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#1 daveyfitz

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Posted 06 February 2013 - 01:48 PM

Ok: After reading posts, reviews, product descriptions, and collimation guides ad nauseum, here's my idea:

- Use the collimation cap included with my (future) XT12g (12" f4.9 newt) to rough position my secondary.

- Get the Hotech SCA laser collimator, use it to fine tune the secondary to point at the center mark of primary.

- Use the Hotech with a barlow to adjust the primary.

- Down the road, if I really feel the need to get that last micro-ounce of collimation, get a catseye xlk autocollimator.
My logic:
- May miss having a sight tube, but its not needed that often, and C-cap will do the job.
(and 2" combo tubes are pricey)

- Barlowed laser method quick, easy, accurate for the nightly primary tweek.

- Hotech seems like a "best buy" in rear view barlowed laser.
(if one already has a barlow).
Is this a decent approach?

I welcome feedback from anyone not already "sick to death" of talking about collimation.

#2 csrlice12

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Posted 06 February 2013 - 02:35 PM

while it cost more up front; it will probably outlast you, the Glatter/TuBlug is well worth the price. No worrying if the collimater is out of collimation, is the beam the right size/shape. For tweeking the Primary, just put the dot in the circle and you're done. It actually takes more time to put the tublug into the focuser, turn on the laser, turn off the laser and put it away then it does to tweek the primary. And a from scratch collimation will be much easier, when a glatter system says you're collimated, there's a 99.999% probability its dead on. Unlike other cheap lasers, Howie tests each of his lasers to ensure they keep collimation by beating them on a piece of hard plastic a few time and checking to see that the collimation is still there. You would almost have to try purposefully to put a glatter laser out of collimation.

Not saying other systems don't work, or can't give you excellent results; but do you really want to try and collimate you collimater at a dark site????, and in the dark the manual caps just don't make it.......

#3 dpwoos

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Posted 06 February 2013 - 03:00 PM

Get a Glatter, and then stop worrying about collimation.

#4 daveyfitz

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Posted 06 February 2013 - 04:08 PM

while it cost more up front; it will probably outlast you, the Glatter/TuBlug is well worth the price. ......



Get a Glatter, and then stop worrying about collimation.




Interesing.

The 2" Glatter + tublug (for rear view) is $265.

The Hotech 2" SCA (rear view included) is around $100.

The Hotech has their proprietary "no slop" fit for near perfect focuser aligning/centering.

Wouldn't the lack of such a feature on the Glatter negate any minute superiority of the laser?

Both of you seem to be of strong opinion that the higher price of the Glatter is justified.

However, if I'm to pay more than twice the price, I would be VERY interested in what
specifically about the Glatter is so superior to the Hotech.

#5 csrlice12

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Posted 06 February 2013 - 04:22 PM

The tublug and the glatter are both finely machined to fit into the focuser tube, there is no "slop". You might be thinking of the "Blug", which is for Truss Dobs; that did need wedges to hold it in place. The Hotech is another good laser, but for tweeking the primary you'll need a barlow, and targets and taping stuff to the inside of the OTA, etc..........with the glatter, you put in the Tublug, put in the laser and put the dot in the circle...done. Also, the Hotech, while a good laser, will occasionally need checked to ensure it is still collimated.

You can do the "manual" method with a Cheshire/collimation cap and get very good results. A lot just depends upon the ease you want to collimate with. The Glatter is very easy to use, the Cheshire isn't hard to use, but is harder to use then the glatter. With the Glatter, there is NO "adjust the mirror, stand up, look in the eyepiece, go back, adjust the mirror some more, etc....), like I said, for the tweeking the primary, put the dot in the circle and you're done. It actually takes me more time to pull the Tublug and laser from their bolt cases and put them away then it does to actually collimate the scope (actual tweeking the primary collimation takes literally seconds). With the Glatter, you'll spend more time viewing and less time worrying about collimation....

#6 daveyfitz

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Posted 06 February 2013 - 06:06 PM

The tublug and the glatter are both finely machined to fit into the focuser tube, there is no "slop". You might be thinking of the "Blug", which is for Truss Dobs; that did need wedges to hold it in place. The Hotech is another good laser, but for tweeking the primary you'll need a barlow, and targets and taping stuff to the inside of the OTA, etc..........with the glatter, you put in the Tublug, put in the laser and put the dot in the circle...done. Also, the Hotech, while a good laser, will occasionally need checked to ensure it is still collimated.

You can do the "manual" method with a Cheshire/collimation cap and get very good results. A lot just depends upon the ease you want to collimate with. The Glatter is very easy to use, the Cheshire isn't hard to use, but is harder to use then the glatter. With the Glatter, there is NO "adjust the mirror, stand up, look in the eyepiece, go back, adjust the mirror some more, etc....), like I said, for the tweeking the primary, put the dot in the circle and you're done. It actually takes me more time to pull the Tublug and laser from their bolt cases and put them away then it does to actually collimate the scope (actual tweeking the primary collimation takes literally seconds). With the Glatter, you'll spend more time viewing and less time worrying about collimation....


Thank you for your post. I am glad to hear about the joys of owning a Glatter. Sounds like a fine piece of equipment.

However, I think I disagree with some of what you said:

If something fits into the focuser, then there is, by definition, slop to SOME degree.
If it slides in easily, with no lubricants, that requires a fair amount of clearance (slop). That slop is then "taken up" by the focuser locking screw.
In whichever direction the screw pushes the eyepiece, there is displacement from center, and perhaps displacement from alignment.
The Hotech expands its circumference to fill the slop, remaining centered and aligned.

As for needing "targets and taping stuff", I believe the Hotech + barlow is used in an IDENTICAL manner as the Glatter + Tublug?
If I am not mistaken, EVERYTHING you said about the glatter being quick and easy would apply to the Hotech.

The one distinction you make between the two is that you imply the Hotech will require periodic collimation.

Do you know that from experience? I haven't seen that expressed elsewhere.

Again, thanks for your insight.

PS: From your listed eyepieces, I intuit that $165 might mean a little more to MY pocketbook than yours.

#7 GeneT

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Posted 06 February 2013 - 06:36 PM

while it cost more up front; it will probably outlast you, the Glatter/TuBlug is well worth the price.


+1

#8 Mike Wiles

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Posted 06 February 2013 - 07:38 PM

If something fits into the focuser, then there is, by definition, slop to SOME degree.
If it slides in easily, with no lubricants, that requires a fair amount of clearance (slop). That slop is then "taken up" by the focuser locking screw.
In whichever direction the screw pushes the eyepiece, there is displacement from center, and perhaps displacement from alignment.
The Hotech expands its circumference to fill the slop, remaining centered and aligned.


I'll say this about both pieces....the Glatter tublug and laser are machined to such tight tolerances that the tublug has an additional hole machined in the side to allow air to escape as the laser is put into it. There is no slop in the Glatter stuff. I don't personally own one...but I borrow one from my observing buddy every time we're out together. It's the top of the heap.

I use a Hotech SCA field flattener on my imaging rig. The flattener works well. I'm underwhelmed by the "self centering adapter" in its design. In certain positions with the telescope, I'll get some flexure and slightly out of round stars. Wanna guess what the culprit is? It's the self centering adapter. It's a great idea in theory. It doesn't translate quite so perfectly to reality.

It's your money to spend or save - but Howie Glatter's stuff is far superior to the Hotech.

#9 Starman1

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Posted 06 February 2013 - 08:48 PM

If something fits into the focuser, then there is, by definition, slop to SOME degree.
If it slides in easily, with no lubricants, that requires a fair amount of clearance (slop). That slop is then "taken up" by the focuser locking screw.
In whichever direction the screw pushes the eyepiece, there is displacement from center, and perhaps displacement from alignment.

Nope. The small thousandths of an inch don't matter to the centering of the optical axis, and besides, all your eyepieces are shoved sideways too. Self centering is a "marketing idea"--not a BAD idea, just not an essential one.

The Hotech expands its circumference to fill the slop, remaining centered and aligned.

True enough, IF no tilt is imparted to the laser as the SC device is tightened.

As for needing "targets and taping stuff", I believe the Hotech + barlow is used in an IDENTICAL manner as the Glatter + Tublug?
If I am not mistaken, EVERYTHING you said about the glatter being quick and easy would apply to the Hotech.

Not quite. The Tublug IS a barlow with a white screen to see the returned shadow on. With a barlow on the HoTech, you'll have to prepare the bottom of the barlow to see the shadow on a white surface. If you try to use the 45 degree screen in the HoTech, the return shadow will have passed through the barlow lens and it will be larger, dimmer, and harder to see.

The one distinction you make between the two is that you imply the Hotech will require periodic collimation.

Do you know that from experience? I haven't seen that expressed elsewhere.

Once collimated, unless dropped or bumped, most lasers will stay collimated once they ARE collimated.


PS: From your listed eyepieces, I intuit that $165 might mean a little more to MY pocketbook than yours.

Well, if you buy a straight 2" laser from Glatter with the barlow attachment, it's only $150 + $35 = $185 The Hotech 2" laser is $120 and has no barlow attachment. So the difference is $65, not $165.

#10 pdfermat

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Posted 07 February 2013 - 12:17 AM

I can't praise Howie's tuBlug/laser system enough. When I set up, I collimate my secondary and primary in literally under a minute.

If I had to choose between giving up one of the eyepieces in my sig to never use again, or have to give up Howie's tools forever, Howie wins hands down.

#11 FirstSight

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Posted 07 February 2013 - 08:30 AM

The tublug and the glatter are both finely machined to fit into the focuser tube, there is no "slop".


I'll also give Glatter's laser and TuBlug the highest recommendation, these are buy-once tools that will serve you well for a lifetime. The machining and fit are extremely precise (to the point that when I insert my 2" Glatter into my Moonlite focuser, it goes in easily yet doesn't quite free-fall if I release it to let it drop in, but makes a gentle, satisfying "whoosh!" sound as it smoothly rides the cushion of air underneath it that has to escape through the snug concentric crack of space between the focuser wall and the outer wall of the laser body. The TuBlug is similarly a precisely machined, yet very rugged tool.

Did I mention how EASY and precisely accurate Glatter's 2" laser and TuBlug are? Superb ergonomics. Spend a few $$ more and get the best that will last you a lifetime, and have no regrets.

#12 FirstSight

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Posted 07 February 2013 - 08:44 AM

If something fits into the focuser, then there is, by definition, slop to SOME degree.
If it slides in easily, with no lubricants, that requires a fair amount of clearance (slop).


While I can understand the plausibility of this argument, it simply isn't true in practice with the Glatter laser. Its machining and fit are precise enough in a 2" focuser that it likely won't simply dead-drop in the rest of the way if you start it in and then release it. Instead, the fit is tight enough that it gently rides the cushion of air underneath it which it has to displace, making a pleasing soft "whoosh!" sound as the air is forced through the snug fit betwen the laser and the focuser walls. In fact, when I first got my 2" Glatter laser and tried it for the first time in my focuser, I was so astonished by this pleasingly intriguing phonomena that pulled it out and re-inserted it a couple of times just for the novelty of the experience. The TuBlug won't quite whoosh (has the hole in the middle of the screen), but fits snugly enough you'll likely need to gently wiggle and push it down into the focuser rather than dead-drop it in there, but with gentle force it goes down smoothly.

Howie is not just a talented machinist, but a very creative inventor with a genius for finding simple solutions to hard mechanical problems requiring precision. He's also invented a no-slop 2"=>1.25" focuser adapter, for example, not that my Moonlite needed that particular item. He's invented an improved self-centering low-stress cable sling for large reflector mirrors that lots of people have incorporated into their premium dobs. If you have a chance to go to a star party sometime where Howie has his vendor's booth set up, he's a fun trip to talk with; he'll gladly take time to explain and demonstrate how his astro-equipment inventions work, even if you're just a curious rubber-necker and not a serious buyer.

#13 acochran

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Posted 07 February 2013 - 01:18 PM

My Hotech collimation was off. Sent it back to the factory. Came back better, but still off. Forget it.
Now use Howie Glatter.

#14 cloud_cover

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Posted 07 February 2013 - 01:50 PM

I have a Glatter laser courtesy of the guy who sold me the Dob. Never havign had any other laser before, I must say I can't understand the issue of slop nor collimation:
My laser is perfectly collimation and shows zero shift when turning around.
The laser dot also does not move when I try to jiggle it in the focuser, which it does not.
So all in all, I'd have to call it a fine piece of art :)
Having said that, I've decided to skimp on the Tublug by sacrificing a clear 1.25" dust cap: I cut a piece of paper the exact shape of my barlow lens, made a squarish center hole by the quarter fold method (commonly used to find a mirror center) then taped it to the inside of said dust cap. Since my barlow (the 2X GSO Barlow) is visible inside the focuser from the primary collimation screws, I can collimate in real time :)

#15 daveyfitz

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Posted 07 February 2013 - 01:53 PM

Thanks Don, I was hoping you might chime in, you seem very knowledgeable.

I'm going to use the term "RVBL" for rear view barlowed laser, i.e. turning screws at the primary while watching the 45° screen.

After your assessment, and all the passionate responses here, I will consider the Hotech sufficiently dismissed.

I offer homage to the mighty Glatter, and beg fogiveness.

One question:
You say:


Well, if you buy a straight 2" laser from Glatter with the barlow attachment, it's only $150 + $35 = $185 The Hotech 2" laser is $120 and has no barlow attachment. So the difference is $65, not $165.



I'm not sure what the Glatter "barlow attachment" is.
I'm guessing it WON'T give me RVBL collimating, which is what I'm looking for?

Though, (fingers crossed) does it?

If not, then I think my financial assessment stands:

If I want RVBL from Glatter, I need the tublug + laser (that's all, right, no barlow needed?), so $150 + $115 = $265.

The Hotech is available for $100 right now, thus the $165 difference.

Ok, maybe ONE more question:

If I go with the Glatter + Tublug, am I covered, even for secondary tweaking, or (Glatter help me) do I need more?

Thanks again, to all willing to tutor me here.

#16 psandelle

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Posted 07 February 2013 - 02:25 PM

Tblug/laser = no fear! It's simple, precise and really cool. Expensive is always a relative thing, but the difference in price, to me, is worth my time and anxiety (Did I do it right? Didn't I?). Also, Howie's good at answering any questions I might have (not that I've had any since getting the thing). Now if he'd just make one that was electronically self-collimating like those Gibson guitar tuning pegs that auto-tune....

Paul

#17 MikeRatcliff

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Posted 07 February 2013 - 03:41 PM

I got to try a Hotech during a demo at a club meeting. It seemed the Hotech no slop feature you use a twisting motion to expand some rubber O rings to hold the laser in the focuser, but it seemed like you really had to crank down on the twisting. I didn't care for it. This was 2 years ago and maybe things are different now.

Now I have the Glatter 1 1/4 laser and tublug, plus the Glatter 2" to 1 1/4 no slop adapter. I need the 1 1/4 laser for my small dob. This combo works really well.

#18 daveyfitz

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Posted 07 February 2013 - 03:47 PM

Don:

Your statement below made me think.


Once collimated, unless dropped or bumped, most lasers will stay collimated once they ARE collimated.


Since the Hotech is guaranteed to be collimated, and Hotech will re-collimate for free, and since I can access the collimation adjustment myself to V-block it if necessary, How about this idea:

- I buy the Hotech, and see if it's acceptable for my collimation needs.

- If I find, after using it, that the barlowed beam is just too weak and hard to see, then I pick up a Glatter tublug.

- The tublug will work with any laser, eliminating the washed out image from a double pass through the barlow, and providing that nice, big alignment screen.

- Thus, if I'm happy with the Hotech, great, but worst case scenario, I need the tublug and I'm still $50 to the good.
(Hotech is $50 less than Glatter 2" laser)

I have attached images sent to me by Hotech that show the barlowed Hotech with primary in and out of alignment.

It IS pretty dim with the 2x barlow, I'm hoping with the Antares 1.6x the reflection will brighten up.

Attached Files



#19 Starman1

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Posted 07 February 2013 - 03:49 PM

Thanks Don, I was hoping you might chime in, you seem very knowledgeable.

I'm going to use the term "RVBL" for rear view barlowed laser, i.e. turning screws at the primary while watching the 45° screen.

After your assessment, and all the passionate responses here, I will consider the Hotech sufficiently dismissed.

I offer homage to the mighty Glatter, and beg fogiveness.

One question:
You say:


Well, if you buy a straight 2" laser from Glatter with the barlow attachment, it's only $150 + $35 = $185 The Hotech 2" laser is $120 and has no barlow attachment. So the difference is $65, not $165.



I'm not sure what the Glatter "barlow attachment" is.
I'm guessing it WON'T give me RVBL collimating, which is what I'm looking for?

Though, (fingers crossed) does it?

If not, then I think my financial assessment stands:

If I want RVBL from Glatter, I need the tublug + laser (that's all, right, no barlow needed?), so $150 + $115 = $265.

The Hotech is available for $100 right now, thus the $165 difference.

Ok, maybe ONE more question:

If I go with the Glatter + Tublug, am I covered, even for secondary tweaking, or (Glatter help me) do I need more?

Thanks again, to all willing to tutor me here.

The barlow attachment I was referring to is one Howie makes that threads directly on the bottom of his laser. To see its white surface requires looking up into the focuser. If your focuser drawtube is short (as on many low profile focusers with 1.5" travels), you can easily see the white surface. Otherwise a small hand mirror looking up into the focuser is necessary. Some people have attached a small "dental" mirror to the spider so they can see the bottom of the laser directly.

If you truly want to be able to view the barlowed image from below while adjusting the primary collimation knobs, it will require the TuBlug.
The 2" TuBlug will have a much larger window to look through, and the image will not pass through the barlow before it presents on the "screen", so you will better be able to see it.

I am not a fan of adjusting the primary from below while looking up though. I don't really think this works well unless the scope is really short. Everyone I know ends up standing up to more closely examine the image on the screen because they cannot really focus well on the screen from down below. I've even run into people who keep a small close-focus monocular with them to look up at the screen with enough resolution to be able to carefully adjust the primary. So I think most people end up standing at least once or twice, even with a TuBlug, to get the shadow perfectly centered around the hole.

But I find centering a circular shadow around a circular opening easier than centering an oval shadow around an oval opening. So if I'm going to stand up anyway to more perfectly align the shadow, I prefer the barlow attachment on the bottom of the laser, where the shadow and opening are both round (because the screen is perpendicular to the optical axis, not at a 45 degree angle).

Now, I can see that it is possible to use a TuBlug differently: sit in a chair directly between the opening in the TuBlug and the bottom of the scope. That way, you can simply bend over to adjust the collimation knobs and sit up to look in the window at close quarters. In this way, you would be able to look in the window and see the shadow with precision AND be able to reach down and adjust the mirror. This would probably work fine as long as the focal length was <80".

But if you prefer to examine the primary center marker shadow from close up, you'll probably stand to look at it, in which case a Blug on the inside of the tube (attached to the bottom of the focuser) or Howie's simple barlow attachment would both work great.

Myself, on my shorter 12.5" f/5, I use a cheshire to adjust the primary and simply bend over to reach around the bottom to adjust a knob and then sit up to look through the cheshire again. I can go back and forth 5-6 times in less than a minute, and I'm VERY fussy.

In terms of cost, I haven't evaluated it, but a Glatter laser in 1.25", in a Glatter Parallizer adapter would be as accurate as the 2" but costs $10 more than the 2" laser. Either way, the $35 barlow attachment or the $65 Blug (2" focuser) or the 1.25" Tublug in the Parallizer adapter would work.

A good combination sight tube+cheshire for 2" (Astrosystems: $89) would do the job for you for less than a laser and barlow. So if it's a matter of cost, save the money and don't get a laser.
But if you want a laser, the Glatter at $150 is the best you can buy.
Farpoint is a good alternative at $120 (2"/1.25" version, 650nm with 0.8mm aperture stop, or a 1.25" version for $85) and also likely to arrive accurately collimated.
You can use a 1.25" TuBlug if you get the Glatter or Farpoint in a 1.25"/2" or 1.25"-only version. In both cases, you will need an accurate 1.25" to 2" adapter, though. If you have one of these, you could save money and get a 1.25" laser.

But having a 2" tool in the focuser reduces by one the number of possible misregistrations that can take place when you use your collimation tools. For 2" focusers, I recommend 2" tools. Remember, the HoTech is a 1.25" laser in a 2" adapter, IIRC.

There are many combinations that will work to give you rear viewing capabilities. In the field, though, you will need really acute vision to be able to accurately asses the centering of the shadow on the screen from down behind the mirror. And the lowering of contrast that happens if the shadow passes through the barlow on its way back to the screen will likely require that you stand up to look at the image from up close.

Me, I don't like lasers in general, but, I admit, they are easy to use in the dark. If you have to set up in the dark, a laser is very convenient. I prefer using passive tools in bright twilight or even daylight. High-end passive tools aren't any cheaper than the best lasers, though, so it doesn't save much money to get the best passive tools either. A Catseye TeleCat combination tool in 2" is $111.

If you look at what it does, that $111 Catseye is a great tool:
--it can help center the secondary under the focuser, something a laser can't do without a special holographic attachment
--it can align the secondary mirror to the focuser axis
--it can align the primary mirror to the same axis.
And it can do so without ever removing the tool from the focuser to add a barlow or TuBlug, and the registration issue of multiple tools doesn't exist (I'm exaggerating slightly--alignments with Glatter tools are usually dead on). The one issue is seeing the images in the dark. A small clip on light will do the trick, though (see the Catseye website). So, alas, though tilt adjustment of both mirrors requires no sight tube, proper placement of the secondary under the focuser does.

Can you make a sight tube for centering? Sure, using a 2" piece of plumbing pipe and a cap on the end of the pipe in which you've drilled a centered hole. Out of pocket cost: <$2 at any hardware store. So you don't need an expensive sight tube to center the secondary when you can make your own for so little. But the 2" Astrosystems and Catseye combination tools can collimate your scope very accurately, even in the dark (with a small light) as well as center the secondary. One tool, in the focuser, never removed, to do all 3 functions. I think that beats a laser, no matter how good.

But, then again, once you do have the secondary centered under the focuser it doesn't drift out. At which point, a laser and a barlow (whether Glatter or not) will do the job in the dark and even allow checking in the middle of the night.

You have alternatives, and several are <$100, the price of a fairly inexpensive eyepiece.

Hope that's not too confusing.

#20 daveyfitz

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Posted 07 February 2013 - 03:52 PM

I got to try a Hotech during a demo at a club meeting. It seemed the Hotech no slop feature you use a twisting motion to expand some rubber O rings to hold the laser in the focuser, but it seemed like you really had to crank down on the twisting. I didn't care for it. This was 2 years ago and maybe things are different now.

Now I have the Glatter 1 1/4 laser and tublug, plus the Glatter 2" to 1 1/4 no slop adapter. I need the 1 1/4 laser for my small dob. This combo works really well.


Again, for anyone who doesn't like the Hotech locking mechanism, just use the focuser locking screw.

Seems to me you get the best of both worlds, twist the Hotech ring if you want perfect centering, perfect parallelism, use the focuser locking screw if that's not needed.

#21 csrlice12

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Posted 07 February 2013 - 03:56 PM

I belive you can use the Hotech laser in the Tublug. The advantage to the Glatter laser is it has a built in 1mm aperture stop built in, but the Hotech should work fine in the Tublug. And the Hotech IS a good laser, The Tublug system is just so easy to use (YMMV). And the truth is, they'll all collimate your scope, and that's what truely counts; however you collimate it, its going to give you good views.

#22 thetortoise

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Posted 07 February 2013 - 03:59 PM

Counterpoint: I have the HoTech and think it works great. I think the Glatter is almost certainly better based on the machining that goes into it, but have to say for $100, the HoTech has it's place as being much better than the next step down of the regular Orion lasers, which I have used and are almost laughably terrible. I get repeatable collimation off the HoTech, and mine has remained well collimated itself, so I wonder if the problems being mentioned are perhaps overblown (especially if the comments are from someone who doesn't have one and has never used one). Funnily enough there is a HoTech on the classifieds for $85 shipped that might be worth your while to try out. As much abuse as this statement may garner me: If the question is purely bang for the buck, the HoTech edges out the Glatter at $100 for good versus $265 for best.

#23 daveyfitz

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Posted 07 February 2013 - 04:05 PM

I'll say this about both pieces....the Glatter tublug and laser are machined to such tight tolerances that the tublug has an additional hole machined in the side to allow air to escape as the laser is put into it. There is no slop in the Glatter stuff.



Respectfully, "such tight tolerances" does NOT = "no slop".

If it fits, there HAS TO BE CLEARANCE.

Now, perhaps that is minimal, BUT IT EXISTS.

Subsequent tightening of the locking screw, MOVES the inserted accessory.
It also possibly takes it out of parallel.

You can read Howie Glatter's take on this in his description of his Parallizer accessory.

Lateral movement during tightening I would think is insignificant.

However, being out of parallel, even minutely, I would think could have a bad effect on collimation.

I'm absolutely sure Glatter's products are machined to specifications that are industry standards in MINIMIZING this effect.

But my take on the Hotech concept is that they have found a way to ELIMINATE, as has Glatter, with his Parallizer.

#24 daveyfitz

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Posted 07 February 2013 - 04:34 PM

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You have alternatives, and several are <$100, the price of a fairly inexpensive eyepiece.

Hope that's not too confusing.



Wow.

Now THAT'S a post.

I can't thank you enough for taking the time to so comprehensively cover the collimation options.

I actually HAVE been looking at the Telecat XL, and the Astrosystems Combo tube.

The non-directional backlighing of the Astrosystems Lightpipe sounds interesting.

I will be presumptuous enough to ask you a couple of questions:

Is one of them more capable than the other?

Will they get the secondary and primary collimated as closely as the barlowed laser?

The non-directional backlighting ability of the Lightpipe - truly useful, or a gimmick?

#25 Starman1

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Posted 07 February 2013 - 04:40 PM

Counterpoint: I have the HoTech and think it works great. I think the Glatter is almost certainly better based on the machining that goes into it, but have to say for $100, the HoTech has it's place as being much better than the next step down of the regular Orion lasers, which I have used and are almost laughably terrible. I get repeatable collimation off the HoTech, and mine has remained well collimated itself, so I wonder if the problems being mentioned are perhaps overblown (especially if the comments are from someone who doesn't have one and has never used one). Funnily enough there is a HoTech on the classifieds for $85 shipped that might be worth your while to try out. As much abuse as this statement may garner me: If the question is purely bang for the buck, the HoTech edges out the Glatter at $100 for good versus $265 for best.

Only if you count the barlow at $0. Most barlows will be $50 or more, and that should be added to the HoTech price if comparing to the Glatter + TuBlug.






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