Collimating Skywatcher Newtonian

[bluesboy]

Hi All

I have attempted a collimation of my Skywatcher 114 Newtonian with a Altair Laser tool. I think I got it right. Wont know till dark. I was wondering if I need adjust the 3 little Allan screws on the centre of the mirror? I think they adjust the tilt of the mirror.

I borrowed the Laser tool, should I purchase a Laser tool or a cheshire type?

Thanks in advance

[bingevader]

The 3 screws on the 2° mirror holder do indeed adjust the tilt of the 2° mirror and should be adjusted if necessary when collimating your 'scope.

You'd usually adjust these before adjusting the 1° mirror, but as long as your friend's laser tool is well adjusted and indicating that your 'scope is well collimated, I'd suggest leaving it 'til next time. 

Laser or cheshire, up to you really. I have no problems using a cheshire.

[wookie1965]

A laser is a great tool if the laser is collimated you cant go wrong with a Cheshire,  yes the three screws do adjust the tilt of your secondary mirror.

[bluesboy]

Thats great guys, thank you. I shall go for a laser tool and I should be able to keep the scope in tip top trim. Will try the scope when it is dark and maybe look at adjusting tilt when I do it next. Cheers

[ekim]

I too have tried collimating my second hand scope .also used a laser tool think ive done it right  but also will have to wait for dark  .....who new there was so much to learn I figured when I bought my scope id just be able to point it at the moon or star/planet n look , how wrong I was ....lol

[bluesboy]

It is bad enough with the cloud cover, at least you dont have to worry about collimation when you cant see through the thing

[ekim]

very true  just hope ive not ballsed it up

[bluesboy]

I think I will have to do it again. But did get some reasonable views of Saturn. Although the moon was very bright last night

[jamie56]

Hi bluesboy,

Had a similar situation with my scope, went for a laser collimation tool, when it came it was out of collimation also and after many frustrating hours trying to collimate it gave up. Have since got a quality laser one and is very good, have collimated scope in next to no time, the second one I purchased is a Badder planitarium, bit pricey but well worth the extra bucks, hope this helps. Happy gazing and clear skies.

Jamie

[bluesboy]

Not sure about the Laser one now. Used aCheshire type today, took all of 10 seconds to do. Bit torn now as to what type to get?

[Moonshane]

I think you have answered your own question.

[Cornelius Varley]

Is the telescope the 114/500 version or the 114/1000 short tube ? If it is the latter then a laser won't be of much use to you anyway. The 114/1000 has a built in corrector lens that makes collimating with a laser difficult or impossible.

[wookie1965]

As Moonshane has already said you have already answered your own question and even in the dark shine a red torch on the reflective surface and same again 2 mins.

[bluesboy]

Yes, I think you guys a right. I shall be ordering myself a Cheshire type. Thanks for all your help. As usual a real benefit to us beginners.

[m37]

I ordered this one http://www.firstlightoptics.com/other-collimation-tools/premium-cheshire-collimating-eyepiece.html and it is very well made. Feels really solid and is well machined.

Never collimated a scope before in my life and it was surprisingly easy. Primary was way out but my secondary was spot on out of the box.

[wookie1965]

I ordered this one http://www.firstlightoptics.com/other-collimation-tools/premium-cheshire-collimating-eyepiece.html and it is very well made. Feels really solid and is well machined.

Never collimated a scope before in my life and it was surprisingly easy. Primary was way out but my secondary was spot on out of the box.

Yes more than likely the secondary will be collimated out the box, just a quick check make sure then leave it alone you wont need do anything with it unless you drop your scope or bang it. The primary will just need a tweak from time to time and the Cheshire will certainly make that easy.

[Myopicus]

I found that the wire cross-hairs on my Cheshire (the red premium one) were slightly off of centre.  Checked with my vernier gauge, and yup, about 1.35mm out. A bit of careful nudging sorted it .

Still not entirely sure what they are for though.     But at least they're straight.

[Moonshane]

the cross hairs on the cheshire allow for alignment of the secondary tilt. centre the cross hairs on the reflected donut and your secondary is aligned (assuming it is round and centred in the drawtube first).