How to make a homemade astronomical telescope simple .

A large-aperture convex lens (with a long focal length) is used as the objective, and a shorter focal length (the shorter the better) is used as the eyepiece. If you want to multiply, put a concave lens between the eyepiece and the objective.

How much do you estimate it will cost?

1. First of all, the objective lens, find a lens with a focal length of 80 cm, be sure to have a plano-convex lens, a suitable lens is generally between the aperture and the focal length ratio of 1:8 or 1:15, such as a lens with a diameter of 5 cm, press 1:

15 to calculate, 5x15 = 75 cm. If it is calculated according to 1:8, that is, 5x8 = 40 cm, which means that a lens with a diameter of 5 cm, the focal length between 40-80 cm is suitable, and the telescope imaging made is still good, and the telescope imaging made by too much is lower or more than this range will be very poor.

2. I use whiteboard paper (thick paper) to roll the outer cylinder of the lens, mainly to facilitate the installation of the objective tube, the thickness of the roll is determined by the inner diameter of the objective tube you have, and the diameter of the roll is just put into the objective tube. Roll the objective tube to the same diameter as the objective.

3. Eyepiece, the focal length of about 3 cm can form a composite eyepiece with a focal length of about centimeter, if you want to achieve achromatic, the distance between the two lenses is two-thirds of the focal length of a single piece, and the focal length can be shortened to three-quarters of the original single focal length, and the magnification of the telescope is the focal length of the objective lens divided by the focal length of the eyepiece is equal to the magnification.

The tutorial of making a homemade high-powered astronomical telescope is as follows:

Equipment】 Yellow cardboard, convex lens.

Production] 1. Choose a convex lens with a focal length of 30 to 50 mm as an eyepiece, which can be replaced by a magnifying glass for repairing clocks. Use a convex lens with a focal length of about 1 meter as an objective, which can be replaced by 100-degree presbyoptic spectacle lenses.

2. Determine the focal length of the convex lens to determine the length of the lens barrel. Place the objective lens and eyepiece facing the sun respectively, put a piece of white cardboard on the other side of the lens, adjust the distance between the paper and the lens, so that the sun is clearly imaged on the white cardboard, and measure the distance between the lens and the paper with a ruler is the focal length of the lens.

3. The lens barrel is made of yellow board paper. The entire tube is divided into two sections: the objective tube and the eyepiece tube.

The diameter of the objective tube is approximately equal to the diameter of the objective lens and the length is approximately equal to the focal length of the objective. The outer diameter of the eyepiece tube is slightly smaller than the inner diameter of the objective tube, allowing the eyepiece barrel to be inserted into the objective tube and the focal length can be adjusted back and forth. The inner diameter of the eyepiece barrel is approximately equal to the diameter of the eyepiece lens and is 100 mm longer than the eyepiece focal length.

The barrel is made by cutting the yellow board paper into strips of paper 70 to 80 mm wide. Find a tube with a diameter equal to the diameter of the lens as the core. Wrap the yellow board paper strip around the core, one by one, without overlapping or gaping, and the two ends of the paper strip and the joint can be connected with glued kraft paper.

After the first layer is rolled, glue is applied to the outside of the yellow cardboard, and then the second layer is rolled in the opposite direction to the first layer.

After rolling, then apply glue and roll the third layer, the direction of winding is opposite to the second layer, generally three layers can be wound, the outermost layer of kraft paper is pasted, the core is removed, and it is placed vertically indoors to dry. After drying, the inner layer of the lens barrel is blackened with black ink to eliminate the influence of stray light on observation.

4. Install the lens in the lens barrel, so that the main optical axis of the objective lens and eyepiece is on the center line of the lens tube. The installation of the lens should be determined according to the size of the lens, the diameter of the lens is smaller than the inner diameter of the lens barrel can be installed according to Figure 19-4a, and the lens diameter is equal to the inner diameter of the lens barrel can be installed according to the way of b in the figure.

After the lens is installed, the eyepiece tube can be inserted into the objective lens barrel, aimed at the distant light with the eye, adjust the front and rear positions of the program lens and the objective lens, so that the distant light falls on the field of view seen by the telescope**, which indicates that the main optical axis of the eyepiece falls on the center line of the lens tube, otherwise the position of the eyepiece needs to be adjusted appropriately until it meets the requirements.

5) Install a bracket on the lens tube, which can be a movable tripod or another form, but it must make the lens barrel very stable when rotating. The bracket should be installed at the center of gravity of the telescope tube. There should be enough friction at the place of connection so that the telescope can stay in any position and be stable.

If you can't do anything for 100 yuan, you can go to ** to see and buy a lens group, which refracts 60 caliber, maybe less than 100 yuan, and reflects 114 caliber 100 yuan.

Materials: generally need objective lenses, eyepieces, PVC plastic pipes larger than the objective lens (go to larger hardware stores, remember to be drainage pipes, don't buy water pipes), tripods, lens tube hoops, etc., the equatorial mount is expensive, EQ3 load-bearing 5kg, about 400 yuan, sandpaper, hacksaws, files, knives, 502, pliers, various screws and other tool accessories.

The magnification of the telescope = the focal length of the objective eyepiece The focal length of the eyepiece in mm<>

I made my own reflective 150mm aperture, I need materials: ** buy 150mm reflective objective lens set 220 yuan, 160mm pvc plastic pipe 1 meter 15 yuan (to make the lens tube), 160mm pvc plug and seal 20 yuan (fixed objective), reflection focusing gear 120 yuan, 160mm steel hoop pair 20 yuan, in addition to various wood, tools, a total of 100 yuan.

Here's how to make an astronomical telescope:Material preparation: objective lens, eyepiece, PVC water pipe, etc.

Operation steps: 1. Select a PVC water pipe of appropriate size, measure the length, and cut it.

2. Clean up the nozzle incision.

3. The objective lens is a two-piece achromatic objective lens group (one convex lens and one concave lens). When attaching, if you make it simple, you can directly stack the two pieces together, making sure that the convex lens is in the front (facing the scene) and the concave lens is in the back (facing the lens barrel).

4. Installation of eyepieces. The eyepiece of choice is a PL20mm eyepiece with an 18x combination with a 51F360 objective.

5. Then roll the eyepiece in cardboard and wrap it with tape.

6. Use transparent glue to fix the quick-release plate around the PVC lens barrel a few times, and then you can set the telescope on the tripod.