How to Assemble a Telescope Eyepiece

Eyepieces go on the back of the telescope.

The eyepiece of a telescope attaches to the optic chamber on the back of the telescope. This is where the eye positions to view and locate stars, planets and celestial objects. Assembling these lenses means putting them onto the telescope and properly aligning them. Handle the eyepieces with care, as they are highly calibrated pieces of optic equipment and are sensitive to jolts and jerky actions.

Instructions

1. Point the telescope out of the sun. Look down the end of the telescope and down the tube. Check that the diagonal mirror --also called the secondary-- is in the center of the telescope and at a 45 degree angle in the tube.

2. Remove any caps or old eyepieces on the focuser tube. Look into the tube to ensure the diagonal mirror is reflecting back to the focus tube.

3. Push the new eye piece onto the focus tube and look down into the eyepiece. The image through the eyepiece should be a small version of the diagonal mirror reflection.

4. Point the telescope at a far off object away from the sun if focusing and adjusting the eyepiece during the day. Turn the focus dial to bring the object into clear vision.

References

• T Pub: Section XXIX: Telescope Eyepieces
• Orion: Collimating Eyepiece #3640: PDF