HOW TO COLLIMATE YOUR DOBSONIAN (or any Newtonian Reflector)

I will show you how to collimate your Dobsonian or any Newtonian Reflector Telescope using a collimation cap, a Cheshire, or a laser collimator.

[@n8nelson2003]

I just got my Orion xt6 plus and have not collimated mine yet as I have just assembled it. Thanks Tsula, this is the best explanation I've seen. Thank you, I am glad I stumbled upon your video!

[@tsulasbigadventures]

Thank you! Have fun with your new Orion xt6. I have made a few videos about great targets for a Dobsonian that cover each season you might like as well. The one for spring will be released this week but you might find this one useful: kzbin.info/www/bejne/ZoiphqKmm72erpI

[@n8nelson2003]

Oh that's awesome. I will watch that video (along with many others that interest me of yours). I have sub'd your channel. My knowledge is none as of now, from what I've quickly skimmed through your content is great. Keep putting out content :)

[@tsulasbigadventures]

@@n8nelson2003 Thank you so much and feel free to ask my any astronomy questions at all. I'm very happy to help.

[@jrags35]

thank you to take the time to make the drawings, big help in understanding what I need to look for.

[@elray4932]

Excellent presentation, very well explained. Wish I had seen this when I was just starting out. Your video cleared up a couple of areas that were still a little foggy. This type of info is invaluable to the hobby. 😊

[@tsulasbigadventures]

Thanks, Elray.

[@MrGp3po]

I have used the collimation cap to adjust my Orion 10xti and then a laser collimator to discover the laser is off! The solution is to adjust the laser collimator with the three screws on its sides. You place the collimator in a V shaped jig like two small boards fastened together to form a 90 degree groove or cradle. Place a piece of paper on a wall say 20 feet away. Lay the laser in the V shaped cradle and turn on the laser to shine on the paper and mark the dot. Now, rotate the laser in the cradle about 90 degrees. If perfectly centered, the laser dot will not move on the piece of paper. Mark each dot and continue a full 360 degrees. Now mark the center of the dots; that is where the laser should hit. Adjust the screws and repeat the process until the laser dot doesn't move when rotated in the V cradle. This is how to correct the factory boo boo.

[@nish8435]

Thank you from India! Extremely well explained! Can’t wait to get my 8” Dob next month.

[@tsulasbigadventures]

Hello all the way to India. Thank you and congratulations on your new Dob.

[@tsulasbigadventures]

Thank you so much. You're going to love your 8" Dob.

[@JamesBond-sr7fw]

Great explanation! Thank you, just got my 8” Dobsonian reflector ☺️

[@tsulasbigadventures]

Thank you. And congratulations on your 8" Reflector!

[@gregerianne3880]

Glad you mentioned that the laser collimators can be 'off', Tsula! I actually had to collimate a couple of my laser collimators (yes, I went through multiple ones before I found asomewhat 'accurate' one). Not only can the laser collimator itself be out of collimation, but how it sits in the focus tube is important as you said, and it might change depending on how far out the focuser is racked. To get this so I could use a laser collimator, I collimated with a Cheshire, got everything set with that (not something I'd want to do at night!), then found the right way to 'seat' the laser collimator so it agreed with the Cheshire. Not a fun process by any means, but one you've put in the work, you can use your 'correct' laser collimator to quickly check and adjust your scope's collimation quickly. I'd love to see a star collimation video and (as someone suggested below) an SCT collimation. Not easy to do videos on, I imagine! Thanks again for all your hard work.

[@tsulasbigadventures]

Greg: Thanks for all the tips. You just reminded me that I forgot to say that the focuser should be racked all the way in when using the laser collimator. Also, I filmed this outside because my garage is dark and dirty but it is actually easier to see the laser in the garage than outside. I can make a follow up vide on collimating SCT and star collimation but yes, that one would be hard to show on a video.

[@kevincedeno8899]

Tsula, you are a treasure to the hobby. I've seen lots if collimation videos and none mentioned how to do a star collimation at night. Everyone just assumes the lasers are collimated.

[@tsulasbigadventures]

Thank you so much for your kind words. I appreciate it.

[@Astronurd]

I find that for the initial collimation of the secondary mirror placing a sheet of colored paper in the tube to block the primary mirror and a second white sheet flat directly opposite the focuser. This allows you to see that the secondary mirror is indeed centered in the focuser drawtube. You can also easily adjust the tilt until the secondary mirror is perfectly round and centered. This only needs to be done for the initial collimation whereafter only occasional tweaks are required. Clear skies.

[@tsulasbigadventures]

Those are good tips. Thank you.

[@jackieblank4249]

Great video Tsula. Collimator cap n star test #1works best. Lasers need collimating. Don't trust them ever. Clear sky's from the Bayou State.

[@tsulasbigadventures]

Thanks, Jackie. I prefer the good ole collimation cap.

[@26081829]

outstanding tutorial on collimation. thankyou.

[@tsulasbigadventures]

Thank you!

[@simonbodill]

Cheers Tsula I used the cap type and it worked a treat 👍🏼

[@tsulasbigadventures]

Great. Good job.

[@craiglowery4427]

I'd love to see how you COLLIMATE your SCT Tsula

[@tsulasbigadventures]

Coming soon!

[@glenncimera6421]

Thank you for the great video 😊

[@tsulasbigadventures]

You're welcome. Thanks for watching.

[@ericfrizzell2450]

Hi Tsula! I was thinking get rid of that little hex wrench and get a set of BOBS KNOBS. For your secondary mirror I did and I love them! Life is so much easier! Clear skys forever!!!

[@tsulasbigadventures]

I will have to look into that. Thanks for the suggestion.

[@hamishhunter6354]

Thank you so much for your video 🙏❤

[@tsulasbigadventures]

You're welcome and thanks for watching.

[@cigarnationwarriors]

I find that collimation cap works the best. Laser collimating devices are too iffy for this old backyard thumper. Thank you for another helpful video. Clear skies🔭

[@tsulasbigadventures]

Yes, the good old collimation cap seems the most reliable way to collimate.

[@ericfrizzell2450]

Great video Tsula ! I always wondered if that little dohnut circle is perfectly centered ? I'm checking that out next time I clean my mirror. Clear skys!!!

[@tsulasbigadventures]

Thanks, Eric.

[@jackieblank4249]

Usually they come from the factory alined and centered. Cut a piece of paper exactly the size of the mirror and fold it twice. Place it on the mirror and see where the point is. Should be close.

[@jackieblank4249]

Ps Eric. Don't rub to hard in the center r you risk loosing your center mark. Good luck and clear Skye's.

[@ericfrizzell2450]

@@jackieblank4249 I never rub on my mirrors

[@mazinalmoumen]

Probably it is safer to collimate while the telescope tube is in the horizontal position to avoid damaging the main mirror if a screw driver is accidentally dropped while collimating the secondary mirror 😊

[@tsulasbigadventures]

Good point! Thank you.

[@jackieblank4249]

Yes it's best to have it levell. Don't want to be dropping tools down in there and damageing your mirrors. I like to set mine up on a table or something where I can easily work around it. Just a lil tweek now nthen on the primary n good to go.

[@tsulasbigadventures]

@@jackieblank4249 A table works well if the telescope isn't too big.

[@ronm6585]

Thank you.

[@tsulasbigadventures]

You're welcome.

[@tuphdc8779]

Team Cheshire 👍

[@universeobserver378]

Are the tall skinny screws always the locking screws for the primary mirror, and the shorter round ones with the spring attached used for tilting? I'm unsure which is which on my skywatcher 8" traditional dobsonian. Thanks for the video.

[@tsulasbigadventures]

I'm pretty sure that the tall skinny screws are the locking screws on a Skywatcher as well. Skywatcher and Orion both made their telescopes for a while at the same factory in Shenzhen China.

[@pascalduquenne5947]

😎👍

[@tsulasbigadventures]

😀🙏

[@fazergazer]

First❤

[@tsulasbigadventures]

Thank you!

[@user-lg6ge8ts4e]

Some times the Lazer collocation needs collocation to

[@tsulasbigadventures]

That's what I have heard but I have no idea how to collimate a laser collimater.

[@TheBurak4141]

Hi, can we use the laser collimator eyepiece in a SCT?

[@tsulasbigadventures]

There is a laser collimator made for Schmidt-Cassegrain telescopes but it is made specifically for a SCT. I have never used one. Collimating a SCT is very simple and just involved turning two of the three screws at the front of the telescope. I made a video about collimating SCTs and explained more thoroughly.

[@freeman10000]

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