Collimation

[Gomtuu]

Not sure how the Barlow will work on the primary if the seconds is out? Please tell me as can't get my head around it lolA barlowed laser just acts as a projector

A barlowed laser just acts as a projector beam - correct.

You get an image of the centre ring (or spot) on the primary mirror reflected back to the laser's target area. Centre the ring on the target and bingo, your primary is collimated.

[jetstream]

Not sure how the Barlow will work on the primary if the seconds is out? Please tell me as can't get my head around it lol

A laser is not the best option for secondary alignment. The sight tube portion of the Cheshire combo tool is much better or better yet a separate sight tube for sec adjustment. A plain combo tool without the Cheshire face etched with an xtra set of crosshair marks is a good tool. A Celestron would be pretty good I think, not as "busy" visually http://www.celestron.com/browse-shop/astronomy/visual-accessories/eyepieces/collimation-eyepiece-125-in

[nicoscy]

A laser is not the best option for secondary alignment. The sight tube portion of the Cheshire combo tool is much better or better yet a separate sight tube for sec adjustment. A plain combo tool without the Cheshire face etched with an xtra set of crosshair marks is a good tool. A Celestron would be pretty good I think, not as "busy" visually http://www.celestron.com/browse-shop/astronomy/visual-accessories/eyepieces/collimation-eyepiece-125-in

Depends on what tools you use. The Glatter laser in my case performs the same as a sight tube and it saves me a ton of time.

[nicoscy]

Just to highlight something: My Dob is f4. The Glatter laser and tublug  are so accurate that I have no need for either sight tube or cheshire during the collimation process despite the very fast focal ratio.

[Dave In Vermont]

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My main complaint about the Hotech is that it is either "on" or "off".  There is no way do dim it down for collimation at a very dark site.  I think the fairly new Orion laser can be dimmed.

Clear Skies

Hi John,

I have the newest Orion - LaserMate Deluxe II, and regrettably it has no dimmer-function. But don't let this dissuade you from buying one - should the need arise (to fill yet another of your infamous "drawers.")

Orion swears these are collimated at the factory and set to remain this way - or they will replace it straight away. Mine was exact and dead-on. While Howie Glatter lasers are absolutely top-drawer, but the Orion fits the bill completely without the pedigree of the Glatter offerings. What works - works. And that is the focus of these red-dot critters.

I went in to it last night, and was expecting there to be disagreement between the tried & true Cheshire and this laser, but there was none whatsoever. Therefore I stand by my recommendation of the Orion.

Clear Skies & Red Dots,

Dave

[buzzlightyear]

This is the response I got today from the seller which is good but not sure what to make of their collimation checks lol?

Dear James

Sorry for not replying earlier. I have just called my supplier about your problem and them told me to roll the laser unit on a flat surface to if the laser stay in the same place. I have checked one and have sent the laser unit to you today by first class service.

If you do not mind, please put the faulty one back into its packing when you get the new one. Then just mark is as 'return to sender' and them put it into any post box. I need to return it to my supplier for a replacement.

Sorry again

[Charic]

As long as the laser is horizontal?  I have the Next generation laser, and there are differing widths to the body along its length. There has to be, otherwise it would fall through the focuser, so  you have to make a 'jig' that holds the laser horizontal, just rolling it on a flat surface can incur an error in alignment.

Rotate the laser tool to see if the laser describes an  arc, if it does, you need to 'un-plug' the three adjusters (affecting warranty? maybe not, as the tool is designed to be adjusted, thats why their fitted)  to correct the  laser beam alignment, and jig test again.

At about 18 feet, my laser describes a dot on target, but in  the focuser  ( due to focuser slop,  the laser tool is just not a perfect  skin tight fit) I can still get the laser dot to 'wiggle'?  A slight touch to the end of the tool during rotation fixes my issue, but using the Laser with a Barlow is my final solution and is the quickest method without faffing with 0.00005mm positional errors? Just get the 'shadow' centred and job done.

[buzzlightyear]

Well new one should arrive today so I'll see if it's better. If not I'll try adjustment and see what happens.

[buzzlightyear]

New one arrived and tried it, setting the red dots into position.

Now after I finished I put the cheshire in and now I can only see 2 clips in my view.

I'm starting to regret even buying a blumming laser collimation tool now and think they are a waste of time.

[Jason D]

New one arrived and tried it, setting the red dots into position.

Now after I finished I put the cheshire in and now I can only see 2 clips in my view.

I'm starting to regret even buying a blumming laser collimation tool now and think they are a waste of time.

Don't be too hasty to blame the laser.  The problem with collimation is that there is lots of unintentional misinformation and misunderstanding out there.

Lasers are not designed to help you see all clips. Think about it logically. The laser hits a tiny area on the secondary mirror surface. The laser does not interact with the secondary edge. How will the laser help you align the secondary edge with the primary reflection edge!!!! You need a tool that interacts with the secondary edge to complete this alignment. A sight-tube is an excellent tool. If you insist in using a laser then you need to use one with holographic attachment.

Refer to the following post

http://www.cloudynights.com/topic/214339-useful-info-about-secondary-mirror-alignment/page-17?hl=%2Bwindow#entry5260727

Jason