to collimate or not to collimate

[Stargazer_00]

soooo, Ive had my scope for a few months now and it's remain set up on its tripod the entire time.

I carry out to the garden for use and then bring it back in.

I am wondering if I need to collimate it. I read astro baby's guide and to be honest I'm not entirely clear if mine is OK or not..

I stuck a chesire colliamtor on it and the cross hairs on the collimator are no where near the spider ring cross. the spider ring cross goes perfectly through the centre of the secondary mirror reflection and the little circle on the primary mirror is exactly central on the spider vane cross hair.

the chesire colliator can be moved around quite easily inside the focuser even with the screws done up tight. seems like a bit of a flaw in the design that its so easy to move and due to the length of the tube just a small movement means the crosshairs swing quite alot in the image through the pin hole. I can, if i want, more the collimator tool to line up right over the spider vane cross hairs.

So i figure something is possibly up but the worst thing i could do is go bowling in and ruin everthing, considering it may actually be perfect!

Is there any real way of telling, from viewing in the EP, that it needs doing?

I saw the dark patches on Mars and its icecaps last night even with the moon glow... would i be able to see that if the collimation was screwy?

I'm dreading the first time I have to do this..

[Tribal-Wolf]

There are plenty of tutorials out there so read as much as you can. I have a cheshire and a laser collimator and I use the laser every time I get my scope out but only use the cheshire if I am making any 'adaptions' to the scope. I would say it may need collimating as a lot are way out from new.

[Stargazer_00]

can you advise on a good laser collimator? I saw a youtube guide on laser collimation and it seemed a real doddle compaed to doing it with a chesire (card and paper and all that sort of thing sent me chilly). The idea of simply turning a few screws to get a laser pin pointed doesnt scare me one bit.

I also hear that laser collimators themselves may also need collimation?....!

[Tribal-Wolf]

Well I bought one from ebay and have checked the collimation a few times and it's never been out. Mine is the same as this one

[Stargazer_00]

is this one good?

First Light Optics - Baader Laser Collimator

It mentions in FLOs description that the focuser must be good and I found that the chesire collimator moves around a little.. it is a crayford focuser.. i figured that would be ok?

[Tribal-Wolf]

Most Baader stuff is good but I haven't used it so can't comment. The HoTech laser is supposed to be very good. But I find mine works fine and the one on ebay is from Sky's The Limit who are a decent place to buy from.

[scoobymike]

I struggle with this too, as my visuals seem ok, but with photography I sometimes get stars that look like a pacman! When I collimate, these are faults that mostly disappear, so I would certainly think about it. Trouble is, as you've pointed out, that the collimator moves in the focus tube. I kinda go visually on the focus tube screws to get it as central as I can. Not perfect but better than nothing. If you go the laser route let us know how you get on..

[Tribal-Wolf]

As long as you fit the collimator into the tube the same way as you fit your EPs then it should not be a problem because they will collate anyway.

[stevetynant]

I have the Hotech and its easy to use - but you still need to make sure the secondary is lined up correctly before you can use it and thats where I have an area of uncertainty - the laser part is dead easy

[Mr Q]

If you want to check on its collimation, go to this site and compare your images with those shown. A simple star test will answer your doubts as to wether you need to collimate or not and this site shows you how -Thierry Legault - The collimation