Celestron 9x50 Illuminated RACI Finder Scope (Model 93781) Instruction Manual

1. Introduction

The Celestron 9x50 Right Angle Correct Image (RACI) Illuminated Finder Scope is designed to enhance your astronomical observations by providing a bright, sharp, and correctly oriented view of the night sky. This finder scope features 50mm optics, 9X magnification, and a 5-degree apparent field of view, making it easier to locate and track celestial objects. Its right-angle, correct-image design ensures that objects appear right-side up and left-to-right correct, simplifying navigation. The integrated illuminated double-crosshair reticle aids in precise centering of objects.

2. What's in the Box

Upon unpacking, please ensure all components are present:

• Celestron 9x50 Illuminated RACI Finder Scope
• Double Ring Bracket with Integrated Dovetail
• Illuminator with Battery (1 Lithium Ion battery included)

3. Key Features

• 9x50 Optics: Provides 9x magnification with a 50mm objective lens for bright, clear images and a 5-degree field of view.
• Right Angle Correct Image (RACI) Design: Ensures objects are viewed right-side up and correctly oriented left-to-right, simplifying object location.
• Illuminated Double-Crosshair Reticle: Features a battery-powered red LED illuminator for the etched reticle, allowing for precise centering without obscuring stars.
• Adjustable Eyepiece Module: The eyepiece can be rotated for comfortable viewing angles.
• Dovetail Bracket: Easy attachment and removal from most Schmidt-Cassegrain and EdgeHD optical tube assemblies.
• Oversized Thumbscrews: Facilitate easy alignment adjustments.

4. Setup

4.1 Mounting the Finder Scope

The finder scope comes with a sturdy bracket featuring an integrated dovetail. This dovetail allows for easy attachment to and removal from most Schmidt-Cassegrain and EdgeHD optical tube assemblies. Slide the dovetail into the corresponding slot on your telescope until it is securely seated. Tighten any locking screws on your telescope's mount to hold the bracket in place.

Image 1: The Celestron 9x50 RACI Finder Scope mounted on a Schmidt-Cassegrain telescope.

4.2 Battery Installation and Illuminator Attachment

The illuminated reticle requires one Lithium Ion battery, which is included. To install or replace the battery, unscrew the illuminator module from the side of the eyepiece. Insert the battery with the correct polarity as indicated inside the battery compartment. Reattach the illuminator module by screwing it back into place.

Image 2: A hand demonstrating the adjustment of the illuminator module on the finder scope.

4.3 Focusing the Reticle

The reticle can be focused independently of the main finder scope optics. To focus the reticle, look through the finder scope and rotate the eyepiece module until the crosshairs appear sharp and clear against a bright background (e.g., the daytime sky). This adjustment ensures the reticle is in sharp focus for your eye.

4.4 Aligning the Finder Scope

For the finder scope to be useful, it must be aligned with your main telescope. This process is typically done during daylight hours:

1. Point your main telescope at a distant, easily identifiable object (e.g., a distant tree or telephone pole). Center the object in the main telescope's lowest power eyepiece.
2. Look through the finder scope. The object you centered in the main telescope should be visible in the finder scope's field of view.
3. Using the oversized thumbscrews on the finder scope bracket, adjust the finder scope's position until the crosshairs are precisely centered on the same object that is centered in your main telescope's eyepiece.
4. Check the alignment by moving your main telescope to another distant object and verifying that both the finder scope and main telescope are still pointing at the same target. Repeat adjustments if necessary.

5. Operating Instructions

5.1 Using the Illuminated Reticle

To activate the illuminated reticle, turn the on/off knob located on the illuminator module. Rotate the knob to adjust the brightness of the red crosshairs. For optimal viewing, select the lowest brightness setting that allows the reticle to be clearly visible without overpowering the faint objects you are observing. Turn the knob fully counter-clockwise to switch off the illumination when not in use to conserve battery life.

5.2 Locating Objects

Once aligned, use the finder scope to quickly locate celestial objects. The 9x magnification and wide field of view make it easy to sweep the sky and identify targets. The correct-image design means that what you see in the finder scope matches the orientation of what you see with your naked eye, simplifying the process of star hopping or following star charts.

5.3 Eyepiece Rotation

The eyepiece module can be rotated left or right to achieve a comfortable viewing angle, especially when your telescope is pointed at high altitudes or in awkward positions. Simply grasp the eyepiece module and gently rotate it to your desired orientation.

6. Maintenance

6.1 Cleaning Optics

Dust and smudges on optical surfaces can degrade image quality. To clean the lenses:

• Use a soft brush or compressed air to remove loose dust particles.
• For smudges or fingerprints, apply a small amount of optical cleaning fluid to a clean, soft microfiber cloth. Gently wipe the lens surface in a circular motion.
• Avoid touching optical surfaces with your fingers.

6.2 General Care

• Store the finder scope in a clean, dry environment when not in use.
• Protect the lenses with dust caps when storing.
• Avoid exposing the finder scope to extreme temperatures or sudden temperature changes.

7. Troubleshooting

• Reticle not illuminating: Check if the illuminator knob is turned on. Verify the battery is correctly installed and has sufficient charge. Replace the battery if necessary.
• Image blurry: Ensure the reticle is focused for your eye (Section 4.3). If the main view is blurry, ensure the finder scope's objective lens is clean.
• Finder scope not aligned with main telescope: Re-perform the alignment procedure as described in Section 4.4. Ensure the dovetail bracket is securely mounted.

8. Specifications

9. Warranty and Support

This Celestron product is backed by a 2-Year US Warranty. For warranty claims or technical assistance, please contact Celestron's US-based support team. You can find additional information and support resources, including a detailed warranty document, on the Celestron website or by referring to the provided Warranty (PDF).

For further inquiries or support, please visit the official Celestron website or contact their customer service.