I loved your observation where you said that a telescope is like a musical instrument that needs to be tuned from time to time. Fantastic!

This is by far the best and simplest collimation tutorial. Fantastic!!! I will do mine next time I dig out my newtonian scope.

Well, 4 years later and you helped me realize that the circles with the look of small secondary mirrors all over my screen was actually stars. All I had to do was fine focus and I would have been good. Thanks! Also me from the future, you are going to love the new Astro cameras! lol!

As a sanity check, after star collimating like this I will often "flip" the defocus to the opposite one (if I was in-focused, I switch to about the same amount of defocus in the out direction) and make sure things still look good there. Certain other alignment errors (like a titled focuser or secondary) can show up by the in and out focus exhibiting different skews to the pattern, so it's helpful as a quick verification that you don't have to do deeper investigation of a more complex problem than primary collimation while you're in the field.

Perfect timing, this is the one video that doesnt need a laser collimator. Thank you so much!

This was by far the best video explanation I have seen! Instantly subscribed, and thank you

Just wanted to say that this is the best video I've seen on using the airy disk collimation. Thank you for producing it

Chris - this video was by far the best demonstration of how to collimate my SCT. Last night I spent about 60 minutes trying to apply what was written in many blogs - it was excruciatingly painful. Had I seen this video, would have been done in less than 10 minutes. The SharpCap aiming and crosshair tip will be used again - would have taken me a while to connect this feature to make collimating a lot easier. Given this video, will be subscribing to your channel.

Its always a good idea to “touch up” or verify your finders after doing collimation. If you had to do adjustments it will change some.

amazing!! simple and useful, thanks🤟🖖

Clear instruction and demonstration. A great help, thanks.

Very helpful! Thank you for putting this together!

I wasn't sure this was achieveable with a newtonian, but only a SCT. So glad I ran into this video, cause my 10 " Starfinder is a real challenge when collimating. Also, the analogy of a music instrument in comparison was spot on. Thank you so much for such great content.

What a great analogy tuning your instrument!

This is awesome! Thank you!

Please forgive me if that sounded rude. I appreciate your channel and indeed everyone who tackles this hobby and shares their experience. Clear skies. 🙂

Thanks for the tips, I use this method to check my results and it works great. I collimate by looking through the eyepiece holder (without an eyepiece) and adjusted the secondary and primary mirror until they are all visually concentric to collimate. Checking by aligning with a star (as shown) and it's spot on. I do have a laser collimator but the laser is almost off the target entirely when the collimation is perfectly fine. Laser collimators are basically useless and it's much better to put that money towards an upgraded eyepiece or a moon filter.

I think this is possibly the most informative video about collimating using a star that there is. Thank you

Amazing advice. Will try this out👍

That was a great help, thankyou!!

Nice tutorial. Thanks for posting that.

Good tutorial! very nice explained!

Great video- thanks!

Great video, thanks! I don’t have a high magnification lens, will a Barlow work to get the diffraction rings?

Great video! Thx so much!

STAR COLLIMATION. NOT TO BE CONFUSED WITH A STAR TEST. For a star test,(which is the best test for collimation), you need to use a high magnification eyepiece between your camera and the telescope. That's the only way to get a true airy disc with concentric circles which indicate the direction of the mirror misalignment. This method is only good for centering the secondary mirror in front of the primary mirror. It may be possible to use a barlow in front of the camera to do a STAR TEST, or just do it visually through a high power eyepiece.

Thanks for this!

I have a wifi controlled slewing mechanism through an app with my mount. Sometimes slewing through the app can be a pain. I think I'm going to stick with my laser collimation, but this was interesting. Good video.

Thank you!

Thanks. Just subscribed.

Very useful tutorial I just got a 150pds myself.👍

Just subbed thank you👍🏻

Very helpful video, thanks for sharing your knowledge. It's a real benefit to us just getting started. Did I miss what magnification you were using to make this ideal for defocus? Is 130X enough?

Thank you 🙏🏻

Great vid Chris, thanks for posting this! Since a fast newtonian (f4 or faster) can easily lose its collimation during the night (eg temperature change, steel tube shifting etc), I'm scratching my head for the most easy but accurate way to confirm my collimation periodically during live EAA sessions via ASI294/sharpcap..... When visual, is easy to do a conventional star test with a high enough magnification eyepiece and a slightly defocused star in order to see the airy disc pattern and conclude from there..... Is there a way to do the same and see the airy disc of a star using sharpcap? Must be way more accurate but I guess can not done due to lack of enough magnification, right? In any case, your method seems accurate enough and pretty simple for sure

Just got my 8" Dobsonian, and I dont have a laser, so I'll try this out whenever i get a clear sky!

Greetings from Vancouver, Canada! Thank you for this. Collimated my 8" dob for the first time and I think everything went well. Quick question; other resources I've found online references concentric circles but when I attempted collimation my view was similar to yours with the secondary mirror and spider veins and I couldn't really see circles...I assume everything's all good? Thanks!

Hallo Chris. Frohes neues! Du justiert in deinem Video den Fangspiegel genau in die Mitte, aber was ist denn mit dem offset mit dem der Fangspiegel montiert ist? Dadurch wirkt er doch auch außer mittig oder nicht? LG Kevin

Hello Chris, thanks for te grwat video. It's explains exactly what i loooked for. But there is a question left:

Hello, I just subscribed to your channel and saw your latest moon video! Could you do this in a very dark room with a very small light? Thanks again for the tutorials and videos.

Hey, thank you for this. I have some problems with a bushnell northstar and will try this. Just one question: how do you see when/where to collimate the secundary mirror to?

Hi. Do you defocus in or out? And is there a method to collimate secondary mirror with this technique? Thanks

You need more subscribers

thank you for this video that I didn't know, only looking at French websites, I found it thanks to the search engine ! ....In fact, you only act on the primary and never on the secondary, as far as I can see?...and this setting is enough to have a good collimation

I pulled my Newtonian out of storage and immedietly threw it on the stand and attempted to start viewing things (it had been YEARS). Then a few minutes in, mind boggled why i couldnt see a single thing with any lens or focus... i noticed the half inch thick dust layer on my primary mirror 😂

Help please good video but done everthing with a lazer same result nearly as yours but all i see now is the secondary mirror nothing else no sky moon planets stars etc so what have i done wrong ???

How much should we unloosen the locking screws and should they all be loosened before a collimation screw is manipulated. If finally it is not possible to move the black circle to the Center can I instead try the 3 screws to do this on the Secondary mirror?

in a F4 newton, shouldn't the shadow of the secondary be decentralized?

I wonder if there is more involved with a fast newtonian that has the "offset" of the secondary mirror...

So what if the star donut shape is symmetrical when you rack you focus out beyond focus, but oblong and misshapen when you rack in past focus? Does it need to be symmetrical in both directions? This is the issue I've had when trying to use this method. The collimation looks good on one side of the focal plane but not the other.

Oh so I CAN COLLIMATE LIKE THIS? Oh man... Maybe I wont center spot my reflector now if this works out. I know my DSLR attached without any barlows can focus in a way that creates this effect where I see the shadow of the reflectors clearly. With center live view zoom I can even check if it is centered by zooming in on the camera. There are distant strong streetlights out my window I may be able to use (I use them to calibrate my finder and they perfectly calibrate even that. Pretty far away). Emediete thumbs up! So far Ive been able to do neat collimations by looking into a barlow without eyepice (It has this effect where it very easily shows center view) but I feel something is stil off as my focus never gets perfect. And one of the times I tried to look at planets before they went behind the sun they where smeary and I couldnt focus enough to see more than the glare of Jupiters moons. They didnt unfocus into circular dots as to speak. They had weird shapes.

I thought you are supposed to inspect the defocused airy pattern at high magnification?

This is only for the primary? What about the secondary? Thanks

Nice video but my question is what is with the 1. Mirror??? You only used the 2. The main mirror?? Is this enough?

Dumb question here but do refractors need to be collimated? I've just gotten my first 80mm refractor scope and it has this sort of ball of light that comes downwards from any star or planet I look at

Is this method better than using a collimation cap?

Sooo capella is always below horizon where i live can i use another star?

So you don't ever need to get a laser or cheshire if you can sue this technique?

And what happens with the secondary mirror? 😳

Hello, I wanted to ask if I could look at stars without that spider appearing?

👍

I m not an expert but kindly confirm how much defocusing is required? I see you defocusing quiet a lot and instead of diffrection rings, the mechanical structure is getting visible 😊???

But what is with your secondary mirror ?

whats not to like. :) thnks

This a very fine collimation tutorial! But.... I do think that you are not quite right about the collimation-/"locking" screws, as you call them. The tilt of the primary mirror is adjusted with three pairs of collimation screws. The collimation screws can normally be turned with a Phillips head screwdriver and a 2.5mm hex key. Each pair of collimation screws work together to adjust the tilt of the primary mirror. The allen-head screw pushes the mirror forward while the Phillips head screw pulls the mirror cell back. One must be loosened and the other tightened by the same amount in order to adjust the tilt. This important to have precise adjustments on themain mirror.

That was easy😅 i printed a pattern, but then i discovered my tube is not even the right distance and not straight so when i assembled it bak I hadca nasty surprise hahaha

What role did Capella play in this tutorial...? Couldn't you have done all this without looking for a bright star in the beginning?

Do i need to collimate my telecope of it is a budget one? Like opticon 60F700.pls tell me

Can’t get rid of black dot in middle of view finder..😡

Alas! star testing like this will be a pain with a skywatcher dobsonian telescope :(

Skywatcher normally uses an Offset. You adjust your secondary mirror in the middle but this is wrong ...

What f have this telescope? Thank you

2:05 you sure thats a hand?😂

How often you should collimate your telescope?

I realy dont Like this newtonian stuff. For me colinating my netwons always feels soooooo subjectiv 🙄🙄 at least when you usw your eyes and not a Cam with circle-overlay

Hi the video is good but it's wrong and you are teaching people a wrong method of doing a star test. In the video where you are adjusting the knobs - you star is way way out of focus. For a proper star test you need to just be slightly out of focus so that you can see the diffraction rings and a small dot right in the middle

Thank you!