Think i might have messed up !!!

[Daveyboy]

hi all , being a complete newbie , I have read and watched videos on colomating a reflector . seeing as I own a reflector myself I bought a laser colomating tool a few weeks ago . my scope has given me some great views in wich I really cant fault to be honest but I have read so many posts saying you need to colomate every time you use your scope . so I used the tool today and the spot was a mile out ,, withought reading the instructions (cus im a bloke) I adjusted the primary mirror screws on the rear of the scope and got the dot centered . then (being a bloke) I read the instruction leaflet . ...  ... it doesn't mention touching the primary mirror   it just tells you to adjust the secondary (whoops). now as I look into the scope without an eyepiece in th center ring on the primary is way off center on the secondary . is this right or is it a case of getting someone who knows to sort it out for me ??? at this moment in time im feeling like a right div to be honest lol . any advise is greatly apprieciated . cheers and beers Dave

[Stargazer 2013]

This is from a moderator on here,pdf format but its for a  Newtonian

Collimation of Newtonian Telescopes-1.pdf

[houston]

I use a collimation cap to get the secondary right first then use a laser with 2x barlow for the primary. Theres loads of threads on here to read! Pain to start with but you will get better each time.

Sent from my GT-I8160 using Tapatalk 2

[Beechiller]

i'm a newbie too but im nearly sure you have to adjust the primary mirror as well as the secondary. I wrote up a post earlier about it. I nearly blinded myself with laser looking down the scope with half a bottle of wine in me

[ronin]

First thing to check is is the collimator actually collimated (aligned).

The collimator needs to sit in a V-block and be rotated and if the beam makes a circle on a convenient wall then it needs to be adjusted so that the beam stays as a fixed spot.

Then you can use it to collimate a newtonian. Unless the actual tool is correct you will be un-collimating the scope.

[weetooner]

This is the instructions I used when collimating for the 1st time-

http://www.astro-baby.com/collimation/astro%20babys%20collimation%20guide.htm

Good luck.

[John]

Assuming your laser collimator is itself collimated, stage 1 is to center the secondary in the drawtube, stage 2 is to adjust the tilt of the secondary and stage 3 is to adjust the tilt of the primary mirror. You need to do them in that order.

[AlexB67]

I'd have a watch of this video before doig anything to make sure the collimator is okay.

It is not the first time I've read where observers have been collimating their scopes with them only to find out their laser collimator itself was out after while.

[mashedpotatomountain]

hi dave

i'm totally new to this too but don't worry it's no big deal, it's a lot more straightforward than it sounds at first - best to learn it yourself, and you can't really do any harm (assuming you're not a total liability and go at it with a hammer), everything can be corrected.

(i almost went for a laser collimator too, but got a cheshire in the end. i may be wrong, but you shouldn't use the laser to collimate the secondary anyway - only the primary, and then only once the secondary has been sorted)

a lot of newcomers get directed to astrobaby's far more in-depth description of the process - but i don't have the link to hand, and anyway describing it to you might help me get better at it too

so here's me having a go at explaining…

• firstly, always perform collimation when the OTA is positioned horizontally - if done vertically, you risk dropping something into the tube and damaging the primary.

• either buy, or make yourself, a collimating cap. this can be made by piercing a very small hole dead in the centre of a photo film canister - or if you have one, a spare dust cap that fits in your focuser when not in use. (some might not want to do this to their only dust cap but i figured it's no harm done)

this forces your eye to look down the centre of the focuser as you would through an eyepiece.

• next, ignoring any reflections you're seeing in the secondary when you look through the cap, you need to adjust the secondary until it appears as a perfect circle in your view, centred with equal distance around it to the edges of the focuser. this means it's at the correct 45º angle and will direct light straight to the eyepiece.

this is done firstly by adjusting the central screw on the secondary mount - i think turning anti-clockwise should send the mirror further toward the primary (or right, in your view), clockwise brings it back out towards the entrance of the OTA (left, in your view).

if you're getting distracted by the reflections you're seeing, you can mask them out by carefully putting a piece of card inside the tube, blocking out the primary. just be careful as always not to touch the secondary or let anything drop onto the primary.

• then once you have it centred in the view through the cap, use the 3 adjustment screws on the secondary mount to rotate the mirror until you see the primary perfectly reflected back at you. most people use the retaining clips that hold the primary as an indication - when you can see all the clips reflected equally around the edge of your view, you're there.

this bit can be a bit tedious until you get the feel of how to manipulate the screws to affect the angle. simply put, you slacken one off slightly, and then tighten the other 2 slightly in order to affect movement in the direction of the one you slackened - does that make sense? and in small amounts, perhaps just a quarter turn at a time.

• your secondary should now be aligned...now you can insert your laser into the focuser, and use it to adjust the angle of the primary until it is reflecting the laser dot perfectly back at the laser's target. this may differ slightly depending on what model you have, and i've never even used one myself but i'm sure the principle will be the same.

when you're happy that everything is aligned, tighten the smaller retaining screws (next to each primary adjustment screw), not overly tight but just firm.

• once that's done, you should be good to go.

if you find you're getting differing results from a cheshire against your laser, then it's likely your laser needs collimating too (others will have advice on this). i'm happy i went with a cheshire, but as you have a laser i'm sure you'll quickly get used to that method too.

anyway i've probably got it all wrong and taught you my bad habits, but i'm sure plenty of more knowledgable folk than me on here will have given you better advice by the time i've typed this...

in fact you'll probably have figured it out yourself by now.

all the best

rich

[itmo]

Collimation is easy, just do it 20 times, then read the instructions, then do it 20 times correctly, then you get it right every time. Then you get collimation OCD and start worrying about getting it REALLY on the spot. 

[Daveyboy]

lol itmo.. many thanks for the replys guys ,, I think ive cracked it .. im the kind of person who doesn't really take it all in off paper . im the type who if you show me then it sinks in . after watching a few videos on youtube I think its now sorted . took me an hour or so but I finally got that dot in the center lol . the only thing im worried about now is that the secondary mirror is too far forward . when looking through the eyepiece you can see the front edge of the secondary , is this normal or should I bring it back a touch ? cheers once again for the fantastic replys  Dave

[andyman]

I use a collimation cap to get the secondary right first then use a laser with 2x barlow for the primary. Theres loads of threads on here to read! Pain to start with but you will get better each time.

Sent from my GT-I8160 using Tapatalk 2

Thats the way i collimate ....cant fault that method....very accurate