Telescope Basics 1 (of 6): Top three telescope types explained

Hosted by David Fuller of “Eyes on the Sky,” this video covers the the three basic types of amateur astronomy telescopes: Refractors, reflectors and compound telescopes. It gives an overview of each one, as well as comparing and contrasting the advantages and disadvantages of each type of design. An excellent primer for anyone wanting to understand more about telescopes.



TheSecretAgent says:

this is really great, and helpful, but i think it would be even better if you visually showed what the type of optical differences the telescopes had… for example–if there is less light, does that mean it’s dimmer? if so, show me what that might look like

Ed McMaster says: to the hobby, will be following you..thanks..

Denise Greenberg says:

Excellent video! I am using this in my astronomy class today.

Andrew Jackson says:

I’ve only ever bought 1 reflector, won’t buy another. Refractors for me all the way.

HengHeng Heng says:


Charlie Fuller says:

Nice last name! aha

Eyes on the Sky says:

Search my YouTube channel for my Funscope/Firstscope review comparison. Should answer all your questions, since I’m limited on characters here. A Google search for “Funscope review” should probably bring up my website’s review page pretty high in results as well.

wency brown says:

your videos are very helpful in my physics class! Thank you so much

DeathNote 7 says:

I’m ordering a Orion 8-inch dobsonian telescope today. Is there anything I should know?

Eyes on the Sky says:

You’re welcome – glad you enjoy them, and thanks for the nice comment! Be sure to check out my weekly videos where I show how to find objects in the sky too.

shashi ranjan says:

Hello sir…what would be batter to have between celestron 80 mm (f-900) & meade 102mm (f-600) for both view celestial & terrestrial. I’m also puzzled with both brands and puzzled also because meade 102 has bigger aperture then celestron 80mm but celestron 80mm has some more magnification then meade 102. is it possible to raise magnification of meade 102 ??…Actually I got this name ‘MEADE’ firstly while celestron, orion like names everyone knows. waiting for u with thanks.

jonathan archer says:

Just now getting back to my lost love… astronomy… I am lown away by the quality of Eyes In The Sky episodes… but I refuse to think this is a non-professional production. The first episode I found explained in detail and pragmatic terms “the equatorial mount”; that was about two weeks ago, now I finally bought my scope (still putting it together) and using Mr. Fuller’s videos to guide and prep me… need to catch the collimation episode.

The point is: we (fledgelings) can be very thankful to have this guy host the web site and put these videos together. He obviously prepares, and cares deeply a out the quality of his products… which we benefit from… anyway enough brown-nosing. Awesome, cery educational. Thank You.

Vedant Pratap Singh Jadon says:

What’s a good telescope for Astrophotography? Nothing too special, just normal moon/planetary or if possible bright galaxies/nebulaes pictures. I already have a DSLR and if I am not wrong I need T-ring and T-adapters to connect it to a telescope, right? Which telescope will suit this purpose the most?

Daniel Wrench says:

hi there, wondering if you could let me know what you think of this telescope – Carson RP-300, 114mm aperture, equatorial mount:  
thanks very much!                       

Goodolboy One says:

Hello, I’m looking to buy a amateur telescope, but being on a very limited budget I can’t afford a real nice one. I’m looking into one that has a price that I can handle, But sense I’m new to all of this, I thought I would ask the experts what they think about the one I below. I’ll give the specs so you’ll know what I’m looking at. Please let me know what you think. Thank you very much for the help…..

Optical design: Reflector

Objective lens diameter: 114mm

Focal length: 1000mm

Highest practical power: 200x

Eyepieces included: Super 10, Super 25, 2x Barlow & 6×30 finderscope

Mount type: Equatorial

Aviation Gamer says:


Chicago Astronomer says:

i work with David in urban Astronomy and I must say…he has raised the bar and now the standard for all astro vids.

Don’t ever stop man….!

The Oscar Report says:

I liked how you explained things in your videos.

Consuelo Althouse says:

Great videos!

Dumitrescu David says:

Hi David,im thinking of buying a orion funscope telescope.What do you think about it?Could i see planets and even deep-sky objects,not only the moon?

txcg1 says:

all my respect for you Eyes on the sky

mardo jack says:

Hi David I am a beginner in astronomy so I bought 70mm eqiutorial mount telescope and lost my counterweight is it ok without it and 70mm good size for planets? and thank you :]

sachithanandam devadoss says:

Is a celestron powerseeker 70az good for looking at planets?

Avery Prosper says:

I was wondering what is the best telescope and eyepeces for 1000$

Eyes on the Sky says:


Alina Aziz says:

This really helped me understand how a reflector and refractor telescope works for my physics test tomorrow! Thank you! Fingers crossed I do well!!

Manu says:

Hey I’m thinking about buying a new telescope, and I have these two options:
A 70mm refractor (f=900mm), that comes with 4, 10 and 25mm eyepieces and a 3x barlow

And a 150mm reflector (f=1200mm), that comes with 10 and 25mm eyepieces.

I think both of these have good prices, but wich one is better to see things like star clusters & nebulae?

kharnak crux says:

well that sure explains a lot.   i’ve mounted a Tasco binocular on a wooden with C clamps.   crude, but effective enough to see jupiter fairly ok.

Cirexin says:

Love it! Thank you!

kanwaljit kaur Dhindsa says:

I can get coma

Eyes on the Sky says:

Hey, thanks for the questions. I don’t do a lot of astrophotography myself, mostly because I”m not very good at it, and it takes way more time (and patience!) than I have most nights. I’d suggest checking with some of the astronomy forums like Cloudy Nights or Stargazers Lounge and ask there. The people who do that more often will have great suggestions based on your needs and budget. Cats can do fine at visualizing faint/small objects, it’s just a matter of working within it’s limitations.

Tom Cannon says:

Hi David,

Watched all your videos as intro.

Thanks for the star chart and resources online. I am must starting out using a Celestron 15 X 70 set of binoculars. I am in Brooksville, FL which I believe is about 28 degrees north. Still having tough time seeing Andromeda but may be just training my eye. Tried using lines from Cassiopeia, etc.

Last night, Feb 11 I was out at just after sunset. Tried Stellarium and a few resources to find out an answer before emailing. In my East and West sky just after the sun dropped down I saw objects one on top of the other on both the East and West horizons. Are these the planets since we are near the Ecliptic? Any help is appreciated.

Tom Cannon

Brooksville, FL​

keepinuhonest says:

You might want to mention in the Cons for Reflectors and Catadioptrics that collimation or alignment of the secondary and primary mirrors is required periodically for best performance. It is not too difficult but not usually required on the Refractor.

HardlineFeminists says:

David Fuller looks alot like Ranger Rick from YouTube channel “NaturalNews,” or whatever his name is, the two are nearly a splitting images of each other. =)

Vanmathi I says:

is Celestron power seeker 127eq is a good buy or starblast 4.5 , I wanted to see both planets and nebulae.please give me some suggestions or tell me some good telescope between 150-200 dollars and the good focal ratio to view both planets and nebulae

Daniel Quirin says:

Refractors, particularly APOs, are undoubtedly the most expensive per inch of aperture. Not Cats.

Marvin Gates says:

Bought a used reflector. Thanks for providing me details of its advantages and disadvantages.

Kyle Culpepper says:

Awesome video series. I would like to post your video on a site I am creating for my class. This is a personal project, with no financial gain. I am simply making a website that is intended to be used by students who are in high school and above. I am an ITED masters student at Valdosta State University. Feel free to check it out. Note: this website is still in its infancy stages of being developed. telescopetypes

Would you be ok with me using your content on my website?

zac says:

Great videos! Really helped me out

 Write a comment


Do you like our videos?
Do you want to see more like that?

Please click below to support us on Facebook!