Collimating a Newtonian Telescope (Celestron 130 SLT)
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- Опубліковано 30 чер 2024
- Collimation is super important for getting sharp even astrophotos. Make sure this is spot on before imaging. Its generally good practice to check the collimation whenever you introduce vibrations to your Optical Tube Assembly (OTA), during travel for example.
Some excellent Astrophotography youtubers to check out!:
/ forresttanaka
/ @astrobackyard
/ slymin1
/ @helenasastrophotography
Edit:
I just made a website with some more information about Astrophotography! It's got some great info covering the basics as well as a bit more detail about my process. Check out the Astrophotography section!
kmcaesium.com/ - Наука та технологія
Great video thanks! Got a Celestron 130dx it was way off, so much that the red dot scope couldn't be used at all. This video made it easy to collimate the scope with a laser and everything's good now! 👍
Thank you for this. I bought a 130eq and although it is entry level, I found it very difficult to collimate. Your video is a simple presentation but is quite different from the Celeston manual's recommendation. I have found posts dating back 8 years saying the 130eq cannot be collimated using traditional means, but I am using your video as a guide. Mars just passed prime opposition and it looked pretty poor in my scope. Thanks for the guide. Hopefully it will improve the view!
just picked this scope up for 250 tonight. its pretty dope. came with a cheshire collimator. im used to laser style though. i notice the focuser has some slop (common on these). i read up on cloudynights that there are set screws. ill try that. subd.
thank you for this! i was so confused !
good job
Thank you for the video. What screw driver you use for adjusting the secondary mirror. What type and size of screw driver please
2 mm allen/hex
@@kylemccaslin thanks
Hello, great simple video on how to use the laser collimator. I'm wondering about your mods. I guess you moved the primary mirror closer to the secondary so you could achieve prime focus with a camera. How much did you move it forward?
Yes, I moved the primary mirror up a bit to allow me to focus with a DSLR. I moved it forward around an inch if i remember correctly. I didn't notice any issues with the new position and the secondary mirror area so I assume that it still covers the whole beam, or atleast it works for my crop sensor camera. Here's the link to the video that I used to do the mod:
ua-cam.com/video/jDpSXPNCnS0/v-deo.html
Would one need collimate a 130SLT just due to moving it, carefully, from inside a home to out onto a backyard patio deck? Just how sensitive are these mirror's alignments?
From just carrying it inside to outside, I don't think you'd need to re- collimate. They aren't too sensitive, but if I put it in my car and drove to a site, I'd check it then each time.
If you have tried, which you didn't in this video, to adjust adjust the laser beam on to the spot at the back of the primary mirror because it was not aligned, then you'd find that it is a bugger to adjust, as the size of the adjustment points on the spider holding the secondary mirror onto the spider are very small indeed.
Yes, it is a bit odd to adjust the spider Allen screws since there isn't a real step by step but its definitely still very doable.
The good part about this adjustment though is that, assuming you tighten your screws well, you shouldn't need to adjust this very often. I have had my scope for about a year now and have only ever had to mess with the spider after I intentionally messed it up to see how hard it would be to fix.
@@kylemccaslin
Thanks. I think this is true about the secondary mirror. It looks held in place pretty tight. I am going to a hardware store to get a better range of small allen keys to help adust it. Maybe this will help. Adjusting the primary mirror is very easy however.
is collimating only for astrophotos or also for observation? i have the same telescope and i tried to see jupiter and it only showed a bright dot (couldnt even tell it was jupiter) i used the 25mm eyepiece... what are you suggesting me?
It does apply for observational but isn't as important for smaller targets. Would definitely recommend it though. I haven't personally done planetary on this scope but it sounds like you may want a barlow. Barlow lenses both increase the magnification and dim the image slightly. They are used in tandem/serial with the regular viewing lenses. Were you able to make out the moons?
@@kylemccaslin couldn't see the moon from the backyard but i'll try it!
@@thewalkingdeadrs4733 I actually meant the Galilean moons of Jupiter but sure
Does the cullimating laser piece come with the telescope? I just ordered one and haven't received it yet.
Not actually sure on that one. I got my scope used. Sorry I couldn't help with that.
No it does not, you need to buy a laser collimator separately (you can eyeball it too but the laser is more accurate).
Does this scope come with all of the stuff needed to do collimation or do you need to buy additional stuff?
I bought mine used so I can't say for sure but based on Celestron's website and on Amazon, it does not appear to come with a collimator. So it appears you'd have to buy that separately. I could be wrong though.
@@kylemccaslin I am kind of seeing the same thing in my research. Thanks!!
Not as intimidating as I though! Just one question, what collimator are you using?
Just your average laser collimator. The specific brand of the one i have is "Astromania"
@@kylemccaslin Awesome! Thank you 😊
Just a quick question. How exactly do we ensure central alignment in primary mirror. As I rotated the central screw in the front mirror and it is totally disrupted. I actually have a laser collimator too and I feel I have got it worse..any suggestions
Generally you don't touch the central screw in the secondary mirror's mounting. The central one is more foe securing the mirror than precisely positioning it. The other three are the only ones you should really be messing with.
If your central one is off now, I'd probably just suggest trying to get that back the the proper angular position by eyeing it then attempt to get the laser centered using the other 3 screws. If the rotation is off this could take a few tries but should be do-able.
@@kylemccaslin wow thanks for this quick response. In that case let's say I setup the central part . I am a bit confused when I check inside I shud be focusing on the red dot to be in the center ? I see that there r 3 red dots and it is wierdly confusing.. one of the attempts I got it but when I view in the front part , the laser red dot isn't visible at all. A bit annoying 🙄
@@kylemccaslin another query. When u say the laser to be centered..is it precisely only one laser red dot to be visible ??
@@vickyisust on each mirror yes. Do you have more than one dot??
@@vickyisust There should be only one red dot and you want it to be at the center of the big (primary) mirror. After you get to that point you want to move to the adjustment screws on your big mirror. By working these, you should be able to get it to move to be visible in the focuser (the view part at the front).
Is the telescope main mirror semi-permanent? Or do I have to replace it every few years? sorry I'm korean I'm not well English
The main mirror is permanent. The collimation if that mirror is not. I would check the collimation of the mirrors every time I transport the telescope with my car. If you are just moving a telescope outside then you don't need to re-collimate, but if the telescope experiences a lot of vibrations then I would atleast check the collimation.
Is there a way you can align it without the colmulator lens ?
Not that I am aware of. Some others may know a way though?
My secondary mirror is out of alignment and they didn't include the allen wrench. Great.
Also at first I was confused because the spider doesn't have normal screws like all the other collimation tutorials I've watched. So I started turning the thumb screws that hold the spider in because I thought maybe those were for adjusting it... until i took a screw out and realized my spider wasn't attached anymore. Am I screwed? I hope those screws that attach the spider to the optical tube don't need to be like, ultra precise or calibrated. I had to go to amazon and order some allen wrenches (I think the collimation adjustment on the secondary takes 2mm.) So yeah, having lots of fun with this thing already. 🙄
@@mercster Pretty sure the spider mounting screws don't need to be super precise, so you should be ok. Good luck!
I'm 3D printing some hand-tightening grips for the locking screws if you want some/the file, the only thing is they are for the M5 variant (BSH5X50FSS on BelMetric) They have the hex key inside for grip. Here is what they look like: i.imgur.com/6BDnkS6.png
Old comment, I know, but did you upload the STL anywhere?
I've asked many people who own this type of scope. Why is the secondary mirror movable and not fixed in place. Same for the Primary mirror. What is the point of Having these mirrors made to move? Collimation would be eliminated if these mirrors were fixed. No one has answered this question for months. Anyone???
Plus, if I even blow on the front three secondary mirror screws, scope gers out of collimation. Are those 3 screws generally that loose?
Begs my initial question, why are these mirrors movable?
I don't have a perfect answer for that but my best guess would be for two different reasons: Thermally and Financially.
Thermally, the scopes are vulnerable to expansion and contraction due to temperature fluctuations (I've used mine in anywhere from 90 F to 10 F conditions. Its effect should be minor enough that deflection due to thermals isn't noticeable by the majority of people, but it should still be there. Its also worth noting that the spider's legs are thin enough (as to not cause additional obstruction) that the secondary may be moved unintentionally by other physical disturbances especially due to the torques present in this type. The mirrors are quite heavy and the tubes are quite long compared to others. The ability to tune in that regard may be nice.
On the Financial part, its likely that manufacturers don't want the liability of permanently sticking it incorrectly the one time it is set. I've heard stories that the maksutovs can be a crapshoot because of this. Yet at the same time, the ability to tune this gives the end users a little bit of flexibility if they want to repair the spider or remove (to clean?) that secondary mirror.
But then to your point, alot of other models are either set by the manufacturer (like maksutovs or Refractors) or are tunable but rarely need it (like Schmidts). It probably just has to deal with how robustly the Secondary is mounted and that optical glass is more peculiar and more expensive.
Thats probably not the most satisfying answer, but that's my guess as to why.