Z850 SERIES 

ZOOM STEREO MICROSCOPE 

MANUAL 

73 Mall Drive, Commack, NY 11725 • 631-543-2000 (P) • 631-589-6975 (F) 

www.unitronusa.com • info@unitronusa.com 
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 2

CONTENTS 

SAFETY NOTES .................................................................................................................. 3 

CARE AND MAINTENANCE ................................................................................................ 3 

INTRODUCTION .................................................................................................................. 4 

UNPACKING AND COMPONENTS ..................................................................................... 4 

COMPONENTS DIAGRAM .................................................................................................. 4 

ASSEMBLY .......................................................................................................................... 5 

DETAILED ASSEMBLY PROCEDURE ................................................................................ 6 

ADJUSMENT AND OPERATION 

ADJUSTING BINOCULAR VIEWING HEAD ................................................................... 8 

FOCUS ADJUSTMENT ................................................................................................... 9 

SPECIFICATIONS .............................................................................................................. 10 

TROUBLESHOOTING ........................................................................................................ 11 

MAINTENANCE.................................................................................................................. 12 

SERVICE ............................................................................................................................ 12 

WARRANTY ....................................................................................................................... 12

 
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 3

SAFETY NOTES 

1. Open the shipping carton carefully to prevent any accessory, i.e. objectives or eyepieces, from 

dropping and being damaged. 

2. Keep the instrument out of direct sunlight, high temperature or humidity, and dusty environments. 

 

3. If any specimen solutions or other liquids splash onto the stage, objective or any other component, 

disconnect the power cord immediately and wipe up the spillage. Otherwise, the instrument may be 

damaged. 

4. LAMP REPLACEMENT -- CAUTION: the glass envelope of the lamp may be extremely 

hot. DO NOT attempt to change the lamp before it is completely cooled or without 

wearing adequate skin protection. 

5. All electrical connectors (power cord) should be inserted into an electrical surge protector to prevent 

damage due to voltage fluctuations. 

6. FUSE REPLACEMENT -- For safety when replacing the fuse (ONLY replace with the 

same size, type and rating of original fuse), be sure the main switch is in the off position, 

disconnect the power cord from outlet, and replace the fuse. Reconnect the power cord 

and turn unit on. 

7. Confirm that the input voltage indicated on your microscope corresponds to your line voltage. The 

use of a different input voltage other than indicated will cause severe damage to the microscope. 

 NOTE: Always plug the stereomicroscope power cord into a suitable grounded electrical outlet. A 

grounded 3-wire cord is provided. 

CARE AND MAINTENANCE

1. Do not attempt to disassemble any component including eyepieces, objectives or focusing assembly. 

2. Keep the instrument clean; remove dirt and debris regularly. Accumulated dirt on metal surfaces 

should be cleaned with a damp cloth. More persistent dirt should be removed using a mild soap 

solution. Do not use organic solvents for cleansing. 

3. The outer surface of the optics should be inspected and cleaned periodically using an air stream from 

an air bulb. If dirt remains on the optical surface, use a soft, lint free cloth or cotton swab dampened 

with a lens cleaning solution (available at camera stores). All optical lenses should be swabbed using

a circular motion. A small amount of absorbent cotton wound on the end of a tapered stick makes a 

useful tool for cleaning recessed optical surfaces. Avoid using an excessive amount of solvents as 

this may cause problems with optical coatings or cemented optics or the flowing solvent may pick up 

grease making cleaning more difficult. 

4. Store the instrument in a cool, dry environment. Cover the microscope with the dust cover when not 

in use. 

5. UNITRON® microscopes are precision instruments which require periodic servicing to maintain 

proper performance and to compensate for normal wear. A regular schedule of preventative 

maintenance by qualified personnel is highly recommended. Your authorized UNITRON® distributor 

can arrange for this service. 
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 4

INTRODUCTION 

Congratulations on the purchase of your new UNITRON® microscope. UNITRON® microscopes are 

engineered and manufactured to the highest quality standards. Your microscope will last a lifetime if 

used and maintained properly. UNITRON® microscopes are carefully assembled, inspected and tested

by our staff of trained technicians in our New York facility. Careful quality control procedures ensure each 

microscope is of the highest quality prior to shipment. 

UNPACKING AND COMPONENTS 

Your microscope arrived packed in a molded shipping carton. Do not discard the carton: the shipping 

carton should be retained for reshipment of your microscope if needed. Avoid placing the microscope in 

dusty surroundings or in high temperature or humid areas as mold and mildew can form. Carefully 

remove the microscope from the shipping carton and place the microscope on a flat, vibration-free 

surface. 

COMPONENTS DIAGRAM

NOTE: Stand ordered may not be as pictured above. 

 

Binocular Head 

Stand 

Focusing Knob 

Power Cord 

Shift Knob 

Base Switch 

Eyepieces 

Lock-screw 

Stage Plate 
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 5

ASSEMBLY 

The diagram below shows how to assemble the various modules. The numbers indicate the order of 

assembly. 

When assembling the microscope, make sure that all parts are free of dust and dirt, and avoid scratching 

any parts or touching glass surfaces. 

 

Eyepieces 

Binocular Head 

Power Cord 

Stand 

Lock-screw 
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 6

DETAILED ASSEMBLY PROCEDURE 

Mounting the Binocular Head (Fig. 1) 

Loosen the clamping knob 3 on the focus 

mount 4 and insert the binocular head and 

zoom body assembly 2 into the bracket of the 

focus mount, then tighten the lock screw 3. 

Mounting the Eyepieces (Fig. 1, Fig. 2, Fig. 3) 

Remove the eyepiece dust caps 1 (Fig. 1) and 

gently insert the two adjustable eyepieces 5

(Fig. 2) into the eyepiece sleeves until they stop, 

as shown in Fig.3. Replace the dust caps when 

not in use.

IMPORTANT 

ENVIRONMENT REQUIREMENTS 

1 Ambient temperature: 0°C to 40°C (32°F 

to 104°F),Maximum R.H:85%。

2 High temperature will result in moisture 

and mildew and could damage instrument. 

3 Avoid placing the instrument in a dusty 

environment. When not in use, cover the 

microscope with the dust cover. 

4 Keep the microscope on a flat and stable 

surface. 

 

Fig. 1

Fig. 2

Fig. 3
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 7

For Microscopes Purchased 

With Illuminated Stands 

VOLTAGE CHECK 

Confirm that the input voltage indicated on the 

rear label of the microscope corresponds to your 

line voltage. The use of a different input voltage 

than indicated will cause severe damage to your 

microscope. 

Connecting the Power Cord (Fig. 4) 

Turn the power switch 6 to the off position (O) 

before connecting the power cord 7. 

Insert the power cord plug 7 into the power jack 

of the microscope; make sure the connection is 

snug. 

Plug the power cord 8 into the power supply 

receptacle. 

Using the Glass Stage (Fig. 5) 

Set the glass stage plate 9 on the center of the 

base, and secure the slide with the two clips 10.

 

Fig. 4

Fig. 5

Fig. 6
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 8

ADJUSTMENT 

AND OPERATION 

Adjusting Binocular Viewing Head 

Adjusting Interpupillary Distance (Fig. 6) 

Different users have different interpupillary 

distances (this distance is between the centers 

of the pupils of each eye). When the operator 

changes, it will be necessary to adjust the 

interpupillary distance. 

While looking through the eyepieces, hold the 

left and right eyetubes of the viewing head and 

adjust the eyetubes by opening or closing them 

until the left and right fields of view coincide 

completely and you are able to see a complete 

circle. 

Adjusting Diopter Ring (Fig. 7) 

Set the dioptor rings 2 of both eyepieces to “0” 

position. (Do this when users change, because 

different users will have different diopter 

settings.) 

Place an easy-to-observe specimen on the 

stage plate, i.e., a coin. 

Rotate the zoom knob 3 to the highest 

magnification 5x, then turn the focusing knob 4

to focus the specimen. 

Rotate the zoom knob 3 to the lowest 

magnification 0.8x, looking only into the left 

eyepiece, adjust the diopter ring on left eyepiece 

to focus the specimen. Then repeat procedure 

for the right eyepiece.

NOTE: The working distance (the distance 

between the microscope objective to the top of 

the specimen) of the microscope is 115mm, the 

binocular head bracket 5 can be mounted onto 

higher or lower positions according to your 

needs by removing the clamping bolt with the 

Allen wrench provided.

Fig. 6

Fig. 7
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 9

Focus Adjustment 

Adjusting the Rotation Tension of the 

Focus Adjustment Knob (Fig. 8, Fig. 9) 

To adjust tension, hold both left and right focus 

adjustment knobs 1 with both hands, hold the 

left knob (to prevent it from turning), and rotate 

the right knob clockwise to increase (tighten) or 

counterclockwise to decrease (loosen) the focus 

knob tension. 

After tension adjustment has been completed, 

always rotate both adjustment knobs in the 

same direction. 

Changing the Magnification 

The zooming knobs located on both sides of the 

zooming body will change the magnification of 

the specimen image. 

Total Magnification = Magnification of zoom 

body x magnification of eyepiece 

(i.e., 0.8 x 10=8x) 

NOTE: If using any of the optional auxiliary 

objectives, then the above magnification would 

be multiplied by auxiliary objective magnification. 

(i.e., auxiliary 0.5 x 8=4x) 

Moving the Microscope (Fig. 10) 

Before moving the microscope, be sure to 

remove any slide/samples. When moving the 

microscope, hold the stand and base as shown 

in Fig. 10 to keep it level.

Fig. 8

Fig. 9

Fig. 10
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 10

SPECIFICATIONS 

Zoom ratio: 6/1 to 1 

Objective magnification: 0.8x~5.0x 

Eyepiece: Φ 22 10x Wide Field, interpulpillary adjustable

Binocular viewing head: Inclined at 45 degrees, interpupillary distance range: 52~75mm 

Working distance: 115mm 

Range of movement: 105mm 

Illumination system: LED lamp illumination 

Input: 100-240V~, 0.15A, 50.60HZ 

Auxiliary 

Objective 

Working 

Distance

(mm) 

Eyepiece 

WF10X/22 WF15X/16 WF20X/12.5 

Total 

Magnification 

Visual Field 

(mm) 

Total 

Magnification 

Visual Field 

(mm) 

Total 

Magnification 

Visual Field 

(mm) 

 115 8-50X 27.5-4.4 12-75X 20.0-3.2 16-100X 15.6-2.5 

0.5X 211 4-25X 55.0-8.8 6-37.5X 40.0-6.4 8-50X 31.2-5.0 

2X 43.5 16-100X 13.8-2.2 24-150X 10.0-1.6 32-200X 7.8-1.3 
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 11

TROUBLESHOOTING 

Under certain conditions, performance of this unit may be adversely affected by factors other than 

defects. If a problem occurs, please review the following list and take remedial action as needed. If you 

cannot solve the problem after checking the entire list, please contact your local dealer for assistance. 

Trouble Cause Remedy 

Double images Interpupillary distance is not correct Readjust it 

Diopter adjustment is not correct Readjust it 

Dirt appears in the view field Dirt on the specimen Clean specimen 

Dirt on the surfaces of eyepieces Clean eyepieces 

Image is not clear Dirt on the surface of objectives Clear objectives 

Image is not clear while focusing 

change 

Diopter adjustment is not correct Readjust diopter 

Focusing is not correct Readjust it 

The focusing knob is not smooth The focusing knob is too tight Loosen it to a suitable position 

The image is obscure because of the 

head slipping down during 

observation 

The focusing knob is to o loosen Tighten it to a suitable position 
Z850 STEREO MICROSCOPE 

 

UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 12

MAINTENANCE 

Please remember to never leave the microscope with eyepieces removed and always protect the 

microscope with the dust cover when not in use. 

SERVICE 

UNITRON® microscopes are precision instruments which require periodic servicing to keep them 

performing properly and to compensate for normal wear. A regular schedule of preventative maintenance 

by qualified personnel is highly recommended. Your authorized UNITRON® distributor can arrange for 

this service. Should unexpected problems be experienced with your instrument, proceed as follows: 

1. Contact the UNITRON® distributor from whom you purchased the microscope. Some 

problems can be resolved simply over the telephone. 

2. If it is determined that the microscope should be returned to your UNITRON® distributor or to 

UNITRON® for warranty repair, pack the instrument in its original Styrofoam shipping carton. If you no 

longer have this carton, pack the microscope in a crush-resistant carton with a minimum of three inches 

of a shock absorbing material surrounding it to prevent in-transit damage. The microscope should be 

wrapped in a plastic bag to prevent Styrofoam dust from damaging the microscope. Always ship the 

microscope in an upright position; NEVER SHIP A MICROSCOPE ON ITS SIDE. The microscope or 

component should be shipped prepaid and insured. 

LIMITED MICROSCOPE WARRANTY

This microscope is warranted to be free from defects in material and workmanship for a period of five (5) years for 

mechanical and optical components and one (1) year for electrical components from the date of invoice to the 

original (end user) purchaser. This warranty does not cover damage caused in-transit, misuse, neglect, abuse or 

damage resulting from improper servicing or modification by other then UNITRON® approved service personnel. 

This warranty does not cover any routine maintenance work or any other work, which is reasonably expected to be 

performed by the purchaser. Normal wear is excluded from this warranty. No responsibility is assumed for 

unsatisfactory operating performance due to environmental conditions such as humidity, dust, corrosive chemicals, 

deposition of oil or other foreign matter, spillage or other conditions beyond the control of Unitron Ltd. This 

warranty expressly excludes any liability by Unitron Ltd. for consequential loss or damage on any grounds, such as 

(but not limited to) the non-availability to the End User of the product(s) under warranty or the need to repair work 

processes. Should any defect in material, workmanship or electronic component occur under this warranty contact 

your UNITRON® distributor or UNITRON® at (631) 543-2000. This warranty is limited to the continental United 

States of America. All items returned for warranty repair must be sent freight prepaid and insured to Unitron Ltd., 

73 Mall Drive, Commack, NY 11725 – USA. All warranty repairs will be returned freight prepaid to any destination 

within the continental United States of America. For all foreign warranty repairs, return freight charges are the 

responsibility of the individual/company who returned the merchandise for repair.