Omegon® V-III Nabla III Microscopes User Manual

Introduction

Congratulations on purchasing your Omegon® V-III Nabla III microscope. This device offers a number of advantages not commonly found in this price range, including excellent DIN optics, adjustable Köhler LED illumination, and high-precision mechanics for outstanding performance. The coaxial adjustment drive of the cross table, combined with a one-handed fine focus drive, allows for relaxed positioning and focusing of the object, enabling users to concentrate fully on observation without removing their hands from the controls.

Setup

Place the microscope on a stable surface with adequate space. The formula for magnification is: total magnification = objective magnification × eyepiece magnification. For example, a 10x eyepiece with a 4x objective yields a total magnification of 40x.

Attention: Remove shipping locks before use! To protect the high-precision mechanics during transport, the stage adjustment is blocked by 2-3 locking screws. Use the provided Allen key for removal.

Overview

Omegon V-III Nabla III B – Binocular Version

Diagram of the Omegon V-III Nabla III Binocular Microscope. Key components are labeled:

• 1. Eyepiece
• 2. Diopter adjustment
• 3. Insert bracket
• 4. Specimen holder
• 5. Aperture diaphragm lever
• 6. Condenser
• 7. Filter
• 8. Field diaphragm ring
• 9. Binocular head
• 10. Binocular head locking screw
• 11. Body
• 12. Nosepiece
• 13. Objective
• 14. XY Stage
• 15. Condenser locking screw
• 16. Coaxial stage controls
• 17. Handle
• 18. Power inlet
• 19. Fuse
• 20. On/Off Switch
• 21. Focus adjustment for condenser
• 22. Coarse focus control
• 23. Fine focus control
• 24. Tension adjustment ring

Features

The Omegon V-III Nabla III series biological microscopes are designed for teaching in universities, colleges, and secondary schools, as well as for clinical laboratory tests. The ergonomic design ensures comfortable operation and reduces user fatigue. This transmitted light microscope offers a compact design and flexibility.

Key features include:

• Ergonomically designed metal frame for stability and durability.
• Integrated carrying handle on the tripod for easy transport.
• Tripod and base made from a single piece.
• Antifungal treatment to prevent fungal growth.
• Cable holder for convenient storage.
• Siedentopf eyepiece tubes with adjustable eye relief (48mm – 75mm).
• 360° head rotation.
• 10x widefield focus eyepieces with high eye relief and a 22mm field of view, suitable for eyeglass wearers.
• Diopter adjustment on both eyepieces for compensating ametropia, with diopter scales for easy setting. Parfocality is maintained by independent diopter adjustment.
• Optional crosshair eyepiece for measurements (0.1 mm/1 cm grid, 0.1 mm/1 cm crosshair, or simple crosshair).
• Rotating inverted quadruple objective turret with color-coded, parcentric, and parfocal DIN objectives, running on ball bearings with internal detent stops.
• Finite “Plan-ACHROMAT” DIN objectives: 4x, 10x, 40x, and 100x/oil.
• Retractable 40XR and 100XR objectives with durable mounts.
• Convenient low-position coaxial coarse and fine adjustment (37.7 mm coarse stroke per rotation, 0.1 mm/circle fine adjustment with 1 µm increments). Focusing range of 16 mm.
• 21.6 cm x 15 cm built-in double-layer mechanical stage with graphite surface, rounded edges, and a smooth calibrated X/Y movement (7.5 cm x 5.5 cm transverse movement).
• Built-in Köhler illumination with continuously adjustable LED source and light intensity control.
• Full Köhler N.A. 1.25 Abbe condensers with rack and pinion height adjustment and an integrated adjustable diaphragm stop.
• Trinocular phototube (50% visible, 50% open) for optional 10 MP digital eyepiece cameras and 8-inch LCD cameras for photo and video documentation.

Assembly

Unpack the instrument and accessories carefully, retaining original packaging for storage or return. Always keep the microscope in a clean, dry, and dust-free environment.

Use two hands to carry the microscope. Ensure all components are secured before transport. Never carry the microscope upside down. Set up on a stable worktable with a smooth tabletop. Avoid touching optical surfaces.

1. Mount the binocular or trinocular head onto the stand.
2. Screw the supplied objective lenses into the nosepiece mounts in order of increasing power.
3. Insert the supplied eyepieces into the microscope head.
4. Mount the condenser/Köhler unit into its holder:
   • Raise the specimen stage to its highest position using coarse focus knobs.
   • Lower the condenser to its lowest position using the condenser focus knob.
   • Loosen the condenser clamping screw, position the condenser in the holder, and tighten the clamping screw.
   • Raise the condenser to a working position using the condenser focus screw.
5. Slide the illumination unit into the microscope base.
6. Slide the filter holder into the microscope stand.
7. If using the trinocular version, screw the CCD adapter onto the photo output of the head.

Calibration

Place a slide with a specimen on the mechanical stage. Position the desired part of the specimen under the objective. Select the 4x objective and move the stage to its highest position. Adjust the condenser to its highest position. Turn on the light source and adjust brightness. Use the coarse focus knob until an image is visible, then use the fine focus knob to bring it into sharp focus.

Quick Start

1. Using the binocular microscope:

Rotate the nosepiece to select the desired magnification. Focus the specimen using coarse and fine focus knobs until it appears sharp in the right eyepiece. Insert an eyepiece of the same magnification into the left eyepiece tube. Adjust the binocular head by rotating the eyepieces until the interpupillary distance matches your eyes, allowing you to see a single round image. The scale on the dial between the eyepieces indicates the pupil distance.

Diagram of a binocular microscope head (Figure 2):

• 1. Diopter adjustment for the left eyepiece
• 2. Left eyepiece
• 3. Scale for eye distance
• 4. Right eyepiece

Adjust the diopter ring on the left eyepiece until the image in the left eyepiece is as sharp as in the right. The binocular adjustment is complete. You can center the specimen using the coaxial stage adjustment.

Rotate the condenser to its highest position and adjust the aperture diaphragm handle for optimal resolution and contrast. It is recommended to set the aperture diaphragm so its image diameter is 70–85% of the objective's pupil diameter. For 100x oil immersion, apply immersion oil to the specimen and objective, then carefully move the objective into the oil.

2. Using the trinocular microscope:

Unpacking, installation, and calibration are similar to the binocular version. The trinocular variant includes a camera port for connecting a camera.

Full Operating Procedure for Brightfield Observations

1. Turn the nosepiece until the 4x objective clicks into place.
2. Use the coarse focus adjustment to move the cross table down.
3. Place a slide on the cross table and clamp it with the slide lock lever.
4. Use coaxial adjustment to move the object into the field of view.
5. Switch on the light source and adjust intensity for proper brightness.
6. Adjusting interpupillary distance and viewing height: Swing eyepiece tubes to match your interpupillary distance, ensuring a single round image. Set diopter rings on both eyepieces to the '0' position.
7. Bring the specimen into focus using coarse and fine adjustment knobs. Slowly turn the coarse adjustment knob clockwise until the image is bright and clear. Use fine focus knobs for minor adjustments.
8. Compensating for ametropia: Both eyepieces have focusing rings for vision correction. Turn the diopter ring counterclockwise to its stop. With your left eye, look through the left eyepiece and slowly turn the diopter ring clockwise until the object is in focus. Repeat for the right eye. Gently refocus if necessary. For reticule eyepieces, focus the reticule first, then the specimen.

Notes:

• Use cover glasses of 0.17mm thickness for optimal objective performance.
• Use specimen slides of 0.9 to 1.4mm thickness.
• Interpupillary and diopter adjustments should be made each time the observer changes.

Obtaining Proper Köhler Illumination

Follow these steps for optimal illumination:

1. With the 4x objective engaged and specimen in focus, close the field diaphragm ring clockwise to its minimum size (Figure 1).
2. Adjust the condenser height using the sub-stage condenser focusing knob to bring the field diaphragm image into focus (Figure 2).
3. Center the field diaphragm image in the eyepiece field of view using the sub-stage condenser centering screws (Figure 3).
4. To check centration, open the field diaphragm until its image touches the field of view perimeter. Re-center if necessary.
5. For observation, open the field diaphragm until its image is slightly larger than the field of view (Figure 4).
6. Carefully adjust the sub-stage condenser iris diaphragm for optimal contrast. Remove one eyepiece and look through the tube to adjust the aperture diaphragm. The aperture diaphragm determines the numerical aperture of the illumination system and is crucial for resolution and contrast. Aim for approximately 2/3 to 4/5 of the objective's exit pupil diameter.

Notes:

• Aperture adjustment and condenser focusing are critical for objective performance.
• Setting the condenser aperture iris diaphragm to 70-80% of the objective's N.A. is recommended for optimum contrast and resolution.

Use of the 100XR, Oil Immersion Objective

• Focus on the specimen, switching from lowest to highest power objectives.
• Before engaging the immersion objective, place a drop of immersion oil on the specimen.
• Turn the revolving nosepiece to engage the immersion objective and focus with the fine adjustment knob.
• Ensure the oil is free of bubbles by moving the objective back and forth.
• Immersion oil is used between the slide and condenser, and between the objective and cover slip.
• After use, clean the objective front lens with gauze moistened with a 70% ether / 30% alcohol mixture.

Optional Accessories

Dark Field Observation

Two types of dark field condensers are available: dry (NA 1.25) and oil (NA 1.25–1.36). Replace the condenser if necessary. For dark field observation with oil, ensure oil is applied between the condenser and object carrier, and between the object carrier and lens. Open the field diaphragm and observe the sample.

Observations in Polarized Light

A polarization set includes a polarizer and an analyzer. Screw the polarizer into the condenser. Insert the analyzer into the notch.

Note: Condenser N.A. engraving applies when oil is present between the slide and condenser top surface; without oil, N.A. is approximately 0.9.

Storage

• Ensure light intensity is at its lowest setting and the base switch is off.
• Store the microscope with a protective dust cover in a low humidity environment.
• Keep all eyepieces, objectives, and accessories in place during storage.

Maintenance and Troubleshooting

Microscopes undergo testing before delivery. Disassembly is not permitted. Store the instrument in a shady, cool, dry environment. Treat lenses carefully. Keep optical components in a moisture-tight box when not in use. Switch off the power, unplug the mains, and cover the instrument after use. Ensure the power supply's ground connection is in good condition.

Appendix 1 provides information on common mistakes, causes, and troubleshooting methods. Contact the seller if issues cannot be resolved.

Appendix 1: Troubleshooting

Appendix 2: Technical Data

Objectives: