Arrrgh Collimation tools

[Russty]

Ok right I'll try to keep this brief. I bought a 200p a few weeks back (which still has not had first light yet) . I used a MAK previously, the only collimating I had done was to help a neighbor collimate his eq130, he had bought a cheshire for the process and I couldn't help thinking it was a bit (lot) of a pain. So before I got the 200p I did nuff gooling to get some heads up on collimation of said scope, it saw lots of vids of people using lasers and thought wow that the tool for me, looks a doddle. So I bought an errm a next generation jobby with the 7 different brightness levels. So after setting up scope in garage and checking collimation with laser found it was out, so followed instructions and voila in 5 mins it was perfectly collimated or so I thought.

Now 200p has been sitting in garage for days now and in this time I have been reading again through AB's and astronomyshed bloke's (sorry astronomyshed bloke I don't know your name) guide to collimation and eek both say don't use lasers as they themselves need collimating and they can give false results from the "slop" when sited in the focus tube. so doubt was now setting in, was scope in garage not collimated at all. So after reding AB's guide again I decided to buy a collimation cap, for 3 quid I thought what the hey, also I remebered neighbors Cheshire and called round to see if he still had it, which he did (scope sold tho ) so I borrowed it. Now today, I decided to have a real go at AB's guide again printed it off and followed it to the letter (almost) with cap and cheshire. On completion i thought i would compare all 3 devices for the end result and not one of them agree with the other, if I change one tool for the other there are slight variations of Collimatedness (lol). So my first question is if a laser can suffer from "slop" then surely a cheshire can, which would also lead to false end results, the cap I bought seems to "click" into tube nice and securely and probably not "slop" so which tool is the most reliable as now I'm all confusled? My second question is, would a centering adapter help like the one astronomyshed bloke uses or am I being over critical and OCD ish?

I have Attached a photo of collimation If someone could have a quick peek at it and let me know if it looks right i would be grateful.

sorry it was a bit long winded.

Thanks.... Russ.....

[Stargazer_00]

Chances are its close, close enough anyway.

The slop to which you refer is introduced by screws holding the collimation tool in place, nothing else (unless your draw tube is not firmly mounted in the focuser, that could add some slop too i guess).

Self centering devices, like the hoTech lazer collimator I use, 100% get rid of this issue as they work by squeezing themselves into the exact centre of the space provided.

Another more readily available way to do this is with comnpression ring fittings. If you happen to have a generic 2" ED barlow that has the compression ring fittings. you could use that without the barlow element.

I first started with a cheshire colimator and I found it so sloppy I wondered how it could ever be accurate. You could move the long end a good half inch in any direction when you had your eye on it.

Since getting the HoTech I just screw it into place, turn it on and within 1 minute per mirror im 100% collimated.

your picture, by the way, looks fine. Certainly for visual use. Thats, even on a picture that size, within 10mm of perfect. That should be good enough for anyone who isnt taking photos.

[moffer]

No expert here, but for what it's worth....As things stand, I would go with the snug fitting colli cap.... that's the only tool I use and am perfectly happy with with the collimation on my son's new 200p. We were going to buy a cheshire, but after reading a few posts commenting on similar slop issues that both you and stargazing00 mention, decided against it and put the money saved toward a new eyepiece.

[Steep]

Did you center the laser before using it? if not there are guides on how to do that. That said my first collimation device was the same 7 level job and I followed the centering and collimation guides, got what I thought was pretty good collimation from it. After reading the many comments here about how a laser doesn't do the best job I bought a Cheshire and tried that method, the difference in sharpness when viewing the moon/planets is remarkable, Cheshire every time for me now.

[beatlejuice]

I would leave that alone, it looks pretty good to me

Eric