Align equatorial mount when unable to see pole star (north or south)

salutations celestial sight seers i'm david fuller  with eyes on the sky 10 years ago i did a video   for the very first time on youtube and it was how  to align an equatorial mount and while that video   is still accurate i have gotten a lot of questions  over the years about how to aim the telescope   at the celestial pole without having to be able  to see the celestial pole so if you either can't   see polaris in the northern hemisphere or if  you're in the southern hemisphere and you are   trying to align towards sigma  octans which is a very dim star   it's only fifth magnitude then how do you do that  or what if you have a tree in the way - NOOOO! -   or a building or some other structure where  you're unable to be able to physically see   where the celestial pole is at so this video is  designed to help you do that and do it quickly so here's how we kind of start with that you do  need one piece of equipment and that's going to   be a decent compass and what the compass is  going to be able to do it's going to help you   set the telescope in the right direction and  we'll kind of need to do sort of two things   at once we're going to need to both level the  telescope as well as align it so you might have   to do a little bit of one and the other but we'll  start by aiming this you can see i am actually on   uneven ground here so we need to make sure that  we're adjusting our legs to accurately get things   set up now one thing about a compass when  you're using it near something like iron   the problem is is that it can mess up the compass  and cause it to give an inaccurate reading so what   i do is i just use a little piece of wood and  then you can hold that right on there and then   parallel and you're going to get a much better  reading now i'm not anywhere close to being north   uh north is kind of this way from  where i'm at so what we want to do   is have the counterweights facing towards the  north so i'm literally just going to pick up   the mount and spin it around because on this  particular mount i cannot actually spin it uh   very far it's just got a limited movement to be  able to do that so we'll get this all set up there   and that's pretty close it's not dead on but it's  close enough that i'll be able to use the fine   adjustment so now what i want to do is actually  level the telescope and there's a bubble level on   this particular mount so that helps me to level it  if you don't have that there's a couple different   ways you can do that one is you can use a plumb  line which is just a weight with a string on it   and you can actually hold that right underneath  the center of the telescope here and have it drop   down right in the middle of where your tray is  and if that's centered then you'll be all set and just like that i've got a good  level with my bubble level here we need to make sure that we are aimed in the  correct direction so i'm gonna pull these open   like this give myself plenty of room that way  i can spin the mount like this i'll bring my   compass back out now the thing that you need to  know about a compass is that magnetic north is not   the same as true north so while i have this aimed  directly at magnetic north right now my actual   location from where i am is about four degrees  off of true north so i need to adjust for that   and then i can use these to even refine that  just a little bit further if i need to and then   also lock it into place so that it won't move  during my observing or astrophotography session   and that's pretty good that  has me at magnetic north   that i have adjusted where my actual north is you  can see this is a really good compass because it   allows me to move this and has a nice sharp line  right there showing where i'm at and i'm four   degrees off of north so when it aims north on the  compass itself i can account and adjust for that so that gets me at true north now i need to  look at what my actual latitude is so we can   find that with a simple google search or using  your favorite search engine to find out what your   actual latitude is you want to get that within a  degree is really going to be ideal most telescope   mounts only provide at best about every two  degrees and with this particular telescope   you can even see the arrow is a flat looking arrow  from how it was actually uh made when it was cast   so that's not terribly accurate necessarily  so in order to adjust that we want to take   our slow motions here and you can  see i can move this down this way   if i was closer towards the equator i would be  able to move it this direction so with this i'm   you know closer to like 32 degrees and then if we  want to crank that up we can move that up as well   uh if you happen to be in either the northern part  of the united states or in canada or even in the   united kingdom then you would want this quite a  bit further and it would need to be more like this   up more towards maybe 50 or 55  or even if you're north of there   you can bring that all the way up as well so i'm  at 41 degrees north latitude so what i want to do   is try to look at this and get it as close as  i possibly can because i know i'm facing north   so if i get it as close as i can to that 41  and that's going to put me right between the   40 and the 42 mark that should be pretty close  and then i want to lock this one on this side   and now i'm locked here so i cannot  move left to right relative to what the   celestial pole is and now i also have my  latitude correct because the latitude that   i have this set at is going to be parallel  to the axis of the earth how it rotates so   when you're parallel with that then you can turn  your telescope in right ascension and declination   and then it will follow the stars depending on  which direction that you have your telescope   pointed now you can see that this is not  balanced so that's what we're going to do next so this is really really off and the reason why  you want to balance the telescope is because it's   helpful to be able to unlock those clutches this  is your right ascension clutch because that's that   axis right here that aims towards the pole  and in declination you want to be able to   aim the telescope whatever you want to try  to look at without having to touch it because   you're going to want to be able to move that  mount to aim precisely at what you want to see   and then once you've done that you will be able to  then re-lock the clutches engage your motor drives   and then have your mount automatically track  the night sky not every mount has the automatic   motor drive some of them may just have a slow  motion control and even if that's the case   then really you just follow the sky just  by slowly turning that so let's see how   our balance is so if we remove this that's  still a little off so i need to move that up   and that looks pretty good in right ascension  so that's not going to move at all now you know   it may have noticed that i actually go ahead and  mark these because it's so much easier in the dark   to have even just a simple knowing which right  ascension and which one goes to declination you   don't need to mark both but even just one then  you know that the other one goes into the other   location so we also need to get ourselves set  in declination now for this particular telescope   i'm at a bit of a disadvantage and i need  to change this somewhat because even though   this looks like it's balanced it actually is a  little bit tail heavy and i also need to still   put a star diagonal and an eyepiece on there  so that's really going to make it heavy on   that end because i also have a finder scope  there but i can't move this any further so   i actually need a longer dovetail mount that i  can move this further back this direction so i   can balance the telescope more because i've run  out of space to be able to lock this into place   so once we have that all set then  we can lock everything into place and then you will be aligned at the  celestial pole and then you'll be able to   aim the mount wherever you want to go so if  you want to look at something that's towards   the celestial pole you can do this if you want  something that's maybe more towards the celestial   equator you do this now if you're going on that  side of the sky don't do this you don't want your   counterweight up do a meridian flip flip it around  and then aim it that way and it's just as simple   as that and that's how you align an equatorial  mount without having to see the celestial pole   and then you're all set to be able to observe the  sky and only have to turn it in one direction for   an axis or turn on the motor drive and let it go i  want to thank you for checking out this video and   sticking with me for the last 10 years i've  been making videos on how to find all kinds   of amazing things in the night sky we've looked  at solar eclipses we've looked at lunar eclipses   we've looked at comets we've seen all the planets  including pluto yes pluto you're still a planet   we've looked at all kinds of deep sky objects  and double stars and a lot of amazing things to   be able to see in the night sky and i hope you'll  continue that journey with me i'll keep helping   you find amazing things and i'll help you learn  how to use your equipment to the maximum potential   so that you can see that too thanks for watching  i'm david fuller wishing you clear and dark skies NOOOO! um..   what are you doing? what? are you trying  to see the stars in the moon better? yes. maybe try something different  you have the hedge trimmers

Channel: Eyes on the Sky

Views: 54,680

Keywords: Eyes on the Sky, David Fuller, Amateur Astronomy, Beginner, Newbie, How-to, How to set up a telescope, Equatorial mount, How to align a telescope

Id: iJueYgDbeyQ

Length: 10min 49sec (649 seconds)

Published: Mon Nov 30 2020