Orion 9895 User manual

INSTRUCTION MANUAL

IN 221 Rev. B 03/09

Orion 80mm f/7.5 ED Refractor

#9895 Optical Tube Assembly

Congratulations on your purchase of an Orion 80mm f/7.5 ED

refractor optical tube. Your 80mm f/7.5 ED has been designed

with high quality optics and excellent mechanical construction.

The ED glass in the objective lens means you’ll enjoy images

with far less color distortion than those seen in a standard

refractor, and the smooth Crayford focuser will make getting

sharp images a breeze. These instructions will help you set up

and use your telescope tube.

Getting Started

The 80mm f/7.5 ED comes fully assembled from the factory.

The telescope’s optics have been installed and collimated, so

you should not have to make any adjustments to them.

Please keep the original shipping box! In the unlikely event

you should need to ship the telescope back to Orion for war-

ranty repair service, you should use the original packaging.

The box also makes a very good container for storing the tele-

scope when it is not in use.

Attaching the Refractor to a Tripod or Mount

The 80mm f/7.5 ED can be attached to a tripod or mount by

the use of the 1/4"-20 mounting block. The 1/4"-20 shaft of a

sturdy camera tripod will thread into the hole on the mounting

block on the underside of the optical tube.

Optional tube rings can also be used to mount the scope to a

telescope mount. Tube rings with an inner diameter of 100mm

(3.9"), such as Orion item #7371, are needed. If you are using

tube rings, you should rst attach them to your telescope

mount and then lay the optical tube in the tube rings.

Use of Optional Eyepieces, Diagonal, and Finder

Scope

The 80mm ED does not come with a nder scope, diagonal or

eyepieces in order to grant the user the greatest versatility in

customizing the instrument to suit their tastes. However, cer-

tain rules for using accessories still apply.

Any Orion nder scope with a dovetail bracket can be used

with the 80mm f/7.5 ED. Simply unthread the thumbscrew on

the dovetail mount (Figure) and insert the assembled nder

scope and dovetail bracket. Retighten the thumbscrew. Finder

scopes that do not use a dovetail bracket will need to be

attached by other means.

The 80mm ED can use almost any 1.25" diagonal and eye-

piece. Please note that the telescope will not come to focus

without the use of a diagonal or extension tube. To install

a diagonal, unthread the thumbscrew on the 1.25" adapter

(Figure) until it is ush with the interior of the adapter. Insert

the diagonal or extension tube and secure it with the thumb-

Figure. The 80mm f/7.5 ED Refractor optical tube assembly

Dew/Glare shield

Machined aluminum lens cell

Finder scope dovetail mount

2" Crayford focuser

1.25" Eyepiece

adapter

Crayford focuser tension

thumbscrew

Focus wheel (2)

1/4"-20 mounting block

Corporate Ofﬁces: 89 Hangar Way, Watsonville CA 95076 - USA

Toll Free USA & Canada: (800) 447-1001

International: +1(831) 763-7000

Customer Support: [email protected]

may be reproduced, copied, modied or adapted, without the prior written consent of Orion Telescopes & Binoculars.

AN EMPLOYEE-OWNED COMPANY

screw. Then insert the eyepiece into the diagonal or extension

tube and secure it with the thumbscrew.

Use of 2" Eyepieces and Diagonals

A feature of the 80mm ED is its ability to also use 2" barrel-

diameter eyepieces and diagonals. At low magnications, 2"

eyepieces can give a wider eld of view than standard 1.25"

eyepieces. This is especially desirable for observing deep-sky

objects, as many of them appear quite large, but faint. As with

1.25" eyepieces, the 80mm ED will not reach focus with the

2" eyepieces unless a 2" diagonal or extension tube is used.

To use 2" eyepieces, simply loosen the two large thumb-

screws on the 2" adapter (Figure). Once these thumbscrews

are loosened, the entire back end of the focuser, including any

1.25" diagonal and eyepiece that may be attached, comes off,

exposing the 2" diameter focuser drawtube. Now, insert your

2" diagonal into the drawtube and secure with the two thumb-

screws loosened previously. Insert a 2" eyepiece into the diag-

onal, secure it in place with the thumbscrew on the diagonal,

and you’re ready to observe.

Note About the 2" Crayford Focuser

The 80mm ED comes equipped with a Crayford focuser. The

Crayford design allows for smooth, precise focusing without

any image shift that typical rack-and-pinion designs expe-

rience. If you nd that the focus wheels are too tight or too

loose, you can make adjustments to the focuser tension by

using the focuser tension thumbscrew located on the bottom

of the optical tube, between the focus wheels. Make adjust-

ments to this thumbscrew until the focuser motion feels com-

fortable. Please note that you must have at least some tension

applied to the focuser drawtube or else it will not move when

you turn the focus wheels.

Calculating Magnification (Power)

It is desirable to have a range of eyepieces of different focal

lengths, to allow viewing over a range of magnications. To

calculate the magnication, or power, of a telescope, simply

divide the focal length of the telescope by the focal length of

the eyepiece:

Telescope F.L. ÷ Eyepiece F.L. = Magnication

For example, the 80mm ED, which has a focal length of

600mm, used in combination with a 25mm eyepiece, yields

a power of

600 ÷ 25 = 24x.

Every telescope has a useful limit of power of about 45x-60x

per inch of aperture. Claims of higher power by some tele-

scope manufacturers are a misleading advertising gimmick

and should be dismissed. Keep in mind that at higher pow-

ers, an image will always be dimmer and less sharp (this is a

fundamental law of optics). The steadiness of the air (the “see-

ing”) will limit how much magnication an image can tolerate.

Always start viewing with your lowest-power (longest focal

length) eyepiece in the telescope. After you have located and

looked at the object with it, you can try switching to a higher-

power eyepiece to ferret out more detail, if atmospheric con-

ditions permit. If the image you see is not crisp and steady,

reduce the magnication by switching to a longer-focal-length

eyepiece. As a general rule, a small but well-resolved image

will show more detail and provide a more enjoyable view than

a dim and fuzzy, overmagnied image.

Note About Chromatic Aberration

Chromatic aberration literally means color distortion.

Whenever light passes through one material to another, light

of different wavelengths (color) is bent by different amounts.

This is a problem that plagues refractor-type telescopes, since

light passes through both air and glass to form an image. Most

astronomical objects emit a spectrum comprised of many dif-

ferent wavelengths of light, so each wavelength will be bent by

a slightly different amount when passing through a lens. This

results in each color of light reaching precise focus at a slightly

different point, which reduces image sharpness.

The 80mm ED is designed to minimize chromatic aberration.

The objective lens comprises two individual lens elements,

one of which is made of “ED” (Extra-low Dispersion) glass,

a special type of glass that has superior refractive properties

compared to normal types of glass. The use of this ED glass

minimizes the amount of chromatic aberration, resulting in a

cleaner, sharper image compared to that in standard achro-

matic telescopes.

Photography with the 80mm ED Refractor

With an optional camera adapter, the 80mm f/7.5 ED becomes

a 600mm f/7.5 telephoto lens for a single-lens reex camera.

For long-distance terrestrial or astronomical photography, you

need only a T-ring for your particular camera model. The T-ring

attaches to your camera and threads onto the 80mm ED’s

focuser drawtube, coupling the camera body to the telescope.

Use the camera’s viewnder to frame the picture. Use the tele-

scope’s focuser to focus the image. Tighten the focuser ten-

sion thumbscrew to make sure the camera does not slip out

of focus.

You may want to consider using a remote shutter release

instead of the shutter release on the camera. Touching the

camera can vibrate the system and blur the resulting photo-

graphic image. Also, be sure to use a solid tripod.

Care & Maintenance

Give your telescope reasonable care and it will last a lifetime.

When not in use, keep its dust cover on as well as the dust cap

on the eyepiece opening. Store it indoors or in a dry garage.

Do not leave the telescope outside except when using it. The

optical tube is aluminum and has a smooth painted surface

that should resist scratches and smudges. If a scratch does

appear on the tube, it will not harm the telescope. Smudges

on the tube can be wiped off with standard household clean-

ers such as Windex or Formula 409.

Any quality optical lens tissue and cleaning uid specically

designed for multi-coated optics can be used to clean the tele-

scope’s objective lens as well as the lenses of eyepieces and

nder scopes. Never use regular glass cleaner or cleaning

uid designed for eyeglasses. Before cleaning with uid and

tissue, however, blow any loose particles off the lens with a

blower bulb or compressed air, or lightly brush the lens with

a soft camel hair brush. Apply some cleaning uid to a tissue,

never directly on the optics. Wipe the lens gently in a circular

motion, then remove any excess uid with a fresh lens tissue.

Oily ngerprints and smudges may be removed using this

method. Use caution; rubbing too hard may scratch the lens!

Clean only a small area at a time, using a fresh lens tissue on

each area. Never reuse tissues.

Specifications

Optical tube: Seamless aluminum

Objective lens diameter: 80mm (3.1")

Objective lens: Achromatic, rear element made of ED glass,

air-spaced

Objective lens coating: Fully multi-coated

Lens cell: Machined aluminum

Focal length: 600mm

Focal ratio: f/7.5

Focuser: Crayford, accepts 1.25" or 2" accessories and

camera T-Ring

Mounting: 1/4"-20 mounting block, optional tube rings

Weight: 5 lbs. 11 oz.

Length: 23.5"

Corporate Ofﬁces: 89 Hangar Way, Watsonville CA 95076 - USA

Toll Free USA & Canada: (800) 447-1001

International: +1(831) 763-7000

Customer Support: [email protected]

may be reproduced, copied, modied or adapted, without the prior written consent of Orion Telescopes & Binoculars.

AN EMPLOYEE-OWNED COMPANY

One-Year Limited Warranty

This Orion product is warranted against defects in materials or workmanship for a peri-

od of one year from the date of purchase. This warranty is for the benet of the original

retail purchaser only. During this warranty period Orion Telescopes & Binoculars will

repair or replace, at Orion’s option, any warranted instrument that proves to be defec-

tive, provided it is returned postage paid. Proof of purchase (such as a copy of the origi-

nal receipt) is required. This warranty is only valid in the country of purchase.

This warranty does not apply if, in Orion’s judgment, the instrument has been abused,

mishandled, or modied, nor does it apply to normal wear and tear. This warranty gives

you specic legal rights. It is not intended to remove or restrict your other legal rights

under applicable local consumer law; your state or national statutory consumer rights

governing the sale of consumer goods remain fully applicable.

For further warranty information, please visit www.OrionTelescopes.com/warranty.

Popular Accessories manuals by other brands

Hillco

Hillco 2810 Operator's manual

Siemens

Siemens QSA2700D Basic documentation

Contours

Contours ZY024 manual

Saivod

Saivod VS621 manual

Virtuox

Virtuox VirtuCLEAN 2.0 user manual

SCE

SCE ENVIRO-THERM SCE-TE170B24VSS user manual

Z-Wave

Z-Wave HSD-200Z user manual

turck

turck FMX-IM-2UPLI63FX quick start guide

Decagon Devices

Decagon Devices 10HS manual

UPPAbaby

UPPAbaby Cup Holder user manual

Elko

Elko SmartSensor Leakage Wireless manual

Grizzly

Grizzly H8371 instructions

Panasonic

Panasonic HG-T Series user manual

IFM Electronic

IFM Electronic Efector 250 Series Brief instructions

DigiDesign

DigiDesign 888/24 I/O installation guide

PROZIS

PROZIS QUAY user manual

patagonia

patagonia PSI Vest user manual

SFC Energy

SFC Energy EFOY GO! manual