How do you mark the center of a primary mirror?
To do this, carefully place the mirror shiny side down on a clean sheet of paper and trace its outline with a pencil. Cut out the circle, then carefully fold it into quarters to find its exact centre.
What does a primary mirror do?
The primary mirror reflects the light of the celestial object to the prime focus near the upper end of the tube. Obviously, if an observer put his eye there to observe with a modest-sized reflector, he would block out the light from the primary mirror with his head.
How do you clean the primary mirror in a reflector telescope?
Fill the plastic bowl with tepid water and a couple of drops of detergent. Gently place the primary mirror in the soapy water and leave it to soak for five minutes. Rinse using tepid water and place on a towel with the mirror surface at an angle.
How do you center a secondary mirror?
To center the secondary mirror under the focuser, hold the mirror holder in place with one hand while adjusting the center bolt with a Phillips screwdriver. Do not touch the mirror’s surface!
What is a collimation cap?
Collimation cap: A collimation cap, or sight tube, is a plug that fits in your reflector’s focuser. It has a small central hole. Although it’s mainly used to ensure that your secondary mirror is aligned with respect to your focuser, it can also be used to ensure correct alignment of the secondary and primary mirrors.
What is the purpose of a secondary mirror?
Secondary mirrors in the form of an optically flat diagonal mirror are used to re-direct the light path in designs such as Newtonian reflectors. They are also used to re-direct and extend the light path and modify the final image in designs such as Cassegrain reflectors.
What is the primary mirror of a telescope?
A primary mirror (or primary) is the principal light-gathering surface (the objective) of a reflecting telescope.
When should I clean my primary mirror?
The more you use it, the more likely small particles of dust are to find their way into your optical tube and get stuck on one of the mirrors. Usually, people clean their mirrors once every 5 to 10 years, but you may need to do it more often than that depending on the conditions of the air where you live and image.
What happens if telescope is not collimated?
If your telescope is not properly collimated, it will be impossible to properly focus, no matter the sky conditions.
How do you mark the centre of a mirror?
Step #3: Dot the centre of the mirror. Gently lay the paper circle onto the face of the primary mirror so that its edge aligns with that of the mirror. Using a fine-tip permanent marker, make a mark on the mirror’s centre.
How to fix a broken primary mirror on a telescope?
Step #1: Remove the primary mirror. Your telescope’s main mirror is housed in a cell that normally attaches to the tube with a few small screws. Before removing these, stick a small strip of masking tape to the mirror cell and tube to index it so that you can put it back together the same way.
How to make a paper circle on a scope mirror?
Gently lay the paper circle onto the face of the primary mirror so that its edge aligns with that of the mirror. Using a fine-tip permanent marker, make a mark on the mirror’s centre. Step #4: Add the “doughnut.” This step is necessary because seeing a tiny dot while looking in your scope’s focuser is very difficult — especially in the dark.