How To Use An EQ Telescope

hey everyone john reed here from learn to stargaze and author of the new book 110 things to see with a telescope in this video we're going to learn how to use an equatorially mounted telescope for basic visual astronomy after we show you how to use this equatorially mounted telescope will go to a nearby field and let random people use it and see how they do this is learn to stargaze [Music] if you've just received a telescope that looks like this you're probably wondering how to use it and this video is for you if you're wondering if you should buy a telescope that looks like this consider this if you ask a seasoned astronomer what type of telescope to buy they'll probably recommend a dobsonian why because dubsonians are effortless to use and you can easily see lots of cool stuff there are many different models of dubsonians at pretty much every price point not many seasoned astronomers would recommend a sub 200 equatorially mounted telescope like this to a beginner and this is pretty much any telescope with eq in the name that said because this telescope looks like how people believe a telescope should look this telescope along with the 127 millimeter newtonian version is extremely popular and based on feedback i've gotten from viewers in countries outside the us and canada this might be the only model of telescope available to them and just because seasoned astronomers don't recommend it that doesn't mean if you have it you can't enjoy it there are lots of people that love their small telescopes on equatorial mounts the reason this design exists at all is that it gives the observer the ability to track objects across the sky but why does this even matter well as the earth turns on its axes the entire sky appears to rotate this means that unless a telescope is motorized when you look through the eyepiece you'll see the objects move across your field of view equatorial telescopes are designed so that after you've found your target you simply turn this knob that's the right ascension knob to offset the earth's rotation thus keeping your target within the field of view i actually found this extremely helpful when doing a lunar observation program that required me to keep the moon in my field of view for long periods of time so that i could sketch what i was seeing so if you're drawing or sketching things that you see in space things that require you to stay on an object for a long period of time and you want to do this without a computerized telescope without a motorized mount an equatorial telescope might be for you back before computerized telescopes eq scopes were also used to locate objects in the night sky this was based on objects declination and right ascension those are coordinates equivalent to latitude and longitude that's what these dials here on the telescope were used for although it's possible to locate objects using this method it is very difficult rarely done and beyond the scope of this video so i've assumed you follow the assembly instructions correctly and the telescope is ready to go let's quickly go over some of the parts of this telescope that are unique to those on an equatorial mount first you have the altitude knobs these allow the telescope to go up and down then you have an azimuth knob which when loosened allows the telescope to move left and right fancier telescopes have fine adjustment knobs for this axis as well note that these knobs are only used during the alignment process not while observing or looking for targets next we have the right ascension axis this moves the telescope around the celestial poles or if you're in the northern hemisphere the north star the lock for this axis is here generally this axis is loose when looking for targets and locked while observing then we have the declination axis this moves the telescope toward and away from the celestial pole or if you're in the northern hemisphere to wart and away from the north star this axis is loose while looking for targets and locked while observing and these are the slow motion controls one for declination and one for right ascension these are generally used after you've found your target for centering and for fine adjustments the right ascension control or ra control is used to keep the object you are observing within the field of view now it's time to start using the telescope the first thing we're going to do is balance the telescope and this can be done during the day we're going to start with the ra or right ascension axis so with the axes loose we're going to move this counterweight until the telescope stays where you put it there we go and again this is the declination axis to balance this we make sure that the lock is loosened and we balance the declination axis by sliding the telescope up and down within the tube until it stays where we put it when the telescope is balanced we'll re-tighten these two nuts here but we need to keep it loose enough so that you can still turn the telescope within the mount then return the telescope to the home position and lock that axis now we're going to check the alignment between the finder and the telescope this is the finder scope that came with the telescope i recommend replacing this with a red dot finder red dot finders are much easier to use for finding targets in the sky but we're going to work with what we've got this is another task that's best done during the day i usually use a distant chimney basically you find the chimney in your telescope and use these three screws here to then center the chimney in the finder scope then you move back and forth between the eyepiece and the finder to make sure that the chimney is centered in both if you're doing this at night you would center the telescope on a bright star or a planet and then make sure that the planet or star is centered in the eyepiece and the finder all right now the most important part of using an equatorially mounted telescope polar alignment let's start with making sure the telescope is on level ground don't set it up on the deck that'll be too wobbly i live in the northern hemisphere so my goal right now is to point the right ascension axis directly at the north celestial pole now the north star is pretty close to the north celestial pole so my goal will be to simply point the telescope at the north star while in the home position the first thing we're going to do is set our latitude now if you don't know your latitude just ask your phone hey siri what's the latitude of halifax nova scotia once you have your latitude turn these knobs here until this dial matches your latitude the second thing we need to do is make sure your telescope is pointed north to get started i often open the compass app on my phone and place it alongside the telescope rotating the mount either left and right until the telescope is pointed north now i can't actually see the north star from my backyard because it's hiding behind a giant tree so setting the latitude and pointing the scope north is generally good enough for me but if you can see the north star it helps to do the following for more precision you can find the north star using the pointer stars in the big dipper like this so what you're going to have to do is try to get the north star in your finderscope then you're going to make fine adjustments to the altitude of your telescope and the azimuth that's the left right direction until the north star is centered in your finderscope for even more precision center the north star in your eyepiece this is also a good time to check the focus of your telescope before moving on to your first target to set the focus get a bright star and adjust the focusing knob here until the star is as small as you can make it now that the telescope is polar aligned it's time to find our first target the most important thing right now is that the mount itself should not move if this for some reason gets moved you'll have to start the polar align process over and if you're new to telescopes your first target should probably be the moon or a bright planet like jupiter now i always recommend starting with your lowest powered eyepiece that's the one with the highest focal length listed on the side of the eyepiece only switch to a higher powered eyepiece after you're centered on your target and leave barlows off a barlow is the thing you stick between the eyepiece and the telescope to increase the magnification you only use a barlow when zooming in on the moon and planet searching for a target with the barlow in place is extremely difficult so leave it off most of the time in fact you might even put it away in a drawer and when you're ready to move beyond the moon and planets it helps to have a guidebook like 110 things to see with a telescope or 50 things to see with the telescope kids these books are organized by season so there's always something easy to see in your night sky so assuming the moon is over here in the west we're going to loosen the right ascension and declination axis we're going to pivot the telescope over toward the moon we're going to rotate the telescope tube so that the eyepiece is in a comfortable position and we're going to center the moon and the finder scope will then lock the declination and right ascension axis now we can use the right ascension and declination slow motion controls to center the moon in the eyepiece with the moon centered in the eyepiece you can begin to make your observations remember to turn the right ascension knob to keep the moon centered in the field of view the right ascension knob can be moved from one side of the telescope to the other whichever is more comfortable for you if you enjoy observing the moon be sure to pick up a copy of 50 things to see on the moon which will help you identify and appreciate the lunar features like prominent craters and lunar seas alright let's wait until dark go to a nearby park and see how intuitive or non-intuitive this mount really is so what's your name annette your name is annette okay can you use this telescope to find the moon as soon as you're close you're gonna lock okay the axis like this and this yep you got it yep all right good job high five okay so what's your name me okay the challenge is can you use this telescope to find the moon i hope so here's here's a here's a hint though you might want to start with the finders with this one first oh yeah wait almost okay so what we're gonna i'm gonna give you another hit right there perfect you got it okay so we're gonna lock we're going to lock these axes here just twisting it right it's still there you got it nope nope oh can you find it isaac oh okay wait this is different we had a little help from seven-year-old yeah that's true all right isaac this is what i found well i hope you enjoy this video on using an equatorially mounted telescope please subscribe to learn to stargaze so you don't miss any future videos and let me know in the comments if you have any of my books i love the feedback and remember the future is looking up

Channel: LearnToStargaze

Views: 90,216

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Id: Ks3ReGgFhwY

Length: 11min 35sec (695 seconds)

Published: Thu Nov 18 2021