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- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
So i've been making my own refracting telescopes. I told ppl that and they said I was crazy, but honestly it's not that hard!! It's an easy diy project if anyone is interested in astronomy, even just a little bit. Seriously all you need is two convex lenses!! My first one was made out of a magnifying glass and an old eyepiece from a microscope. It zoomed from 4x to 6x, somewhere between my two pairs of binoculars. Yeah so the first wasn't good.
here's the science of it:
A larger convex lens collects the light from a distant star. Since these stars are so far away, they usually come in parallel, which makes it easier :p This lens is called the “Objective” lens. The focal point, or point at which it focuses light, is generally bigger=better. It's a little more complicated than that though…Also the aperture (Diameter) should be larger so that it can collect more light to see distant objects.
But it needs a place to go…so you find a tube that is equal to the focal length of the lens. For example if the focal length was 900mm, it would be a 900mm long tube, with the same diameter of the lens. So what's next?
The eyepiece, which is simply a smaller lens. For this lens, the smaller focal point is better!! Why? Because the ratio from the Objective lens to the Eyepiece lens is your total magnification:
so if it was 900mm objective lens focal point and 25mm focal point of the eyepiece, it would be 36x magnification.
For the tube of this one, it should be made so that it can fit nicely inside the larger tube. The length should be around the focal point of the eyepiece, but probably a little more for focusing. All you need to do to focus is just slide it in and out. Its important to note that after a while, the magnification if it gets too high will be worthless. A good rule of thumb for the maximum useful magnification is 2x the Objective lens's diameter in mm.
If you use two convex lenses, it will be upside down. But it's for astronomical viewing so it doesn't really matter…
Also remember that you always want a higher focal ratio!!!! The higher it is, the less Chromatic Aberration, or color fringing will happen!!!!
So there's the basics on how to do it, you should do more research though…
If anyone makes one send pics!!! Or better pics of the views!!!
also if u have any questions, i'll try and answer!!!!
If I get good pics I will send them, so here's a cool diy activity.
Also a comment if you do make your own telescope…beware the chromatic aberration. Make a reflector or use achromatic or apochromatic designs…
here's the science of it:
A larger convex lens collects the light from a distant star. Since these stars are so far away, they usually come in parallel, which makes it easier :p This lens is called the “Objective” lens. The focal point, or point at which it focuses light, is generally bigger=better. It's a little more complicated than that though…Also the aperture (Diameter) should be larger so that it can collect more light to see distant objects.
But it needs a place to go…so you find a tube that is equal to the focal length of the lens. For example if the focal length was 900mm, it would be a 900mm long tube, with the same diameter of the lens. So what's next?
The eyepiece, which is simply a smaller lens. For this lens, the smaller focal point is better!! Why? Because the ratio from the Objective lens to the Eyepiece lens is your total magnification:
so if it was 900mm objective lens focal point and 25mm focal point of the eyepiece, it would be 36x magnification.
For the tube of this one, it should be made so that it can fit nicely inside the larger tube. The length should be around the focal point of the eyepiece, but probably a little more for focusing. All you need to do to focus is just slide it in and out. Its important to note that after a while, the magnification if it gets too high will be worthless. A good rule of thumb for the maximum useful magnification is 2x the Objective lens's diameter in mm.
If you use two convex lenses, it will be upside down. But it's for astronomical viewing so it doesn't really matter…
Also remember that you always want a higher focal ratio!!!! The higher it is, the less Chromatic Aberration, or color fringing will happen!!!!
So there's the basics on how to do it, you should do more research though…
If anyone makes one send pics!!! Or better pics of the views!!!
also if u have any questions, i'll try and answer!!!!
If I get good pics I will send them, so here's a cool diy activity.
THE PICTURES I GOT:GO TO MY PROFILE FOR ALL OF THEM THESE ARE JUST SOME IN FACT THIS HASNT BEEN UPDATED IN FOREVER…
Jupiter and Saturn: Your text to link here…
The moon: Your text to link here…
The Orion Nebula: Your text to link here…
Just Jupiter: Your text to link here…
Hercules clusters: Your text to link here…
Pleiades: Your text to link here…
Andromeda Galaxy: Your text to link here…
Good Saturn: here
Also a comment if you do make your own telescope…beware the chromatic aberration. Make a reflector or use achromatic or apochromatic designs…
Last edited by The-redwall-nerd (April 1, 2026 10:49:26)
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
Pics in above post, all sorted
Last edited by The-redwall-nerd (Jan. 1, 2026 18:32:43)
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
I will put the pics in a project
Last edited by The-redwall-nerd (Dec. 7, 2025 21:33:59)
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
It's not working T-T just look it up
simple refracting telescopes diagram
Last edited by The-redwall-nerd (Dec. 7, 2025 21:34:13)
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
I made a scratch project to help you understand: here…
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
Just got my objective lens today!! Going to start building. Will share images if cool and good!
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
Alrighty!!! Got pics and they work now!! Here you go!!Tried to get more tonight but far too cloudy to see anything at all
telescope pictures…
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
Cloudy again, but I have the photos in my projectAlrighty!!! Got pics and they work now!! Here you go!!Tried to get more tonight but far too cloudy to see anything at all
telescope pictures…
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
New pics, this time of Jupiter and 3 of its moons!!!
Jupiter.
Taken from my Refractor whom is titled ‘Copernicus’
Jupiter.
Taken from my Refractor whom is titled ‘Copernicus’
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
Got more better pictures of the Orion Nebula M42 in this project!! Taken with my diy refractor!!
Orion Nebula!!
If you want to see more the studio for it is linked in my signature
Orion Nebula!!
If you want to see more the studio for it is linked in my signature
Last edited by The-redwall-nerd (Dec. 21, 2025 21:47:36)
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
Yesterday I got new pictures from planetary filters I got for Christmas, and it really helped show detail on planets! See my results in my project: Jupiter and Saturn
Can see rings of Saturn and bands of Jupiter!!!
Can see rings of Saturn and bands of Jupiter!!!
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
Yesterday I got new pictures from planetary filters I got for Christmas, and it really helped show detail on planets! See my results in my project: Jupiter and SaturnI added more photos to the project of Jupiter and Saturn of Jupiter, to help see the bands better! Check it out!
Can see rings of Saturn and bands of Jupiter!!!
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
Not really telescope news, but Betelgeuse is supposed to go supernova in the next 100,000 years, there’s already a chance it has actually!
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
New pics of Saturn, better much better, you can see the rings so so much better!!!
Your text to link here…
Your text to link here…
Last edited by The-redwall-nerd (Jan. 12, 2026 00:47:47)
- Unknown9856
-
Scratcher
68 posts
Making and creating telescopes observatory - this week- some pretty stars
Can I post my own telescope pictures here?
- The-redwall-nerd
-
Scratcher
100+ posts
Making and creating telescopes observatory - this week- some pretty stars
Can I post my own telescope pictures here?Sure! I’d love to see them!!
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