How to Collimate a Newtonian Telescope │ astrobiscuit tutorial
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- Опубликовано: 31 май 2024
- This is a guide to Collimating Newtonian Telescopes in the daytime using a collimation cap, a Cheshire eyepiece and a laser collimator (I also run through collimating the laser collimator!). I personally use a collimation cap followed by a collimated laser collimator for my daytime collimation. This basic tutorial is all you need to get great collimation of your newtonian or dobsonian telescope. In my follow up tutorial I run though more advanced topics such as how to check if your telescope is mechanically sound as well as running through night time collimation using the stars.
For £3 you can become a patron and access the full 40 minute advanced tutorial here: / 85519443
Recommended Laser Collimator:
UK: www.firstlightoptics.com/othe...
US: bit.ly/3CY6Fnb
EU: www.astroshop.eu/laser-pointe...
00:00 Start
01:52 Collimation theory
04:20 How to adjust the secondary mirror
07:23 How to use a collimation cap
09:25 How to collimate with a Cheshire eyepiece
12:55 How to collimate a laser collimator
15:00 Quick collimation with a laser collimator
the advanced collimation video for Patrons features these additional
How to check if your focuser is pointing straight
Why does the secondary mirror need to be offset?
How to check the secondary mirror is in the correct position
How to check if the weight of your camera is causing your telescope to flex
30:49 Star collimation 
Развлечения
![Collimation of Newton Telescope using [SVBONY] Laser & Cheshire](http://i.ytimg.com/vi/wgIhvsxyB1Y/mqdefault.jpg)
I don’t have a telescope Yet I enjoy these
Get oneeee!!!😊
Same
I don't have one either.... But I do have a gambling problem 🫤
I have a small refractor for beginners but not a newtonian
I just got AWB 130p and IM IN LOVE WITH ASTRONOMY NOW
I honestly thought there was nothing else I could learn about collimation, but this amazing video proved me wrong. You have given me solutions to at least three separate problems I was struggling with when collimating my newts! Thank You for posting THE BEST most easy to understand collimation video I've ever seen! 👌🔥👍
Thank you. That is very rewarding to hear. 👍
Thank you so much, this tutorial is the only one that really clicks for me. That one sentence you said about what the collimated display should look like in the cheshire was a perfect summary for me and I recite that sentence whenever I'm collimating
Some things you should mention: The "basically you fiddle around" can easily take hours if you never did it before, and takes a few minutes if you are familiar with the process. New people should not despair, eventually they will figure it out! If your focuser does not point to the optical axis, and many don't as delivered, you will never get anywhere really, so that is step 1 for new telescopes, as is checking if the donut is actually at the center of the primary mirror. Other than that: Great video! For a long time I used a concenter followed by a laser and recently tried a DIY Ocal-like approach. Given my experience, it was way easier to use and understand, adjusting the focuser went very fast and the result was great. I was skeptical at first, but the experience convinced me to switch.
thx for that good point. Fyi I didn't think that the focuser not pointing at the optical axis merited being in the basic video as most scopes have oversized secondarys which partly compensate for the error. However of course its better to have it squared off so i do run through it in the advanced video and I found a poorly aligned focuser can cause the sensor to be tilted with respect to the mirror and this can potentially make star collimation very difficult. Plenty of free videos about squaring off the focuser out there. feel free to highlight one if you wish. and thx.
I loved the bit where you switched from a Cheshire to a collimated laser. So true, and it's why you can only trust a defocused star test. I tend to use a cheap laser which has been collimated on a V-block to get close, then star test for the final touches. Great explanation Biscuit!
mate much appreciated . you are an inspiration 👍
@@Astrobiscuit Dude! that means a lot coming from you mate :)
Holy cow! I have a 10 inch dobsonian which has been sitting for 12 years.. Your video is great, and I'm feeling better about getting it up and going again. I know the mirrors are very dirty and I'm worried about how to get them properly cleaned, but once I conqure that, I feel very confident that I can collimate it... thank you very much!!
During lockdown i got excited about astronomy and bought a newtonian, spent too much, had a fiddle with the collimation and it never worked again, its been in the attic ever since! I bet theres loads of us lol
Yeh im sure fyi the advanced video takes you thru how to get it back into collimation.... but of course that is only available to patrons for £3 a month which judging by some of the comments makes me the prince of darkness😂
@@AstrobiscuitAll hail the prince of darkness! Does that make you a digestive with plain chocolate on it?
Best collimation tutorial on YT. Thanks.
These Telescopes make my day better....
Astrobiscuit is definitely a good snack
This is vital, especially to those new to Newtonian telescopes which some people may not understand and that this includes Dobsonians. I bought my first Newtonian almost 50 years ago and it took me a long time to understand everything about collimation, back then there was no internet and I didn't belong to an astronomy club. You might want to re-run this video once a year to make certain that it reaches each generation of amateur astronomers, it is that important. I suspect that a great many people simply gave up astronomy because of the lack of knowledge regarding collimating.
This is the best, most informative collimation video on the internet! Well done.
There is no reason that a well made well collimated Newtonian should fall short of any other design , provided the central obstruction doesn't exceed 25% of the aperture. In 1995 I gave a talk on how to accurately collimate a Newtonian telescope. Your video is an excellent example on the subject!
I'm still very new to telescopes and astronomy and the content of this video NEVER even crossed my mind as to why what I'm seeing in the eyepiece could be the reason for blurry or misaligned images... THANK YOU!
Thank you so much for this! You find so many guides on how to use a laser, but your video was the first to explain the simple collimation cap.
You almost let that telescope slide out of the dovetail saddle on your balcony 😅😎 You casually tighten it afterwards. Nice recovery Rory 💪
😂im always thinking about what im saying...
Thank you Riktenstein for the incredible music. It can be calming and then intense. its a piece of art
Thanks so much for this video! I've been struggling with collimation for months now, but this helped me finally complete the job.
Experienced visual observer here. All I use to collimate my Newtonian is an empty 35mm film container with a pin hole in the middle. Works brilliantly 🇦🇺
Your so underrated you deserve 1 million subs
oh mate thanks. Really appreciate it.
This was the collimation video i needed. Absolute legend, thanks a bunch!
You have no idea how much this helped. I thought I ruined my first telescope, but after watching this video everything made sense!! I now have 2 focused telescopes!!!! Thank you sooooo much
awesome. job done. 😁
I love how you described as to these people man you’re saving thousands of dollars you know that right I hope they kick you five bucks a month
Very cool that you made an episode for your rookie viewers !
Thank you very much, very interesting and helpful presentation.
FANTASTIC vid, Breaker! This one came out of nowhere and super glad it did. 'biscuit FTW!
😂
Very instructive - thanks, Astrobiscuit.
Being relatively new to astrophotography and only having used refractors before, colomation has always put me off newts but this easy guide is amazing and takes most of the fear away! Good job as always biscuit!
ah thx bud
Great explanation and vid, thanks.
EXCELLENT VIDEO!! Don't forget to keep the ota horizontal while adjusting the secondary mirror. This assures you won't accidentally drop a tool down the tube onto the primary mirror.
yes very true
a concenter eyepiece such a good tool for getting the secondary positioned to the focuser accurately , you can also use a camera with software. good for dailing out any small errors for imaging .
الحلقة اللي كنت بإنتضارها 👏
OMG... I remember seeing your channel with just a few thousand subscribers and I remember thinking "astrobiscuit" is such a perfect name for a channel. And look at your sub count now lol 😂 well done man!
One of my first jobs delivered the money to buy me a telescope. The cheapest I could find. That night I was amazed at how fast the moon traveled out of view. The knobs to track didn't seem to work. It wobbled like the gear axles weren't dead center. There was a manual, but in a language I didn't understand. And the internet, or even BBS was not yet a thing.
It was nice to see the moon up close, but with the biggest magnification, there were blue and pink lines contouring the moon. It took only a few weeks to get that disappointed I threw the telescope in the attic.
It came down very few times. and somewhere in the 40 years following it got lost.
So, now I see what went wrong, and it's not the "precision instrument you should *not* fiddle with" I thought it was.
What perfect finding😂😂 I just got my 8inch dob last week
Hello finally back
Well done mate
Astrobiscuit my savior
Nice tutorial. keep it up
very nice, thanks my friend.
Thank you for recommending a good laser collimator. I was losing my mind with the horrible one I bought off Amazon and had no idea why I couldn't get it collimated.
OMG - I just changed my focuser and have been going MAD trying to get it to a point where I'm satisfied I've done it right. I hope this helps.
im afraid thats in the advanced section. just look up using a laser collimator to check your focuser us pointing straight.
Nice tutorial
Whilst collimating my GSO F5 newt, I noticed that the secondary mirror holder has indentations for the 3 screws, so you can't rotate it as you suggest. I've had this scope a few years and over time the collimation screws have ended up almost screwed all the way in and I realised that backing them way off, allowed me to tighten the centre screw which moves the mirror closer to the open end. This simple adjustment has made all the difference, the secondary is now positioned directly under the focuser.
Finally the real tutorial
Fantastic video! One thing you might want to do is have a disclosure warning when looking thru a mirror with a laser pointed and looking right at it as precaution :D
true... Ive actually caught the laser. I wonder if they're designed to be not TOO dangerous. Hope so.
If you've never tried it, check out barlowed laser collimation. It's easy, doesn't cost anything if you've already got the laser and a barlow lens, and it eliminates a lot of the misalignment errors that are inevitable in a telescope.
Thanks, bro
Dont have a telescope, yet I found your explanations of the mechanics and techniques very interesting! Brilliant video as always!
wow... that is suprising. i feel you must be a true nerd at heart. 🤣
Collimating my 8 inch Newtonian has been the bane of my existence. I have a few laser collimators, but one of my challenges is that either the laser collimators are not collimated, or the focuser tube is not flat. If I spin the laser in the focuser, the red dot on the primary spins round and round with a radius of about a half inch (just as you showed in the video), I guess my next step is to build the laser collimator colllimator!
that means your laser collimator needs collimating... see the rig i use in the video. The focuser may be fine... there is a different check for that.
8:08 the primary mirror end of that particular Newt looks pretty damn steampunk.
I colimate my Newton with my laser every time I set it up for photography. The 5 minutes are really worth it.
What would you get for dso's(assuming you have a dslr and a good tracking mount)
A 6 inch f5 newt or a 6 inch rc ?
For everyone using a laser collimator: Check the laser class! It can cause damage to the eyes!
yup, people really shouldn't be touching something stronger than a Class II imho unless they really need the power or are laser enthusiasts.
@@xander1052 I was somewhat shocked when I noticed mine has class 3.....
thanks
But i cant see clearly the hair cross of the chesire my eyepiece its maybe too short i bought the short version of the chesire ( cheapest) my eye can't focus the cross and what is the correct position to see trough the hole?.
Cool. A real-life mad scientist 👍
I love your videos. It inspired me to begin astronomy and buy my first skywatcher dobsonian 200/1200
Wow im early, and this video is relevent, hi astrobiscuit
hi
I'm further reminded why I don't use Newtonians :). Clears skies!
😂
Love your videos, when's the next due?
Great video but i have a question. People in the discord server are saying the laser is bad, should i listen and just buy the cheshire eyepiece or buy a collimation cap and laser collimator?
I'm sorry, but that thumbnail is just amazing 😂
Very solid focuser you have, any models that would be good to retrofit to scopes with sticky wobbly focusers??!!
baader diamond steeltrack seems v good. Its hard to find any for small 6inch newts tho
Hi Rory, I know this probably sounds like a dumb question, but how do you become a patreon member. I don't know what to click or where. I'd like to watch the rest of the video about star collimation. Thanks in advance
thanks for this, have you also worked with starSense explorer? I recently got the Starsense explorer dx5 sct and I'm super with that app.
yes its good...
Bedankt
Thank you😁
Hey astrobiscuit I have a newtonian but when I take pictures the middle is really dark circle like possibly the shadow of secondary mirror is that normal? Or something wrong BTW there are no light leaks
Look up vignette this can cause what you describe. BBC sky at night web site has a piece on it. ‘What is vignetting?’ was my search term. Hope you get it sorted.
thank's
Hi, I've got a question that's been on my mind for some time now. Are there any off-Axis Newtonian telescopes like the ones in this video? How expensive would they be? How complicated it would be to make one of them professionally (if they exist) and maybe DIY version? And would that remove the spikes in the images of bright stars? (I've always wondered if the spikes could be removes in a non-digital manner and what would that image actually look like.)
I've thought about this too and ive not seen any available commercially
The Hershillian reflector is perhaps the most obvious type. The most common way we see this is with a typical household satellite dish. Optically it’s very hard to do and get anywhere near the consistency needed across a small mirror let alone a mirror of the size for a telescope. Those off axis mirrors are available but in smaller sizes and become very expensive beyond a couple of inches.
However some segmented designs of reflectors have all their mirrors except for the centre one as off axis mirrors. Main example is the James Webb. Unfortunately each single mirror wasn’t exactly affordable. I did ask someone who is a very well known guru on figuring mirrors on the chances of of this being feasible for an amateur telescope. The answer was preceded with some drawing of breath and wincing.
Great video! Is that a Televue case you have there? I wonder what marvelous piece of optics is in there 🤤
an old np101 with a bit if fungus on the lens😭
Please do review on reflector telescope svbony sv 501p 70/400 please 🥺
I've found my problems were with the secondary . Once I learned how to aline the secondary mirrors life became better😊
Hey, I’m really interested in the full lenght video but i don’t want to deal with patreon. Is there any way i could just buy the video?
sorry i uploaded the video to patreon so there is no easy way but if lots of folks request the same thing then I'll try and sort something out...
Alright, I will sign up then , don’t bother
the moment a paywall appears the content stops being so relevant and attractive, there are many free sources of info, and that's how a yt channel dies.
well im glad i now know how to pay my morgage.😂😂😂😂😂 but seriously youve got 16 mins of well explained newtonian collimation advice for free why are you complaining?
@@Astrobiscuit well i'm not complaining honestly, just gaving you some advice for free!
Maybe a dumb question.
Is it possible to make a camera in the front of a newtonian scoop?
Instead of the secondary mirror.
I understand maybe problems with distance.
With a bit engineering with 3d printed parts i think it's possible or is it out of question?
Because of the main mirror.
I hope it's possible for real.
yes it's possible. People have even done it before.
Technically? Yes. But you'd be introducing more elements into the light path. Depending on what type of camera you use, you'll block more of the incoming light. Especially with a DSLR, which due to its shape will also block the light in an irregular pattern. So you'd have to use a smaller circular camera such as a dedicated astro camera. Also, you can't use filter wheels with your camera, since the filter wheel assembly would also sit in your light path, so there's that limitation as well.
Still, let's say you go with the bare astro camera. Now you have the cable coming off the camera that will asymmetrically block the incoming light. Why is this a problem? Well, on a standard Newtonian, the secondary mirror is held by spider vanes that are as thin as possible, in order to distort as little as possible. Yet we still see their effect on the stars. The crosses around stars that you see in astrophotos are diffraction spikes caused by the vanes; look up "spider vane diffraction spikes" for an explanation. So now imagine what an extra USB cable, which is a lot thicker than your typical spider vane, will do to your view.
Now, there is a telescope design that keeps everything in-line, but solves the problem differently. The various catadioptric designs like the Schmidt-Cassegrain, Maksutov-Cassegrain etc. have a glass disc in front through which the light enters. It then hits the primary mirror in the back, which focuses the light and sends it forwards. There it hits a secondary mirror that's stuck to the inside of the glass (or a mirrored section in the center of the glass), which throws the light back again towards the back of the telescope. Finally it goes through a center hole in the primary mirror, and exits out the rear of the telescope, where the focuser sits. You can use whatever camera you want, since it sits behind the telescope, and does not block the incoming light. There are no diffracion spikes because there are no spider vanes holding the secondary in place. Finally, compared to refractor (with lenses) or Newtonian telescopes, these designs are shorter for the same focal length (magnification), which makes them more compact and reduces their weight. This makes them easier to transport to a remote dark site.
yes... and if you're camera is small its a good idea but you'll need a longer tube.
It's called a hyperstar.
Hi, I have an honest question, I noticed Cassegrain scopes have a glass front with the secondary mirror, I was wondering how come Newtonians dont use the same glass front with their angled mirrors? seams like it would solve the diffraction spikes?
optically flat windows cost more than the scope itself but they are quite good i think and help with thermals as well as diffraction spikes....
@@Astrobiscuit Thank you, I appreciate your reply and time.
There are Schmidt-Newtonian scopes, but looks like they aren't in production any more:(
This is a random question but is there a way to computerize or atleast motorize a telescope without spending over €100 and if yes can you pls make a vid on it
great
It's a good idea for secondary collimation to have three Allen keys, one for each screw. That way you don't have to keep moving one key around.
That’s a good idea. I’m looking at replacing mine with knurled head screws so I can just use my fingers.
I don’t understand when we need to collimate for the secondary mirror. I only make a simple collimation to the primary mirror using Polaris but I have never done anything to my primary mirror yet. So far I have no complaints but maybe I should?
if your star test is fine then leave it and be happy👍
@@Astrobiscuit that is good news for me. It means I will be checking this video later someday :)
How often do you have to colimate the laser?
And I wonder how hard it would be to put a decent CMOS sensor in place of the secondary? Advantages: 1.brighter image due to no 2nd mirror loss, 2. No distortion from 2nd mirror, 3 no camera flex on the ota, 4. Potential passive sensor cooling as it could use the cooling of exposure to the night sky via heat sink or similar. Disadvantages: 1.possible heat distortion? 2. Wiring ribbon or equivalent needed for PSU & signal. 3. Collimation issues due to thermal expansion of sensor holder?
PS. Love the video as always :)
my laser has stayed collimated for about a year now.... good luck building the newt with no secondary. I have thought aboht it.
This very thorough instructional video has put me off buying a Newtonian purely because I don't have the patience that you obviously need to keep the telescope functioning properly. Aren't there more compact versions (cassegrain?) that stay in line?
yep refractor is what you need.
Is collimation less of a problem if you're into visual astronomy instead of astrophotography? I mean, would a simple collimation cap suffice for visual astronomy?
most visual scopes are f6 or 8 so yes a collimation cap is fine... and a quick check with an out if focus star would get you very good collimation but if your scope is f5 or less then maybe you want more. Ultimately star collimatiin is thr best and collimation is very important for planetary observation.
@@Astrobiscuit Great! Thanks for the reply. I'm going to build a 6-inch f8 scope soon and collimation is a bit scary. I'll definitely come back to this video
Yes, those 3 screws MUST be adjusted to center the secondary under the focuser, otherwise you’ll get uneven field illumination. A laser isn’t enough to collimate the primary, the tolerances are well below fractions of a milimiter therefore unless the laser is barlowed it shouldn’t be used for the primary
I dont agree with everything you say. I think you need to check you fully understand secondary mirror offset.
I must admit ive no idea why folks barlow their laser. Perhaps you could enlighten me. I see no advantage over a well collimated regular laser...
@@Astrobiscuit I do understand secondary offset, it offsets the secondary holder toward the primary and away from the focuser, intercepting the entire light cone of the primary allowing even field illumination.
Anyways those 3 screws have nothing to do with offset, they are meant to center the secondary under the focuser, opticians know what the do, they haven’t installed the 3 screws to annoy us…
The barlowed laser simply magnifies the laser spot on the target so it’s easier to read any miscollimation
Sir I cant afford a good telescope yet I have a mini one could u find me a way for getting a big one
The correct way to collimate the secondary mirror is to block the primary with a sheet of paper/card and place a sheet of coloured paper opposite the focuser. This allows for the secondary to be seen clearly. Position the secondary mirror so that it's perfectly centered in the focuser drawtube and perfectly round. Easily checked and confirmed by a concenter. Then and only then do you adjust the primary.
im afraid i don't think centering the secondary is a great thing to do in a fast newt. Fine for f5 ot six but i think an f4 newt the secondary should be pushed slightly forward towards the primary mirror by the secondary diameter / (4xfocal ratio) This is quite advanced though so i don't cover it in this basic tutorial.
@@AstrobiscuitAgreed 👍, however there's no standard placement for the secondary offset in fast newtonians. The offset is entirely dependent on the manufacturers design which should be easily confirmed.
what you think about Concenter Collimation Eyepieces?
well i personally dont centre my secondary in the focuser tube but for thosee who do they are fine if a little pricey.
@@Astrobiscuitthanks. I've always had problems with secondary mirror.
Is it about cause i had question about colimation on your discord server ?? If its, than thanks man for tutorial.. very appreciate.. thanks for your work..
well not just you... its something ive been strugglong with for years and niw i feel like i have a good understanding i thought I'd make the video.
May I just remind my dear viewers that without patrons I wouldn't be able to make any videos. So I have made a longer advanced video as a way of thanking my patrons and as a way of gaining more patrons. If you don't think this is fair on those without the funds to become my patron then please post what you consider to be the best free newtonian collimation video below. I happen to think there is a lot of misinformation out there but I'm happy to support fellow youtubers who get it right. The video should include aligning the focuser, secondary mirror offset and how to check it, testing to see if your focuser can handle the weight of your camera and of course a good method of star collimation as those are the most important topics in my advanced video...
How about primary mirror without adjust screew?
well then you have to hope its pointing straight... and if it is you're ok.
I'm not interested in the topic as much as the others. I don't have a telescope. I just come for the enthusiasm. I press like before the video starts.
AH..... this video would`ve been soo handy for me 25 years ago lol :D
me too😂
Need to collimate a f4 newt? Get a catseye collimator kit.
Purfect collimation every time.
star collimation is still best as it'll account for things like camera sensor tilt.
man, now I want to get a telescope
Make more content biscuit
Your videos weren't being recommended until I manually entered your channel name. Just a heads up
hmmmn...
When one promotes more content behind a paywall youtube doesn't promote the channel
👍
IM COLLUMATING MA LAZOR!
جميل جدا
1 Frac and 1 Mak, no need for this stuff. However, love watching his vids for his London accent and (some) comical moments 😁