[mikeyjames (Mick)]

Originally Posted by billdan

Hi Mick,

I check mine (same scope as yours) every time I go to use it, and its always the secondary that needs adjusting but only about 1mm (from the inner edge of the white ring to the centre).

If yours is moving 2 -3 cm make sure the secondary screws are tight and also check that the spider vanes are tight as well.

Also rotate the laser in the focuser draw in case it is causing the wide discrepancy, this is probably the main cause of your problem. The lasers do need collimating by sitting them in a V block and pointing at a wall and minimise the circle it draws while rotating the laser.



Bill

Hi Bill,
My secondary is a bit loose and can be easily moved with minimum force. I was too scared tighten it up in case I broke something. So I can tighten the Philips head screw until the secondary can't be moved??

Thank you

Originally Posted by Robh

Hi Mick,

Adding to what Bill mentioned. Wind the focuser right in. Insert the laser and hold it flush against the focuser. Spin it around by hand slowly - does the beam stay centre or move around the primary in a circle? If it stays centre, tighten the fastening screw - does the beam move when you do this? Often, these lasers have quite a bit of play in the focuser.


Regards, Rob

Thanks Rob, it does seem it moves a bit when spun around so I guess my laser needs collimating as well.

I was actually reading an article earlier today where the author believes newbies should not use laser collimators because much of the time it actually results in de-collimating a scope that was fine in the first place.

Thank you

Originally Posted by RobF

For reasons above, a cheshire is often a better way of checking and setting alignment, unless you have a really good quality laser and already have your alignment close.

Sound like a plan. Thank you Rob.

Originally Posted by billdan

I got these instructions for laser collimation off CN but I can't remember his name, sorry.

Once you have the laser in a static position where it can only rotate, and not slide back and forth in any way then you can rotate it through 360 degrees . Number the laser collimation screws 1, 2 and 3 with a pencil (as this can write on the black tube) and then as you rotate mark the position of the spot on the wall when screw 1 is up, then 2 , then 3. Numbering the dots will help you work out which to adjust and which to slacken.

Next join the dots to form a triangle and then put a spot in the middle of this. Now adjust the screws to move the laser spot onto this. Once again rotate the laser to make the triangle, draw another centre spot and readjust again.

By doing this I managed to get a single spot when rotated within about 10 min’s and three "triangle" cycles.

Thanks Bill, I will definitely have a go at this.

Originally Posted by Cosmic

Hands down the cheshire collimator is the way to go. You would be surprised how out collimation can be with a laser, well the cheaper ones anyway. I collimate my newton 8 inch f5 maybe every second use, they stay fairly in tune if treated with love.

Thank you Daniel. I have a GSO collimator and not sure where it stands for quality. I think I will take the advice here and get a cheshire.


To everyone, I very much appreciate the help and advice
Cheers
Mick