contrast,

is

a

low-power,

wide-field

sighting

scope

with

crosshairs

that

enable

the

easy

centering

of

objects

in

the

main

telescope’s

field

of

view.

Standard

equipment

with

the

Model

102ACHR/500

telescope

is

a

viewfinder

of

6-power

and

30mm

aperture,

called

a

“6

x

30mm

viewfinder.”.

1.

Focusing

the

Viewfinder

The

viewfinder

has

been

factory

prefocused

to

objects

located

at

infinity.

Individual

eye

variations,

however,

may

require

that

the

viewfinder

be

refocused

to

your

eye.

Looking

through

the

viewfinder,

point

the

telescope

at

a

distant

object;

if

the

viewfinder

image

is

not

sufficiently

in

focus

for

your

eye,

it

may

be

refocused

as

follows:

a.

Remove

the

viewfinder

from

its

mounting

bracket

(3),

Fig.

8,

by

slightly

unthreading

the

six

alignment

screws

(2)

and

(4),

Fig.

8,

until

the

viewfinder

can

slip

out

easily.

b.

Loosen

the

focus

lock

ring

(5),

Fig,

8.

thereby

enabling

rotation

of

the

viewfinder's

objective

lens

cell

(6),

Fig.

8.

While

looking

at

a

distant

object

through

the

viewfinder,

rotate

the

objective

lens

cell

clockwise

or

counterclockwise

until

sharp

focus

is

achieved.

c.

Tighten

the

focus

lock

ring

(5),

Fig.

8,

to

lock

the

focus

in

place.

d.

Replace

the

viewfinder

into

its

bracket

(3),

Fig.

8,

on

the

main

telescope.

Note:

No

focusing

is

possible

(or

required)

from

the

eyepiece

end

of

the

viewfinder.

2.

Alignment

of

the

Viewfinder

In

order

for

the

viewfinder

to

be

useful,

it

must

first

be

aligned

with

the

main

telescope,

so

that

both

the

viewfinder

and

the

main

telescope

are

pointing

at

precisely

the

same

place.

To

align

the

viewfinder,

follow

this

procedure:

a.

The

viewfinder

bracket

includes

six

alignment

screws.

Turn

the

three

rear

alignment

screws

(2).

Fig,

8,

roughly

centering

the

viewfinder

within

its

bracket

(as

viewed

from

the

eyepiece-end

of

the

telescope).

When

centered,

tighten

the

knurled

lock

nut

on

each

of

the

three

rear

alignment

screws

until

the

lock

nuts

are

flush

against

the

bracket

ring.

b.

Using

the

standard

equipment

PL

25mm

eyepiece,

point

the

main

telescope

at

some

easy-to-locate,

well-defined.

8

but

distant,

land

object,

such

as

the

top

ot

a

telephone

pole.

Center

the

object

precisely

in

the

main

telescope

s

field

and

lock

the

R.A.

lock

lever

and

Dec

lock

lever

so

that

the

telescope

does

not

move

away

from

the

object.

c.

While

looking

through

the

viewfinder,

turn

one

or

more

of

the

three

front

viewfinder

alignment

screws

(4),

Fig.

8.

until

the

crosshairs

of

the

viewfinder

point

at

precisely

the

same

position

as

the

main

telescope.

Tighten

the

knurled

lock

nut

on

each

of

the

front

alignment

screws

until

the

lock

nuts

are

flush

against

the

bracket

ring.

The

viewfinder

is

now

aligned

with

the

main

telescope.

Unless

the

alignment

screws

are

disturbed,

the

viewfinder

will

remain

aligned

indefinitely.

3.

Using

the

Viewfinder

Now,

to

locate

any

object,

terrestrial

or

astronomical,

first

center

the

object

on

the

crosshairs

of

the

viewfinder;

the

object

will

then

be

centered

in

the

field

of

the

main

telescope.

Note:

If

higher

observing

magnifications

are

desired,

first

locate,

center,

and

focus

the

object

using

a

low-power

eyepiece

(e.g..

the

PL

25mm

eyepiece).

Objects

are

easier

to

locate

and

center

at

low

powers:

higher

powers

may

then

be

employed

by

changing

eyepieces.

MAGNIFICATION

The

magnification,

or

power,

at

which

a

telescope

is

operating

is

determined

by

two

factors:

the

focal

length

of

the

eyepiece

employed

and

the

focal

length

of

the

telescope.

The

Model

102ACHR/500

telescope

is

supplied

with

one

eyepiece

as

standard

equipment.

The

focal

length

of

the

eyepiece,

25mm,

is

printed

on

its

side.

Telescope

focal

length

is,

roughly

speaking,

the

distance

that

light

travels

inside

the

telescope

before

reaching

a

focus.

The

focal

length

of

the

Model

102ACHR/500

telescope

is

920mm

On

a

given

telescope,

different

eyepiece

focal

lengths

are

used

to

achieve

different

magnifications,

from

low

to

high.

Optional

eyepieces

and

the

Series

4000

#140

2x

Barlow

Lens

are

available

for

powers

from

a

range

of

about

25x

to

400x.

depending

on

the

focal

length

of

the

telescope

and

eyepiece

(see

OPTIONAL

ACCESSORIES,

page

11).

To

calculate

the

magnification

(or

power)

obtained

with

a

given

eyepiece,

use

this

formula:

Telescope

Focal

Lengthy

Power

-

Ey

e

pj

ece

Focal

Length

Example:

Using

the

PL

25mm

eyepiece

supplied

with

the

Model

102ACHR/500

telescope,

the

power

is:

Power

920mm

25mm

=

37x

ASTRONOMICAL

OBSERVING

Understanding

how

and

where

to

locate

celestial

objects,

and

how

those

objects

move

across

the

sky

is

fundamental

to

enjoying

the

hobby

of

astronomy.

This

section

provides

a

basic

introduction

to

the

terminology

associated

with

astronomy,

and

includes

instructions

for

finding

and

tracking

celestial

objects.

Celestial

Coordinates:

Declination

and

Right

Ascension

Celestial

objects

are

mapped

according

to

a

coordinate

system

on

the

Celestial

Sphere,

the

imaginary

sphere

on

which

all

stars

appear

to

be

placed.

This

celestial

object

mapping

system

is

analogous

to

the

Earth-based

coordinate

system

of

latitude

and

longitude.

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.

This

point

in

the

sky

is

located

near

the

North

Star,

Polaris.

The

faint

star

Sigma

Octans

lies

near

the

South

Celestial

Pole,

where

the

extension

of

Earth's

axis

through

the

South

Pole

intersects

the

celestial

sphere.

In

mapping

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

a

projection

of

the

Earth's

Equator

onto

the

celestial

sphere.

In

mapping

the

celestial

sphere,

just

as

on

the

surface

of

the

Earth,

imaginary

lines

have

been

drawn

to

form

a

coordinate

grid.

Thus,

object

positions

on

the

Earth's

surface

are

specified

by

their

latitude

and

longitude.

For

example,

you

could

locate

Los

Angeles,

California,

by

its

latitude

(34°)

and

longitude

(118°);

similarly,

you

could

locate

the

constellation

Ursa

Major

by

its

position

on

the

celestial

sphere:

The

most

common

mistake

of

the

beginning

observer

is

to

“overpower”

the

telescope

and

use

high

magnifications

which

the

telescope’s

aperture

and

typical

atmospheric

conditions

cannot

reasonably

support.

Keep

in

mind

that

a

smaller

but

bright

and

well-resolved

image

is

far

superior

to

a

larger

but

dim

and

poorly

resolved

one.

Powers

above

about

200x

should

be

employed

only

under

the

steadiest

atmospheric

conditions.

Most

observers

will

want

to

have

3

or

4

eyepieces

and

perhaps

the

Series

4000

#140

2x

Barlow

Lens

to

achieve

the

full

range

of

reasonable

magnifications.

See

OPTIONAL

ACCES¬

SORIES,

page

11,

for

further

details.

R.A.:

11

hr;

Dec:+50°.

The

celestial

analog

to

Earth

latitude

is

called

Declination,

or

“Dec'\

and

is

measured

in

degrees,

minutes

and

seconds

(e.g..

15"

27'

33").

Declination

north

of

the

celestial

equator

is

indicated

with

a

“+”

sign

in

front

of

the

measurement

(e.g..

the

Declination

of

the

North

Celestial

Pole

is

+90°),

with

Declination

south

of

the

celestial

equator

indicated

with

a

sign

(e

g.,

the

Declination

of

the

South

Celestial

Pole

is

-90°)

(Fig.

9).

Any

point

on

the

celestial

equator

itself

(which,

for

example,

passes

through

the

constellations

Orion,

Virgo

and

Aquarius)

is

specified

as

having

a

Declination

of

zero,

shown

as

0°

O’

0".

-

9

-

The

celestial

analog

to

Earth

longitude

is

called

"Right

Ascension",

or

"R

A

."

and

is

measured

in

time

on

the

24

hour

"clock"

and

shown

in

hours

("hr"),

minutes

("min")

and

seconds

(

sec")

from

an

arbitrarily

defined

"zero"

line

of

Right

Ascension

passing

through

the

constellation

Pegasus.

Right

Ascension

coordinates

range

from

Ohr

Omin

Osec

to

23hr

59min

59sec.

Thus

there

are

24

primary

lines

of

R.A.,

located

at

15

degree

intervals

along

the

celestial

equator.

Objects

located

further

and

further

east

of

the

prime

Right

Ascension

grid

line

(Ohr

Omin

Osec)

carry

increasing

R.A.

coordinates.

All

celestial

objects

are

specified

in

position

by

their

celestial

coordinates

of

Right

Ascension

and

Declination.

The

telescope's

Dec

and

R.A.

setting

circles

(1)

and

(3),

Fig.

10,

may

be

dialed

to

the

coordinates

of

a

specific

celestial

object,

which

may

then

be

located

without

a

visual

search.

However,

before

making

use

of

the

telescope’s

setting

circles

to

locate

celestial

objects,

your

telescope

must

first

be

polar

aligned.

Fig.

10:

R.A.

and

Dec

Controls.

(1)

Dec

Setting

Circle;

(2)

R.A.

Slow-Motion

Control;

(3)

R.A.

Setting

Circle;

(4)

Dec

Slow-Motion

Control.

Polar

Alignment

Celestial

objects

are

essentially

fixed

on

the

Celestial

Sphere.

However,

they

appear

to

move

across

the

sky

in

an

arc

as

the

Earth

rotates

on

its

axis,

with

a

complete

rotation

of

the

Earth

occurring

once

in

every

24

hour

period.

This

apparent

motion

is

not

obvious

to

the

unaided

eye,

but,

when

viewed

through

a

telescope,

this

motion

is

rapid

indeed.

Objects

centered

in

the

telescope

move

entirely

out

of

the

field

of

view

in

15

to

60

seconds,

depending

upon

the

magnification

employed.

During

the

24

hour

period

of

the

Earth's

rotation,

stars

make

one

complete

revolution

about

the

Celestial

Pole,

making

concentric

circles

with

the

Celestial

Pole

at

the

center.

By

lining

up

the

telescope’s

polar

axis

(19),

Fig.

1,

with

the

North

Celestial

Pole

(or

South

Celestial

Pole

if

observing

from

the

Earth's

southern

hemisphere),

celestial

objects

may

be

followed

(tracked)

by

moving

the

telescope

about

only

one

axis,

the

polar

axis.

In

addition,

by

polar

aligning

the

telescope,

the

telescope's

Dec

and

R.A.

setting

circles

(1)

and

(3),

Fig.

10,

may

be

used

to

locate

faint

celestial

objects

directly

from

their

catalogued

coordinates.

Polar

Alignment

Procedures:

Polar

alignment

consists

of

the

following

two

operations

1.

Pick

up

the

entire

telescope-and-tripod

and

orient

the

tripod

so

t

hat

the

leg

directly

beneath

the

counterweights

(the

leg

marked

"N")

points

due

north

.

For

observers

in

the

southern

hemisphere,

pick

up

the

entire

telescope-and-tripod

and

orient

the

tripod

sojhat

the

le

g

directly

beneath

the

counterweights

(the

leg

marked

"N"t

points

due

south

.

2.

Determine

the

latitude

of

your

observing

location

by

checking

a

road

map

or

atlas.

Then,

adjust

the

latitude

of

the

telescope-and-tripod

to

indicate

the

latitude

of

your

observing

location

by

turning

the

fine

latitude

adjustment

knob

(3),

Fig.

11,

clockwise

or

counterclockwise

until

the

latitude

pointer

(1),

Fig.

11,

indicates

the

correct

latitude

on

the

latitude

scale

(6),

Fig.

11.

Fig.

11:

Latitude

Controls.

(1)

Latitude

Pointer;

(2)

Latitude

Lock

Lever

(opposite

side);

(3)

Fine

Latitude

Adjustment

Knob;

(4)

Lock

Nut;

(5)

Latitude

Lock

Knob;

(6)

Latitude

Scale,

It

may

be

necessary

to

loosen

the

lock

nut

(4).

Fig.

11,

to

allow

enough

movement

of

the

mount

to

achieve

the

desired

latitude.

When

the

desired

latitude

has

been

achieved,

tighten

the

lock

nut

until

the

nut

is

flush

against

the

mount.

Step

(1),

above,

is

equivalent

to

pointing

the

telescope's

polar

axis

(19),

Fig.

1,

due

north

(or

due

south

for

observers

in

the

southern

hemisphere).

Step

(2)

is

equivalent

to

making

the

telescope's

latitude

angle

(26),

Fig.

1.

equal

to

the

latitude

angle

of

your

observing

location.

With

(1)

and

(2)

accomplished,

the

telescope

is

sufficiently

well

polar

aligned

for

most

visual

observing

applications.

For

the

majority

of

telescope

applications,

this

procedure

is

entirely

satisfactory.

For

those

interested

in

astrophotography,

or

those

interested

in

utilizing

the

telescope's

setting

circles

to

locate

faint

objects,

a

more

precise

polar

alignment

is

necessary,

requiring

the

optional

#812

Polar

Alignment

Finder

(see

OPTIONAL

ACCESSORIES,

page

11).

Note:

The

Fine

Azimuth

Adjustment

Knobs

(14),

Fig.

1,

are

generally

only

utilized

during

the

precise

polar

alignment

procedure

described

in

the

instructions

accompanying

the

#812

Polar

Alignment

Finder.

Locating

North

by

using

Polaris,

the

North

Star,

is

adequate

for

the

purposes

discussed

above.

Polaris

can

be

found

in

relation

to

the

Big

Dipper

by

projecting

a

line

from

the

so-called

"pointer

stars”

of

the

Big

Dipper

(see

Fig.

12).

For

southern

hemisphere

alignment,

locate

south

by

using

the

faint

star

Sigma

Octans

(the

South

Star).

-11

-

2.

Avoid

setting

up

the

telescope

inside

a

room

and

observing

through

an

open

window

(or,

worse,

a

closed

window!)

In

such

a

case,

air

currents

caused

by

differences

in

indoor/outdoor

temperatures

make

quality

astronomical

optical

performance

impossible.

Note:

A

practical

exception

to

the

above

rule

is

the

case

where

the

telescope

is,

for

example,

set

up

in

a

living

room

or

den

for

observing

an

outdoor

terrestrial

scene

or

view

through

a

closed

window.

At

low

powers

(up

to

about

60x)

the

telescope

will

perform

reasonably

well

in

this

application,

but

the

observer

should

understand

dearly

that

optical

performance

under

these

conditions

cannot

approach

the

performance

that

will

be

realized

if

the

telescope

were

instead

set

up

outside.

3.

As

discussed

above,

avoid

“overpowering”

the

telescope.

If

the

terrestrial

or

astronomical

image

becomes

fuzzy

at

high

powers,

drop

down

to

a

lower

power.

Image

degradation

at

high

powers

is

not

due

to

any

fault

of

the

telescope

but

is

caused

by

heat

waves

and

turbulence

in

the

earth's

atmosphere.

Astronomical

observations

at

high

powers

(i.e.,

above

about

200x)

should

be

undertaken

only

when

the

atmosphere

is

very

steady,

as

confirmed

by

an

absence

of

"twinkling”

in

star

images.

4.

Try

not

to

touch

the

eyepiece

when

observing

through

the

telescope.

Vibrations

in

your

hand

are

immediately

transferred

to

the

telescopic

image.

5.

If

an

observer

wears

eyeglasses

and

does

not

suffer

from

astigmatism,

he

or

she

should

take

off

the

glasses

when

using

the

telescope;

the

telescope's

magnification

compensates

for

near-

or

farsightedness.

Observers

with

astigmatism

should,

however,

wear

their

glasses,

since

the

telescope

cannot

compensate

for

this

eye

defect.

6.

Allow

your

eyes

to

become

“dark

adapted"

before

attempting

serious

astronomical

observations

through

the

telescope.

Night

adaptation

normally

requires

about

10

to

15

minutes.

7.

As

you

use

your

telescope

more

and

more

for

astronomical

observing,

you

will

find

that

you

are

seeing

finer

and

finer

detail

—

on

the

surface

of

Jupiter,

for

example.

Observing

through

a

fine

optical

instrument

is,

to

some

degree,

an

acquired

skill.

Celestial

observing

becomes

increasingly

rewarding

as

your

eye

becomes

better

trained

in

the

detection

of

subtle

variations

of

color,

contrast,

and

resolution.

TERRESTRIAL

OBSERVING

Although

principally

designed

for

astronomical

observing,

the

Model

102ACHR/500

telescope

makes

an

excellent

terrestrial

observing

tool.

The

telescope’s

controls

are

utilized

in

the

same

manner

as

for

astronomical

applications,

but

there

are

differences

when

locating

and

observing

terrestrial

subjects

due

to

image

orientation

through

the

telescope.

Image

Orientation

The

viewfinder

presents

an

inverted

image

which

appears

upside-down

and

reversed

lett-for-right.

With

the

standard-

equipment

diagonal

prism

and

PL

25mm

eyepiece

in

place

in

the

main

telescope,

terrestrial

images

appear

right-side-up.

but

reversed

left-for-right.

This

orientation

is

usually

acceptable

tor

terrestrial

observing,

except

in

the

case

of

reading

a

distant

sign

or

automobile

license

plate,

for

example.

Terrestrial

image

orientation

can

be

fully

corrected

with

the

optional

Meade

#928

45°

Erect-Image

Diagonal

Prism

(see

OPTIONAL

ACCESSORIES,

below).

OPTIONAL

ACCESSORIES

A

wide

assortment

of

professional

Meade

accessories

is

available

for

the

Model

102ACHR/500

telescope.

The

premium

quality

of

these

accessories

is

well-suited

to

the

quality

of

the

instrument

itself.

Eyepieces

Meade

Series

4000

Super

Plossl

(SP),

Super

Wide

Angle

(SWA),

and

Ultra

Wide

Angle

(UWA)

Eyepieces,

in

the

standard

American-size

(1.25")

barrel

diameter,

permit

a

range

of

magnifying

powers

with

the

telescope.

Powers

obtained

with

each

eyepiece

are

as

follows:

Eyepiece

Power

SP

6.4mm

144x

SP

9.7mm

95x

SP

12.4mm

74x

SP

15mm

61

x

SP

20mm

46x

SP

26mm

35x

SP

32mm

29x

SP

40mm

23x

SWA

13.8mm

67x

SWA

18mm

51

x

SWA

24.5mm

38x

UWA

4.7mm

196x

UWA

6.7mm

137x

Meade

Super

Plossl

and

Super

Wide

Angle

Eyepieces

are

ideal

for

general-purpose

astronomical

or

terrestrial

observing.

The

typical

Model

102ACHR/500

user

may

wish

to

add

2

or

3

of

these

eyepieces

to

his

or

her

telescope.

An

introductory

selection

might

include

the

SP

9.7mm

and

SP

15mm.

The

more

advanced

observer

will

perhaps

select

the

SP

9.7mm,

SP

12.4mm.

and

SWA

18mm.

The

Super

Wide

Angle

Eyepiece

series

yields

extremely

wide

fields

of

view,

perfect

for

the

examination

of

star

fields,

diffuse

nebulae,

or

for

terrestrial

applications.

Under

very

steady

seeing

conditions

Meade

UWA

4.7mm

and

6.7mm

eyepieces

present

the

widest

fields

of

view

obtainable

at

high

powers

and

are

excellent

eyepieces

for

the

Moon

and

planets.

#140

2x

Barlow

Lens

An

amplifying

lens,

the

Series

4000

#140

2x

Barlow

doubles

the

power

o

any

eyepiece

with

which

it

is

used.

Insert

the

#140

into

the

telescope's

eyepiece-holder

first,

followed

by

the

diagonal

prism

and

eyepiece.

Example:

For

the

Model

102ACHR/500,

the

standard

equipment

PL

25mm

eyepiece

yields

a

power

of

37x:

when

used

in

conjunction

with

the

Series

4000

#140

2x

Barlow

Lens,

this

eyepiece

yields

74x.