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gaseous
30-08-2017, 04:40 PM
All right, I've had it with these cheap ebay laser collimators. I've got one which was perfectly collimated right out of the box, but the beam is so dim you can only use it in full darkness. Another is brighter than the sun, but beams a rectangle rather than a dot and I'm having the dickens of a time trying to collimate it into anything smaller than a dinner plate diameter. My chances of going all Dr Frankenstein on them and somehow combining the best qualities of both are doomed to end in tears and industrial-strength obscenities, so...

If I'm willing to shell out some proper money on a laser collimator (instead of ongoing installments of $20), what's the best brand? I can see Howie Glatter and Hotech as a couple of options that seem a step up in quality. Any preference for use in a dob? Thanks all.

rrussell1962
01-09-2017, 09:52 AM
Hi Patrick, I've tried a few on my Obsession and settled on a 1.25 inch Glatter with the Glatter paralizer which I found to be a step up from any of the others I tried. The Farpoint one was not bad either. But that is at F4.5 with a paracorr where the collimation tolerances get fairly tight particularly on the primary. At F5 and slower probably not as critical. When I had my 12 inch F5 dob the Farpoint laser and Cheshire worked fine. I still find a Cheshire or autocollimator the best, and easiest, tools to use for collimating the primary.

Kunama
01-09-2017, 10:03 AM
I have the Glatter 2" 635nm and 2" tuBlug which together are excellent, reducing collimation time to seconds instead of minutes...

Tested it in a 'V' block and its collimation is perfect !

Since Howie passed away recently, Starlight Instruments have taken over the manufacturing and marketing on behalf of Howie's partner.

gaseous
01-09-2017, 10:09 AM
Thanks gents, yes I noticed the Glatter website isn't taking orders, so I appreciate the heads-up for the new distributor.

I notice the website says the 635nm is for use at dusk and the 650nm is for use at night time - would it really make any difference which one is chosen?

rrussell1962
01-09-2017, 11:05 AM
Hi Patrick, have PM'd you.

Steffen
01-09-2017, 08:53 PM
Another excellent one is the Baader Mk.III Laser Colli. It has a smaller dot than the Glatter (0.8mm) and comes well collimated. It also has a glass screen for the return beam, to be used for CAT secondary collimation.

gaseous
02-09-2017, 10:21 AM
Thanks Steffen, looks like a nice unit. A pity (for me at least) the return beam plate isn't at 45 so you can adjust the primary on a large dob and see the return beam position at the same time.

Steffen
03-09-2017, 03:46 PM
For that purpose I would suggest a TuBlug, which can be used with any laser. It contains a negative lens and fans out the beam – what you centre around the hole in the screen is not the return beam but the shadow of the mirror's centre marker. That's why this method is largely unaffected by mis-collimation or poor fit of the laser.

wavelandscott
03-09-2017, 10:14 PM
The Howie Glatter gear is top shelf and one of his lasers and the tuBlug are simple to use.

Another outstanding set of gear is made by Catseye...you can not go very wrong with either set of gear in my opinion.

gaseous
06-09-2017, 05:37 AM
Thanks again guys, looks like I've got some homework to do.