We hope that our telescope's optical elements are always perfectly aligned. Unfortunately, this near-perfect alignment is rarely the case, even with a new telescope. It is especially true with telescopes utilizing mirrors to direct light from an object to our eye. Optical alignment of these mirrors needs to be done frequently, especially if the telescope is moved or bumped a lot. This alignment process is known as collimation and using lasers to assist in the process is a relatively new development.
Howie Glatter is one of the most well-known and trusted names in astronomy lasers and collimation accessories. His uncompromising quality and dedication to excellence not only put his products above the rest - but in high demand as the finest available on today's market.
The solid-state laser diode in these devices emits an intense, low wattage beam through a small aperture, precisely along the axis of the collimator's cylindrical body. This beam provides a laser-precise reference line allowing alignment of the telescope's optical axes. A laser collimator's beam must be accurately aligned with the collimator's center axis, or the resultant alignment of the optics will be off-center and asymmetric, and the telescope will produce aberrated images.
Howie Glatter builds his collimators to be highly accurate and resistant to mechanical shock ensuring that internal laser alignment is maintained. The laser is first aligned within 15 arc seconds. Howie shock tests each collimator by hitting it against a block of plastic (to prevent marring), striking it several times on three axes. He then rechecks the laser alignment and if it has not changed, the collimator passes.
The collimators are supplied with a removable plastic aperture stop having a knife-edge, 1mm pin hole and a white screen front. The beam of all red diode lasers is blurry-edged and has an elliptical cross-section. The stop screws into the laser aperture and restricts the beam, producing a tiny circular dot (“impact”) surrounded by a series of concentric rings. The edge of the pinhole diffracts some of the laser light, forming the concentric rings which facilitate precise centering. With the stop attached to the collimator, the beam looks like a star diffraction pattern.
The collimator lasers are offered with either 635nm (this model) or 650nm wavelengths. Both have the same power output, but because the human eye has greater sensitivity to the shorter wavelength, the 635nm laser appears significantly brighter. The 635nm laser is more expensive, but it enables Barlowed or holographic collimation in higher levels of ambient light, whereas the 650nm laser is adequate only for darker conditions.
This 1.25" collimator is intended for use in 1.25" focusers. But the use of a 1.25" collimator is acceptable in a 2" holder if used with a "center accurate" adapter. The adapter can be checked for accuracy as follows:
- Insert the collimator and tighten the adapter
- Check the position of the projected laser beam
- Loosen the adapter, rotate, and retighten
- Observe if the laser spot has wandered from the original spot
- Total length = 3.38" (85.9mm)
- Length of 1.25" barrel = 1.61" (41.0mm)
- Maximum width = 1.32" (33.6mm)
- Weight = 5.7oz. (162g)
- Powered by a CR123A lithium cell (included), giving about 40 hours of service
Dave Bl New Member
- Skill Level
- Time with Product
Apr 19, 2017
- User Notes:
- Review by Dave B.
Best CollimatorPros: Cons: Comments:
I've had a few collimators over the years but since I started imaging with an 8" f3.9 I wasn't getting really great collimation without finishing with a star test. But with the Howie Glatter collimator and the barlow attachment I can get excellent collimation very easily. It's very nicely made, really sturdy. Should last a lifetime.
This review was provided courtesy of AgenaAstro.comApr 10, 2017
Howie Glatter 635 nm 2" laser collimatorPros: Cons: Comments:
This is a convenient and accurate laser collimator that fits a 2" compression fitting. The laser is well centered. Battery powered so no wires, turns on and off with a button press on the end. No fussing to use this collimator at home or in the outback.
Shipping by Agena Astro was very fast (2nd day), as always.
This review was provided courtesy of AgenaAstro.com
- Skill Level
- Time with Product
May 13, 2016
- User Notes:
- Review by Carl T of O'Fallon, MO.
Consistent,Accurate,Strong ConstructionCons: Comments:
I've been into amateur astronomy for over fifty years with my main interests lying in DIY-ATM. I've used many of the less expensive, and even the higher priced collimators and they don't hold a candle to Howie Glatter collimators. Each one is tested before it gets shipped out. I've verified the accuracy on a heavy V block and, at over 30 feet, the dot did not move as the collimator was rotated. This accuracy is necessary if you want spot on collimation of your Newtonian. Using this collimator on my Orion XT10g gives me great view of the planets and moon showing amazing detail when the seeing allows.
Glatter collimators are exquisitely machined and you know you have quality when you hold it. When you insert the collimator into the eyepiece tube, you get a good, square, consistent fit that you don't get with other collimators. The on/off switch is easy to operate and it holds a "real" battery that gives many hours of use.
There are numerous holographic attachments available that let you do more than collimate the optics. You can use the grid reticle to align and properly offset the secondary mirror.
If I lost my Howie Glatter collimator, I'd be buying another one the next day. It is well worth the price.
This review was provided courtesy of AgenaAstro.comApr 24, 2014
Most accurate and versatile collimatorPros:
Strong Construction,Easy to Use,AccurateCons:
I'm actually using the dual 2" / 1.25" model, owning a large newtonian, but willing to help smaller instruments owners (which I've actually done).
I recently bought a matching 1.25" TubLug, smaller and lighter than the huge 2" model, yet still precise enough. I'm using it with the Howie Glatter crosshair shaped holographic lens, allowing more precise secondary mirror centering than the standard small hole adapter, a square grid one to help fitting the secondary holder, and of course the barlow adapter, now replaced by the TubLug's embedded one.
This collimator is so tightly machined you can hear the air being chased as it slides inside the focuser, and it has no play at all, compared to cheap laser collimators. The integrated laser itself is also a sturdy professional one, using a large battery cell I never had to replace yet, despite intensive use. It's so well centered from factory in the aluminium body you can't see the spot moving at all when spinning the collimator inside the focuser. The new model includes a push button toggle switch on top of the battery cap, so you don't have to screw/unscrew it to turn the laser on or off, as on older models. All Howie Glatter collimators are a bit bulky and heavy because they're made of one chunk of solid machined aluminium, but it's a cheap price to pay for their extreme precision...
The laser spot is naturally a bit rectangular rather than perfectly round, as actually on most LED type lasers, hence the necessity for the small hole adapter. However, the crosshair holographic lens is much more precise here.
To collimate the primary mirror easily, you'll need a barlow lens. You could use your own with a white paper target and a centre hole, but the Howie Galatter screw-on barlow is just perfect. If you can rack your focuser down so the white surround can be seen from inside the scope tube, then collimating the primary will be a piece of cake. However, if you want to collimate from the back of a closed tube instrument without having to go back and forth, I strongly advise the TubLug, a barlowed tube with a side aperture and a 45 degrees target.
Otherwise, I'm especially happy with Agena fast and efficient shipping, quality packaging and competitive prices.
This review was provided courtesy of AgenaAstro.comNov 7, 2012
Accurate,Easy to Use,Strong ConstructionCons: Comments:
Well it's not cheap but it is outstanding. Fits perfectly in my gso and moonlight focusers. You can spin it around in the focuser and the red dot does not move on the primary. Very bright laser too so its easy to see in daylight. Very high quality construction. A cheap laser will do if you make sure its collimated but this one is perfect out of the box and zero frustrations. I use with the tublug.
This review was provided courtesy of AgenaAstro.comSort by
Manufacturer Howie Glatter