SCT Telescope Collimation (With NO fancy tools)

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Being out of collimation is not fun. Trying to collimate an SCT telescope can cause serious mental anguish. So instead of reading the instructions, you should watch this video first so you know what you're doing. Disclaimer: I don't know what I'm doing.
Shout out to High Point Scientific who know what they're doing.
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Опубликовано:

28 сен 2024

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Комментарии : 255

@DylanODonnell Год назад

Thanks for watching! And thanks also to @MarkusSchierz and @jesuspineiro1622 for reminding me that if you want to dial collimation in perfectly, you should recenter the star as well after each adjustment. Lots of love for Bob's Knobs too which I understand .. it's a great product. I found they didn't hold collimation for as long as the factory screws in the past and local stockists didn't have the zinc plated options I need in this case. Also .. you should loosen opposite screws first and then tighten target screw. I do this a bit in the video but don’t say so explicitly. And yes.. do be careful waving your PP around the scope glass in the dark :)

@aperturedriven Год назад

I think Bob's Knobs seem to lose collimation more often or more easily because the amount of torque actually applied to a fastener when it feels like you've tightened it fairly well is going to be different depending on the tool and even the size of the tool used. For example; try using your fingers, a short handle screw driver, and a long handle screw driver to screw a sheetrock screw into the wall. The more torque a tool can applied raised the psi required to "feel" tight. For this reason using a small plier or 3D printed level that attaches to Bob's Knobs would increase the torque necessary to feel properly tightened down and thus would most likely hold collimation much more consistently. I replaced my philips screws with allen head screws to avoid accidental stripping or slipping of the screw driver with my remote C11 Edge. Cheers!!

@AmatureAstronomer 5 месяцев назад

Thanks for extra instruction. 🙂

@k-d-n Год назад

Instead of a star, I always use a powerful flashlight covered in tinfoil, with the smallest hole you can possible make with a needle. This way you don't need the mount, and you can collimate your telescope indoors.

@lwizzit Год назад

I’ve been wondering how I might do this. It’s been cloudy here for weeks so I don’t want to lose any time if it ever clears up again. Trying this tomorrow! Thanks!

@JK-gn9qi Год назад

and on what distance?

@k-d-n Год назад

@@JK-gn9qi I my case, it's about 9 meters.

@OnceShy_TwiceBitten 5 месяцев назад

@@k-d-n how do you calculate that?

@conchobar 4 месяца назад

9m? Congrats, you have a large home.

@robertlowenthal689 3 месяца назад

This video was a lifesaver for my C9.25 Edge HD. I replaced the stock screws with Bob’s Knobs and messed up the collimation to the point where I had no idea where the secondary was pointing (my fault, not Bob’s). I felt hopeless and had no idea how to fix it. After watching your video, I removed the secondary mirror and adjusted it using a screwdriver shaft as a feeler gauge. I got it close enough that I was able to collimate the telescope in about 5 minutes. I hadn’t realized that I only needed to move the screws by a fraction to adjust collimation. Thank you!!!

@MakeAMark Год назад

Hey Dylan -- one of the most useful videos out there for SCT users. Thanks for digging in on this. I know there are a lot more subtleties to collimation, as pointed out in some comments, but this video really is helpful.

@DylanODonnell Год назад

Thx Mate!

@steppen57 Год назад

I am so scared of collimating my C8. I checked the collimation just a couple of nights ago, and it looked fine. But I will likely come back to this video. You make it look so darn easy. Thank you for this very instructional video. Love the closing as usual.

@dovthiessen 8 месяцев назад

I spent a lot of time initially calibrating my scope, understanding how it all works. I took the corrector plate off, cleaned it carefully. Replaced the screws with Bob’s knobs. I’ve found that the collimation needs to be checked and calibrated regularly. Similar to having to fine tune a guitar from time to time. Initially I bought a laser but the method in this video is the way to go. Bobs knobs make it simple to do this. Also , you can get that little donut image calibrated well enough so you can see many perfect concentric circles. It makes stars into perfect pinpoints. Worth the effort. I should note, I don’t have a computer hooked up to the scope, so I just adjust by trial and error and looking in the eyepiece.

@MarkusSchierz Год назад

Great video. However i think you forgot to recenter the star after your adjustments. For my c8 that makes a difference.

@jesuspineiro1622 Год назад

It is right. To perform a correct collimation, the star must be kept centered in the field and recalibrate. In SC, off-axis stars may appear out of collimation, but on-center ones are perfect.

@dwbattag5847 Год назад

My man you have upped your game! Every detail is so well covered and annotated watching everything that’s happening live at your point of the conversation is so helpful like you I will forget this until I look back at this particular. Saved RU-vid video. Thank you so so much.

@billbean5912 4 месяца назад

Best collimation video I’ve ever seen. Thank you.

@Photomanguru Год назад

Thank you so much for taking the time to make this top quality instructional video, I stopped looking for answers after I saw this. Keep up the GREAT work!

@wooddogg8 Год назад

Thanks Dylan, all this time collimation has had me afraid to buy that SCT I've had my eye on. Didn't realize all I needed was my pp. I've got pp. in fact I've got multiple pps in a large range of sizes and shapes, even 90 degree pps for that tight work without much space. Thanks, I've been subscribed for years but came here through the link in the High point scientific write up about you. Good stuff mate!!!!

@DylanODonnell Год назад

Bro thanks so much ! That was very kind of them to post that write up!

@rtpman1953 Год назад

Great video, Dylan, and I never knew it could be so easy by just letting my p p do the work. Likewise, I'll be saving your video so I can tackle my 11 Celestron SCT should we ever get a clear sky, hopefully before I get too old.

@DylanODonnell Год назад

I trust your PP will do just fine.

@dagriz 3 месяца назад

best collimation vid that I have found, i think ill be able to see Uranus perfectly now even from up here in the northern hemisphere :P

@allenbaylus3378 11 месяцев назад

got stuck before - bobs knobs - on my Meade 8 inch SCT. The star kept on moving out of the view on my ASIAIR - I will try again - I only wish it wasn't winter temps outside now. It's always inspiring to see other people do this with success.

@tamsoncat2358 Год назад

Sweet I just got my edgeHD 11 off Celestron this really helped out with my CGX-l

@DylanODonnell Год назад

Oh great !

@drunk_astronomy Год назад

Thank you for the video Dylan. Your videos always cheer me up when I’m feeling down.

@kevinburke8608 Год назад

In your pinned comment you stated that Bob's knobs don't hold collimation as long. I noticed in your old videos with the C9.25 that the "knobs" were really loose and wobbly. I'm curious if your old knobs were slightly undersized. I use them on my C9.25 and the knobs aren't loose at all and were the same size screw that came with the scope. They seem to hold collimation pretty well. I'm shocked that Celestron used a regular zinc screw instead of all three being black oxide. Must have been late Friday for someone in the assembly portion of the factory just before a weekend! Think they should give you a RASA 36 as compensation for your troubles :)

@davidleejenkins Год назад

Great video! I recently discovered how to collimate my SCT with a Tri-Bahtinov mask. Wow! It made it so much easier and more accurate too!

@philiphood8194 Год назад

You inspired me to check my collimation. A celestron EdgeHD is not like my meade LX90! The principal is the same but for a start the manual tells you to adjust the WRONG screws.( meade did fix) . Your process worked great. Allen wrench not philips head.Thanks.😂😂

@DylanODonnell Год назад

Excellent :)

@clearskiesastro1028 Год назад

It was my understanding and experience that every adjustment would push the target star out of the center of the frame...and on my C9.25 (non HD) if the star was off center, the shape would change in terms of how bad it looked in regards to collimation. So I'd have to adjust the screws, recenter the star, and then decide if I keep going...rinse and repeat. The star centering on a 2350mm FL scope is a pain in the PP.

@ABCMO-bl5pi Год назад

Absolutely great video! And you’re a braver man than I am because I don’t think I would ever have the nerve as part of the process to remove the secondary mirror from my C6.

@DylanODonnell Год назад

Thanks !

@janitkumar5234 Год назад

Appreciate your hard work , I am here after the ch3 amazing clip , what a shot that was

@DylanODonnell Год назад

Oh hey! Thanks for watching mate! 🇮🇳

@Xanthus723 Год назад

Hey these are the lessons I learned over the winter. I noticed the secondary mirror was flopping. I got everything tightened back down but couldn't achieve collimation for shit. Took the secondary mirror out and it was not even close to flat.

@Michael.Chapman 3 месяца назад

Love your observatory and the fantastic 3 minute collimation-awesome :-) When screwing the secondary holder back onto the secondary mirror assembly, did you ensure the secrondary’s rotational orientation was in its original factory position? I understand that my vintage 1970s/ 80s Celestrons were set-up at the factory for optimal rotational matching between corrector, secondary and primary to obtain best possible wave performance.

@DylanODonnell 3 месяца назад

Thanks! There is a groove so there is only one orientation possible to get it back in :)

@DylanODonnell 3 месяца назад

Not sure about vintage though sorry!

@sakuntharanaweera2457 Год назад

Woooooooowwwwwwww... THANK YOU SOOOOOOO MUCH and I really love this..❤ great, clear instructions and demonstrations.. ❤👌🤘

@DylanODonnell Год назад

You’re welcome I hope it helps !

@wbehrens62 Год назад

I put spring tensioners on my secondary screws "to stop the flop".

@virgill8502 4 месяца назад

Great video! As far as collimating an SCT; couldn’t you measure the gap between the two halves of the secondary with a feeler gauge (gap gauge), and make sure the gap is the same all the way around? Then collimate on a defocused star to do any needed tweaking.

@DylanODonnell 4 месяца назад

In theory, yep! In fact just eyeballing it that way get's it basically close enough, then tweak the rest.

@10intexas Год назад

Is it possible to make a collimation "band" to put around the mirror and the cap as a fixed spacer to make it impossible to screw the mirror to the cap out of alignment.

@frankbraker Год назад

Don't know if you mentioned using a ball bearing in the video (because I have a Newtonian), but yeah. If you're inside and don't want to fiddle pointing at real stars, you can cover a flashlight with some foil, put a pinhole in it, and point that toward a tiny ball bearing and point the scope at the ball bearing to simulate a teeny tiny star for doing collimation indoors.

@DylanODonnell Год назад

That sounds like a lot of work :)

@yobb89 Год назад

my meade has the same thing, random screws used, diy washer from factory, they just slap these things together cheaply once they get the parts made and ready for assembly

@AG-vk9gq Год назад

As an extra Astrophography Tool has an excellent collimation aid.

@SD-xb4yv 7 месяцев назад

wow - next time I need this doing - I will send you the £130 - thank you so much

@matthewbaker7513 Год назад

I have never looked through a collimated SCT. Every SCT owner seems to think they don't need it, but the views are always terrible. Curious.

@cyberblitz Год назад

Did you need to have your mirror orientation the same as before you unscrewed it, having the screw holes aligned the same as before you removed the mirror? I'm not sure, but i believe when this mirror is fitted in the factory, it is carefully calibrated and orientated. This is why you have the notch, so when you place it back in, it is orientated exactly where the manufacturer had it, giving you maximum collimation to start with before you even touch the screws for fine tuning. But then again, i could be wrong on this

@thierrymartin8378 2 месяца назад

This is not really collimation but for one position of primary mirror . Collimation means the axis of the mirrors are indentical Here it is not the case. For a SCT every time you change the focal lenght yoy have to check the qualite of the stars .

@skyscope7795 9 месяцев назад

Hi This is Omar from Bangladesh. I've got a Meade Lx200 GPS 8" telescope. I need to collimate my telescope. How may I do without camera settings? I mean manually. Thanks in advance.

@JAG9100 Год назад

i might have to do this on my C8, ive noticed weird stars after the summer temperature change.

@jamestickle3070 Год назад

Dog, I love that cheesy expression on your face in the thumb mail mirror shot. Peak nerd. It’s a thing of beauty. You look like you’re about to tell us 5 out of 6 dentists prefer…

@Skyman82 6 месяцев назад

Love your videos! I have an edge hd and was wondering if it matters if you collimate with or without the .7x reducer.

@DylanODonnell 5 месяцев назад

Shouldn’t matter.. collimation affects the front, not the back. But in theory I guess you could eyeball it in better if you collimated without the reducer.

@Skyman82 5 месяцев назад

@@DylanODonnell I ended up collimating at the native focal without the reducer and with the tri-batinov mask and got the best collimation. I think it’s better than the factory collimation.

@duke227 Год назад

Question? After the center star is collimated, should expect all or most stars to also look collimated?

@DylanODonnell 11 месяцев назад

unless your scope has a super flat field, you'll always notice coma around the corners.

@ScottDavies Год назад

Brilliant video 👍

@douglasfleming1 Год назад

D: are you using an HD 11"? Or ( like me) are you using an older C11 SCT? And: are you using a fast star step up? Hyper star? If so: worth it? Thx

@DylanODonnell Год назад

C11" Edge HD (Fastar Enabled) .. I used to use hyperstar on a c9.25" .. it's great!

@avt_astro206 Год назад

Nice video! Any tips on actually cleaning a telescope Mirror?, How often would You do it for a Newtonian?, Like every 3 years. Or Should Not worry about it? Thanks For your great Work man! Keep it up! 👍🏻

@DylanODonnell Год назад

I've not come to that point yet. When I do I'm sure I'll film it :)

@terrance_huang Год назад

why not just replace them with SUS304 stainless steel screws?

@tmrdarkstar85 Год назад

Dylan I have always used an artificial star , then checked on Polaris , not sure what you southern guys would use. I also removed those stupid AF #1 Philips head screws out of my Secondary and replaced them with Hex head bolts of the same thread type , nothing like stripping a #1 Phillips head while collimating. Why the hell Celestron ever thought that was a good idea to use them is beyond me. Edit: I want to note , since replacing the screws with hex head, I have not had to collimate my C8 in years now, Granted it does spend most of its time in the pelican case because I cant find someone to make me the 5mm m42 threaded adapter with the bolt holes to attach it to my 268m and filter wheel. The M42/m48 ring adapter from ZWO doesnt work because the threads dont stop and the camera spins as the scope slews. Which we all know is a NO NO for many reasons.

@DylanODonnell Год назад

Great idea !

@scottrk4930 Год назад

Thank you . This was a simple , clear and useful Video . There's no wonder why we all Subscribe and Like . Cheers !/SRK

@AG-vk9gq Год назад

Great video but one question..did you turn the focus knob in or out to make the star out of focus?.Does it make a difference?

@DylanODonnell Год назад

It just reverses the effects of adjustment so either way works .. just remember the adjustment on the target screw and opposite direction for the others :)

@ronlundgren4391 Год назад

Thanks Dylan, I’ve had my C8 for over 30 years and collimation has always been a mystery to me. There’s no removing the secondary on my model so I don’t know that I can get to a good starting point as you did? And after so long of tweaking it I’m sure it needs that reset. Anyone have any advice?

@DylanODonnell Год назад

Not sure .. hopefully someone can chime in!

@pigeond Год назад

So who should I contact in Australia to get those secondary mirror screws? I actually want to get some new screws for my 2nd hand C6 too.

@DylanODonnell Год назад

Here's where I got my handful! www.boltandnut.com.au/m3-x-0-50p-coarse-black-zinc-pan-phillips-ph1-machine-screws

@georges3799 Год назад

I grew anxious watching you remove and handle the mirror. And i broke into sweat when you held a dish of wd40 above it.

@carltanner9065 Год назад

" And remember, everything is meaningless and we're all going to be recollimated"😝😝

@johnalexandermcbryde9788 Год назад

awesome! gonna get my pp out and check how i'm hanging. thanks dude.

@TheAngryAstronomer Год назад

It would be cool if NINA had some concentric rings you can move around the screen and resize to aid with this.

@DylanODonnell Год назад

True !

@Rob_1472 Год назад

I think Al’s collimation aid is still available. I used it on my 9.25 3 months ago. Yesterday I 3D printed a tri-bahtinov mask and it’s still in collimation…with bobs knobs 😉

@GrundleStiltSkin Год назад

sharpcap does

@DuongLeh-u3h Год назад

Wsup brother I'm a fan after seeing your interview. Is it genuine?

@SydneyDunk Год назад

“It’s something that I don’t want any oxide near at all” he says - as he waves a screwdriver covered in wd40-rust over the top of the secondary..😅

@DylanODonnell Год назад

I did say be careful 😆

@davidtotten3042 4 месяца назад

In my humble opinion, everyone should invest in Bob’s knobs. Keep that damn screwdriver away from your optics. Yes, I know they are pricey for what they are, but a lot cheaper than replacing a corrector plate.

@ryanmichaelhaley Год назад

This is great, now if only I could collimate my chess game 😂😢

@TheCosmicGuy0111 Год назад

Woah

@hcic9860 Месяц назад

These SCT's really make me miss my Newtonian 😢

@heavyjohnny Год назад

I google myself too. But I always end up felling full of guilt shame and remorse.

@Lasastard Год назад

Collimation of my fast Newtonian honestly drove me crazy. Completely switched to refractors now - just don't have the patience for SCTs and Newts :D

@Fatal_Inertia Год назад

I am definitely siding with elon over mark lizardman

@mikegdroid 9 месяцев назад

Sad to hear that the mind virus has infected too.

@Astronurd Год назад

Just use a laser and align the secondary mirror until the laser return is on the origin point of the laser source. I'm kinda lazy 🤔.

@DylanODonnell Год назад

Yeh but I used only my PP

@davidlynch9920 7 месяцев назад

God has a plan for your life, Dylan.

@DylanODonnell 7 месяцев назад

nope

@DylanODonnell 7 месяцев назад

no plan for yours either.

@timcorso6337 Год назад

"I'll just google myself" - don't do that in public mate you might get arrested 🤣

@Astro_Ape Год назад

Best steps to collimate an SCT: - sell it - buy an Apo

@FAstroHD Год назад

To the left

@DylanODonnell Год назад

No judgement here

@FAstroHD Год назад

@@DylanODonnell Thanks, I really appreciate the safe place here

@Steve_The_Ignorant_Astronomer Год назад

You are F* up !!! LOL You make me laugh.....

@DylanODonnell Год назад

Haha I don’t know what you’re taking about. This was a very serious informational video.

@Steve_The_Ignorant_Astronomer Год назад

@@DylanODonnell It was it was !!!

@Steve_The_Ignorant_Astronomer Год назад

Dylan , question ... I watched your video on solar processing but can't seem to get it where I want to. Was wondering if I sent you the stacked video (tiff) can you see what you can do with it.... I understand if you can't or don't want to but want to see if I am doing something wrong

@OhanSmit Год назад

jeeze, with only my pee pee. darn

@1966wasp Год назад

Feast or famine on this channel...

@DylanODonnell Год назад

Hah the channel banner is quite explicit about expectations ;)

@brodymk45 Год назад

rip mak users (me)

@Megavoltamper Год назад

5 minutes collimation, in a 16 minutes long video. 🤔🙃

@DylanODonnell Год назад

This kind of pedantry is why I love you guys :) But yes if you time the time I actually spent fiddling with my PP it's less than 5m :)

@myownspace9666 Год назад

He says 5 min collimation yet the video is 16 mins long.. get your story straight ;)

@DylanODonnell Год назад

I demand a recount

@paths1111 Год назад

Thanks for the video! I replaced the Philips head screws on my EdgeHD secondary holder with M3 hex head screws, as I find that the long arm of the hex wrench makes it much easier to reliably make small adjustments, rather than aiming a pointed screwdriver towards my corrector plate and trying to guess how much I turned it the round grip. Much less prone to slip as well. One additional note is that collimation on a defocused secondary shadow is still relatively rough collimation, and is more an indicator of mechanical centering of the secondary mirror relative to the primary optical axis. However, because the SCT secondary is spherical and therefore has no optical axis of its own, centering is actually neither required nor sufficient for exact collimation (centering is extremely important for Hyperstar however, as it has a very strong optical axis). To dial in exact collimation, it is still desirable to actually examine the Airy disk and rings of an exactly focused, centered star. This after all is what the image is composed of, but the problem is that seeing often makes this difficult. I've found that the best solution for me is to use Metaguide (free) - its live stacking and high frame rate make examination of the Airy disk and first ring feasible under most reasonable seeing conditions, and the coma detection feature is much more sensitive than I can detect by eye. Lucky imaging on planets is where you'll really see the difference, as the scope is then (hopefully) diffraction limited rather than seeing limited and typically much more highly sampled. I'd be interested to hear your thoughts on it if you decide to give it a try!

@DylanODonnell Год назад

What a great comment .. thanks for the thorough exegesis !

@meadmaker4525 Год назад

Great video, but I kinda feel like Celestron needs to maybe go back to the drawing board and design a better mounting plate for that secondary mirror. No reason they can't machine a plate that mounts the mirror at perfect "zero" once the screws are installed, without mirror flop or lopsided attachment. As it stands, it's EXTREMELY fiddly and more than a little delicate. Can't understand why they left it the way it is, but maybe there's something I don't know.

@photogazer Год назад

I cannot believe that you rubbed the secondary mirror surface with a dry microfiber cloth. You just introduced small scratches all over your secondary mirror. Good collimation video, but you never rub any front surface astronomical mirror with a dry cloth, even coated mirrors. Always use soft cotton balls with distilled water, with a drop of Dove liquid soap if needed to remove fingerprints. Yikes, dude. Your poor example will doom users to do likewise to their mirrors and cause them damage.

@Michael.Chapman 3 месяца назад

He’s also handling the secondary by its edge-I’d wear appropriate finger stalls or gloves. I’d recommend only attempting cleaning if a surface is heavily contaminated… first, direct air, with a large blower, over the secondary surface to remove free particles, followed by the most gentle drag (no pressure) of pure cotton balls, soaked in a solution of 60% isopropanol / 40% distilled H2O, from mirror (or corrector) centre to edge. Use a new cotton ball for every stroke. Also, rotational orientation of the secondary, the corrector and primary must always be preserved, along with lateral shims if present-otherwise optimal factory mating of the optical elements into a train can be destroyed.

@rosscayley8773 Год назад

Nice Dylan. Another really quick and easy way Ive found for 'roughing in' an SCT collimation thats way off (especially easy with Bobs knobs) is to view the symmetry of the secondary vs the primary (and vs the baffle tube) by looking directly down the optical axis from the objective side, in daylight. By adjusting the viewing distance you can vary the relative size of the secondary and its obstruction of the primary, so that any asymmetry becomes obvious as an uneven 'ring' of primary mirror showing around the secondary. Its really easy and intuitive to adjust until it looks even, and you can do it during the day. It works so well that, in my experience, the subsequent star test becomes more a confirmation of good collimation than an additional step.

@DylanODonnell Год назад

Excellent tip!

@ABCMO-bl5pi 4 месяца назад

This is such a basic question that I’m embarrassed to ask it. Nevertheless, I want to make sure I’m following the details of this method correctly. My understanding is that the primary mirror is considered the objective in an SCT. As such, this means one should be looking through the visual back end of the telescope, not the corrector plate at the front end. Is this correct?

@rosscayley8773 4 месяца назад

Both ways work- obviously the conventional star test is the most accurate way to achieve perfect collimation, but since 'collimation' is basically just achieving the alignment of all the optical elements, and you can clearly see the relative alignments of these from the corrector plate end, assessing and adjusting from the front end also works well to quickly identify and correct major misalignments....its also easier, and you can do it in daylight too.

@ABCMO-bl5pi 4 месяца назад

@@rosscayley8773 Thank you!

@StarlancerAstro Год назад

why not add some small springs between the cap and the mirror to keep pressure so there will not be flop, I am actually surprised there isn't I have not taking my secondary apart.

@landspide Год назад

Suggestion... Get a box of black nitrile gloves from Bunnings 🙂👍 They're dual purpose for late night moon walks, shamown...

@DylanODonnell Год назад

Heeee heeeee!

@aaronwmorris Год назад

Meade SCTs are a bit different. Celestron secondary mirrors pivot on the central axis bump as you showed, but Meade secondaries use springs for tension instead of the central axis. A Meade SCT can be returned to the flat collimation by finger tightening all 3 screws all the way in (per the manual).

@brandonrunyon Год назад

I fixed my collimation by buying an esprit. Also, happy to see your kid out and about.

@deep_space_dave Год назад

Ah I miss those days when I had an SCT as collimation was so easy. Now I'm a masochist with a RASA and it's dredded tilt 🙂 One piece of advice though, after getting your out of focus star, do a counter clockwise turn of the focuser to level out the mirror as it likes to flop around. Collimation will be more accurate that way. This was the most clear and complete video on SCT collimation, so well done Dylan! BTW Bob's Knobs are cool but I heard that the regular screws hold collimation better. Thanks for the video and clear skies!

@DylanODonnell Год назад

Oh man I agree with everything you’ve said here!

@tubedude54 Год назад

Screws are screws whether they are regular philips head or Bobs knobs... I think what you find is people are afraid they are over tightening with the knobs as opposed to regular screws so they end up with loose Bobs knobs.

@deep_space_dave Год назад

@@tubedude54 Personally I like the knobs better so I don't have a screwdriver near my corrector plate 🙂

@tubedude54 Год назад

@@deep_space_dave I agree... trying to use that little screwdriver in the dark is a nightmare! You have to constantly shine a light to make sure you find the screwhead and you end up losing your dark vision. With the knobs you just use your fingers and feel them!

@joedenisco6033 Год назад

Dylan, That was priceless. The thin side needs to be tightened to PUSH it away from edge. Very easy to remember! Thank You, and I really appreciate all the advice you give to the community. Joe D

@VoodooEagle 5 месяцев назад

But it depends on which side you defocus. If you defocus a star in one direction, you need to tighten. If you defocus the star in the opposite direction, you'll need to loosen.

@denniswilde2013 Год назад

One additional step I would do is to mark the edge of the secondary at the notch so when you’re assemble them the mirror will be in the same orientation to the primary when reinstalled.

@DylanODonnell Год назад

Interesting .. in theory it should matter thought right? If the mirror is perfectly symmetrical anyway?

@denniswilde2013 Год назад

@@DylanODonnell Celestron usually matches the corrector and the primary rotation to produce the best figure, so I would logically presume they would include the secondary to produce the best image possible from the set.

@erykmozejko3329 Год назад

80’s I worked at the UK Celestron dealership: Astro Systems At that time Celestrons were very symmetrical but did have a “tipex”/“white out” dot on the corrector and the corrector cell to get them aligned. Although very symmetrical there would be a prime orientation for best results. The C11 and C14 would be less symmetrical and more critical as to the positioning of the corrector plate and secondary. We started selling Meade and found there was slightly more astigmatism on the 8” OTA’s so you could get a bigger drop in image quality if the corrector wasn’t in the optimal position. The 10” OMG those were a pain to tune. We checked and tuned every imported scope (we made our own newt’s) Our collimation bench was a 12” parabolic mirror in a wood frame. At the focus was a 1/16” ball bearing mounted on a vane. Off axis a light which was focused on the ball bearing. We had 2 pence pieces with a bore hole to mimic a star or pairs of bore holes to mimic a close pair of stars to see the resolving power. Looking through a scope I could see the ball bearing fill the field of view and the whole room reflected with the main light on. Lights out and the artificial star viewed at a minimum of 500x magnification we would look at the Airy disc and diffraction rings to get collimation and fine tune the scope. Looking at the Airy disc is the ultimate way of collimating a scope and judging it’s performance. The main downside of our set up was it was all set up horizontally. We should have got round to tilting the whole apparatus at 45° so the scope would flex and slump (including the optics) in a position that more accurately represented its typical position in use

@erykmozejko3329 Год назад

I have to add this demo is excellent, including the key point of backing off/tightening the opposing screws so balancing the pressure on the cell. Next step would be to fully focus the star and for once Dylan you’ll have to get an eyepiece out, and the most uncomfortable one at around 4mm and look at the Airy Disk and diffraction rings formed by a starts image and see how concentric and clean the image is Bearing in mind you will also be limited by every tiny slight atmospheric distortion your local conditions will throw up. The collimation rig I mentioned we used. I could tell from the vibrations if that was road traffic. Train at the nearby station or someone walking past the shop. Even though we had our collimation bench in the most thermally stable location. I could still see the rippling and eddies of air moving round in the room

@astroindianx Год назад

Nice intro, but you have already 140 iq

@johnadastra1754 Год назад

While I've had my Meade LX200 secondary apart, I have never tried it with my C925 EdgeHD. Meade used to have an ultra-thin flat spring washer between mirror and secondary holder to take up any wiggle room. It's very surprising Celestron has no mechanism that stops the secondary from flopping about during adjustments.

@robshaw6844 Год назад

@johnadastra1754 I thought the same thing when I took my 5SE SCT apart a year ago (after I spent 30 minutes on hands and knees searching the floor for one, assuming I'd not seen it drop to the floor). It makes perfect sense to a non-expert that a small, lightly sprung spring would help immensely.

@ExoPhotography1 Год назад

You can do better by almost focusing a star, move it around where it looks best and center it, make a few itterations and you Will be blown away with how much better the collimation can get!

@AmatureAstronomer 8 месяцев назад

When you put your glasses on, you look smarter. Makes up for your accent. About to collimate my SCT for the first time. Scary.

@robertsipes7391 Год назад

First off, I think it is great that no matter what string of short clips you use in the intro to Star Stuff, that you include the one where you chuck the can toward the observatory dome. I must say, from the beginning days of your channel, that one has always been my favorite. I have said that the day Dylan O'Donnell leaves that clip out of his intro, that will be the day he has lost his soul for astrophotography. Oh well, I have a 2008 Celestron CPC1100 that needs collimation. Thanks for sharing and thanks for being Dylan. I hope your family is doing well also.

@poisonpen26 11 месяцев назад

My faststar slider is abit stuck and wont rotate to expose the collimation screws what should I do?

@RIDERZcouk 10 месяцев назад

Nice but you forgot to recentre the star after each adjustment

@bofblog Год назад

Great video...I read somewhere of AlsCollimationAid a free software collimation program..

@ezza2fly Год назад

Can you test for mirror flop once finished?

@astrojudebob Год назад

Thank you for the video. Perfect timing. I was going to collimate on the next clear night.

@DylanODonnell Год назад

I hope it helps .. good luck !

@psegre 4 месяца назад

Got it, thanks, I’m ready to collimate my edge 9.25, like right now, bye.

@helthuismartin 11 месяцев назад

You need a camera for collimation.Without camera collimation is a total nightmare..I had a Celstron C14 and it took me hours to get the collimation very good..

@roymedina638 Год назад

Great stuff but my PP stopping working years ago and I now play with my knobs for satisfaction. Thanks anyway Mate!

@DylanODonnell Год назад

Haha I don’t mind the knobs but they don’t hold collimation for as long as the normal screws and some don’t come with the zinc plating.

@roymedina638 Год назад

Well maybe I should start playing with my PP again and see if it still works. I’ll let you know Brother!

@videoaustralia Год назад

Surely they could design the mirror set up better so it sits perfectly flat before screwing the baseplate down. That's bullshit

@keithhanssen7413 Год назад

There’s always that one.bad.screw.

@amritseecharan848 Год назад

One of your best videos so far. Very very clear instructions. I image from Trinidad, and would like to share my images with you. Jupiter and Saturn are looking better every passing day

@DylanODonnell Год назад

Thanks so much !