Re: What is the best collimation tool to buy.
Of all the possible methods and procedures, Gordon describes my favorite when I really want a high level of precision. (E.g. great seeing conditions, new scope or mirror, long session and/or very difficult object observations planned)
In my experience the Orion laser or "simple laser method" as I like to call it, works fine. However, at least with my sample of the "Orion" device, it simply is not very accurate. My sample of the laser does not appear to be perfectly aligned to the holder and the pointer ascribes a circle on the primary, when rotating the laser assembly in the focuser.)
In my experience, the quality of the 1.25 to 2" adapter used with the cheaper 1.25" lasers can also introduce an additional margin of error.
But I will frequently use a cheap and simple laser/method anyway because; a) I don't have $300 USD burning a hole in my pocket, b) the cheap laser works pretty good and it's so easy, c) the result is typically good enough, and d) I still need to get one of those radiation cateye stickers for the scope/mirror I bought over 5 years ago and I have delayed getting the stickers because it needs recoating... still :-).
/Josh
On Fri., Mar. 4, 2022, 3:51 p.m. Gordon Pegue, < gpegue@...> wrote:
My 2 bits...
Lasers _can_ lie, if they're not properly and carefully aligned.
With that said, my procedure is as follows:
Assemble scope;
Check primary is seated in cell properly and no wonkiness in edge support;
Check spider end screws and secondary shroud screws (they can and do backoff unless you Locktite them - not sure if that's a great idea...);
Use sight tube to check gross secondary positioning (along optical axis of OTA under focuser and rotation);
Use standard 2" LaserMax laser to get secondary in ballpark (only secondary adjustment movements towards/away from focuser if laser dot is aligned with focuser axis on primary, then rotate secondary to get laser spot in center of primary center triangle - yes, I use the CatsEye system).
Once that's done (all the preceding usually takes about less than 2 minutes if I don't have to carefully tighten any screws), I use ONLY passive tools to fine adjust:
I iterate back and forth between CatsEye Cheshire for Primary and CatsEye Auto-collimator for Secondary until the multiple triangle reflections are stacked in the Auto-collimator.
The entire procedure takes just a few minutes.
Gordon
I have been using the collimating eyepiece that came with my scope and an Orion
laser collimator?in a 1.25 to 2 inch adapter?forever.? It works great.
Chris?
On Thu, Mar 3, 2022 at 10:47 PM Jeffrey D. Gortatowsky via <indanapt= [email protected]> wrote:
> Bottom line, is a $280 Howie Glasier 2" Laser a lot better that a $180 2" Barlowed laser or a $60 1.25" laser with a centering adapter?
No. Not even. A laser that when rotated in v-blocks that is close to center (ok, centered) will make your collimation look awesome. AFTER you use a sight tube.
I met Howie a few times at RTMC. I never bought his product because of how he treated his wife... you had to be there to believe it! IF you KNEW Howie, you know what I mean.
But that has NOTHING to do with his products. The laser is overpriced. IMO period. I *think* astrosystems?has a barlowed laser for about half that $280. Don't recall... I used?
it for a while.?
$280 bucks? Ya gotta be kidding.
JMO
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Re: What is the best collimation tool to buy.
My 2 bits...
Lasers _can_ lie, if they're not properly and carefully aligned.
With that said, my procedure is as follows:
Assemble scope;
Check primary is seated in cell properly and no wonkiness in edge support;
Check spider end screws and secondary shroud screws (they can and do backoff unless you Locktite them - not sure if that's a great idea...);
Use sight tube to check gross secondary positioning (along optical axis of OTA under focuser and rotation);
Use standard 2" LaserMax laser to get secondary in ballpark (only secondary adjustment movements towards/away from focuser if laser dot is aligned with focuser axis on primary, then rotate secondary to get laser spot in center of primary center triangle - yes, I use the CatsEye system).
Once that's done (all the preceding usually takes about less than 2 minutes if I don't have to carefully tighten any screws), I use ONLY passive tools to fine adjust:
I iterate back and forth between CatsEye Cheshire for Primary and CatsEye Auto-collimator for Secondary until the multiple triangle reflections are stacked in the Auto-collimator.
The entire procedure takes just a few minutes.
Gordon
On 03/03/2022 11:09 PM Christine Zeltner <czeltner356@...> wrote:
I have been using the collimating eyepiece that came with my scope and an Orion
laser collimator?in a 1.25 to 2 inch adapter?forever.? It works great.
Chris?
On Thu, Mar 3, 2022 at 10:47 PM Jeffrey D. Gortatowsky via <indanapt= [email protected]> wrote:
> Bottom line, is a $280 Howie Glasier 2" Laser a lot better that a $180 2" Barlowed laser or a $60 1.25" laser with a centering adapter?
No. Not even. A laser that when rotated in v-blocks that is close to center (ok, centered) will make your collimation look awesome. AFTER you use a sight tube.
I met Howie a few times at RTMC. I never bought his product because of how he treated his wife... you had to be there to believe it! IF you KNEW Howie, you know what I mean.
But that has NOTHING to do with his products. The laser is overpriced. IMO period. I *think* astrosystems?has a barlowed laser for about half that $280. Don't recall... I used?
it for a while.?
$280 bucks? Ya gotta be kidding.
JMO
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Re: What is the best collimation tool to buy.
Howie like Dave made his hobby into a business enterprise. What a symbiotic endeavor in a "perfect" world! The $280 price is certainly not Howie's last price, but profiteering from his name. Dave's Barlow-Laser at $185 is a fair price for today. I believe if my memory serves me correctly that I paid him $150 in 2004 when I picked up my scope at Okie-Tex. Through the years I have been content with that purchase. 
The sight tube, etc, are required on initial set up, but if you get everything tightened down well you are good to go. You can get very OCD about collimation, but any improvements in imagery will be negligible.
Unfortunately like Howie our resident collimation expert Nils Olof Carlin is no longer with us. I miss his undebatable mathematical authority.
Regards, and clear skies
#1138 20"
On Friday, March 4, 2022, 05:57:44 AM MST, Fr¨¦d¨¦ric Ruciak <frederic.ruciak@...> wrote:
Hi Bob, let us start by saying that you first need to check that the secondary is right at the centre of the optical tube and that the primary is centered too. As the primary might love a little when you drive I use cardboard etalons to do it on each side. Once done I start with a laser to turn the secondary and aim the primary center and then I use a combination of Cheshire and autocollimator to achieve both perfect? Cheshire and perfect autocollimation. You need to align your laser whatever you buy and I use 2 inches Cheshire and autocollimator. Hope this helps a bit Fr¨¦d¨¦ric?
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Re: What is the best collimation tool to buy.
Hi Bob, let us start by saying that you first need to check that the secondary is right at the centre of the optical tube and that the primary is centered too. As the primary might love a little when you drive I use cardboard etalons to do it on each side. Once done I start with a laser to turn the secondary and aim the primary center and then I use a combination of Cheshire and autocollimator to achieve both perfect? Cheshire and perfect autocollimation. You need to align your laser whatever you buy and I use 2 inches Cheshire and autocollimator. Hope this helps a bit Fr¨¦d¨¦ric?
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Re: What is the best collimation tool to buy.
I have been using the collimating eyepiece that came with my scope and an Orion laser collimator?in a 1.25 to 2 inch adapter?forever.? It works great.
Chris?
On Thu, Mar 3, 2022 at 10:47 PM Jeffrey D. Gortatowsky via <indanapt= [email protected]> wrote: > Bottom line, is a $280 Howie Glasier 2" Laser a lot better that a $180 2" Barlowed laser or a $60 1.25" laser with a centering adapter? No. Not even. A laser that when rotated in v-blocks that is close to center (ok, centered) will make your collimation look awesome. AFTER you use a sight tube. I met Howie a few times at RTMC. I never bought his product because of how he treated his wife... you had to be there to believe it! IF you KNEW Howie, you know what I mean.
But that has NOTHING to do with his products. The laser is overpriced. IMO period. I *think* astrosystems?has a barlowed laser for about half that $280. Don't recall... I used? it for a while.?
$280 bucks? Ya gotta be kidding. JMO
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Re: What is the best collimation tool to buy.
> Bottom line, is a $280 Howie Glasier 2" Laser a lot better that a $180 2" Barlowed laser or a $60 1.25" laser with a centering adapter? No. Not even. A laser that when rotated in v-blocks that is close to center (ok, centered) will make your collimation look awesome. AFTER you use a sight tube. I met Howie a few times at RTMC. I never bought his product because of how he treated his wife... you had to be there to believe it! IF you KNEW Howie, you know what I mean.
But that has NOTHING to do with his products. The laser is overpriced. IMO period. I *think* astrosystems?has a barlowed laser for about half that $280. Don't recall... I used? it for a while.?
$280 bucks? Ya gotta be kidding. JMO
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Re: What is the best collimation tool to buy.
Is it better, probably because Howie machined to very tight tolerances. Will the $180 do¡most certainly.
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On Mar 3, 2022, at 9:22 PM, bob414 <bob414@...> wrote:
Bottom line, is a $280 Howie Glasier 2" Laser a lot better that a $180 2" Barlowed laser
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Re: What is the best collimation tool to buy.
I agree that using site tube and a cheshire will do a good alignment, but you need some light.? Most cheshire systems incorporate a sight tube and aids in the alignment the secondary mirror.? This setting of the secondary mirror should be more stable compared to the alignment to the primary mirror with regard to scope transport, primary mirror shifting and truss tube slop, etc. on a Obsession 18" classic.
I was inquiring about the finish collimation.? Why use barlowed laser (never seen one)?? What does that do that a regular laser does not.? Is a 2" laser necessary, if a centering 1.25" adapter is used?? Even lasers should have their "collimation" checked.
Bottom line, is a $280 Howie Glasier 2" Laser a lot better that a $180 2" Barlowed laser or a $60 1.25" laser with a centering adapter?
Bob
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Re: What is the best collimation tool to buy.
Despite what some say.
No matter WHAT, you need to do a sight tube alignment at the very least.?
Otherwise all the lasers and barlows on the planet, will simply perfectly collimate your optics wrong (like pointing out the side! LOL).
JIMNSHO
And yes, after hitting up the sight tube on setup, and the cheshire, I finish it off with barlowed laser. Every night at a star party thereafter, just the laser for touch ups.
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Re: What is the best collimation tool to buy.
Third recommendation for Glatter.? I believe Starlight instruments makes them now.? shows all the options.? I use the 635 nm laser with my dob in twilight or dark.? It's a little brighter than the 650 nm.? They also make a brighter green laser which must be for setup in daylight.
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Re: What is the best collimation tool to buy.
I use the 2" on the Obsession site, and have been very happy with it. However in memory of Howie
Regards, and clear skies
#1138 20"
On Thursday, March 3, 2022, 11:20:11 AM MST, bob414 <bob414@...> wrote:
We were lucky enough to have a 18" Classic Obsession donated to our club.? It needed a little love to become useful.??
I used a Cheshire collimator to align the secondary and collimate the scope, to insure everything was in line.? We have been using a loaned 1.25 laser collimator and centering adapter to collimate after transport to observing sites.? We want to purchase a collimator for the scope.? The collimator on the Obsession Website is a 2" Barlow collimator.? How much better is that that what we are currently using?? Are there better options?
I know I am opening up a can or worms asking for the best collimator.
Bob
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Re: What is the best collimation tool to buy.
Second suggestion of the Glatter Collimator-
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On Mar 3, 2022, at 1:31 PM, Netscape via < P21932@...> wrote:
My favorite is the Howie Glatter collimator. When Howie passed it became unavailable but I think it is being remade (or was?)? On Mar 3, 2022, at 11:20 AM, bob414 <bob414@...> wrote:
?We were lucky enough to have a 18" Classic Obsession donated to our club.? It needed a little love to become useful.??
I used a Cheshire collimator to align the secondary and collimate the scope, to insure everything was in line.? We have been using a loaned 1.25 laser collimator and centering adapter to collimate after transport to observing sites.? We want to purchase a collimator for the scope.? The collimator on the Obsession Website is a 2" Barlow collimator.? How much better is that that what we are currently using?? Are there better options?
I know I am opening up a can or worms asking for the best collimator.
Bob
--
Mark Bungart
15" Obsession #643 / Swayze mirror
Grove City, Ohio
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Re: What is the best collimation tool to buy.
My favorite is the Howie Glatter collimator. When Howie passed it became unavailable but I think it is being remade (or was?)?
toggle quoted message
Show quoted text
On Mar 3, 2022, at 11:20 AM, bob414 <bob414@...> wrote:
?We were lucky enough to have a 18" Classic Obsession donated to our club.? It needed a little love to become useful.??
I used a Cheshire collimator to align the secondary and collimate the scope, to insure everything was in line.? We have been using a loaned 1.25 laser collimator and centering adapter to collimate after transport to observing sites.? We want to purchase a collimator for the scope.? The collimator on the Obsession Website is a 2" Barlow collimator.? How much better is that that what we are currently using?? Are there better options?
I know I am opening up a can or worms asking for the best collimator.
Bob
|
What is the best collimation tool to buy.
We were lucky enough to have a 18" Classic Obsession donated to our club.? It needed a little love to become useful.??
I used a Cheshire collimator to align the secondary and collimate the scope, to insure everything was in line.? We have been using a loaned 1.25 laser collimator and centering adapter to collimate after transport to observing sites.? We want to purchase a collimator for the scope.? The collimator on the Obsession Website is a 2" Barlow collimator.? How much better is that that what we are currently using?? Are there better options?
I know I am opening up a can or worms asking for the best collimator.
Bob
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Re: Calibrating the secondary dew heater
So, I came up with this idea.? For my 2.6" mirror it fits great and fills up to the back.? Now obviously once the mirror and dew heater are back in you will slice the back straight down to fit the new width.? But it should work very well.? You could also just stuff a little something in the middle?hole as well.? If yours is smaller, what is nice about this approach is that you can put a slit in it down the back and fold it in on itself as well to fit in the tube and therefore also reduce the middle hole diameter.? ?Another great use for a pool noodle !!!? Lol
I agree on the insulation behind the dew heater.? Mine had pillow batting behind it.? If the heater is the wrong size and too small you will also have problems.
Chris
On Sun, Nov 7, 2021 at 6:13 PM Mark Bungart < mbungart@...> wrote: Yep, I agree. Instead of gluing the heater, just cut some pink ( hard) styrofoam insulation to fit the gap between the back of the mirror and the secondary holder. The heater will be pressed against the back of the mirror and work just fine.
Im not aware of any calibration process for these. On Nov 7, 2021, at 6:46 PM, Roger Greenwood < roger@...> wrote:
Sounds like Astrosystems!
On Nov 7, 2021, at 6:18 PM, bob414 via <bob414@...> wrote:
?I wish I knew, it is powered by a 9VDC battery, has a red LED and a sensor that hangs out from the secondary.? I will try to look for a name brand when I disassemble again.
Bob
--
Mark Bungart
15" Obsession #643 / Swayze mirror
Grove City, Ohio
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Re: Calibrating the secondary dew heater
I agree on the insulation behind the dew heater.? Mine had pillow batting behind it.? If the heater is the wrong size and too small you will also have problems.
Chris
On Sun, Nov 7, 2021 at 6:13 PM Mark Bungart < mbungart@...> wrote: Yep, I agree. Instead of gluing the heater, just cut some pink ( hard) styrofoam insulation to fit the gap between the back of the mirror and the secondary holder. The heater will be pressed against the back of the mirror and work just fine.
Im not aware of any calibration process for these. On Nov 7, 2021, at 6:46 PM, Roger Greenwood < roger@...> wrote:
Sounds like Astrosystems!
On Nov 7, 2021, at 6:18 PM, bob414 via <bob414@...> wrote:
?I wish I knew, it is powered by a 9VDC battery, has a red LED and a sensor that hangs out from the secondary.? I will try to look for a name brand when I disassemble again.
Bob
--
Mark Bungart
15" Obsession #643 / Swayze mirror
Grove City, Ohio
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Re: Secondary Mirror Glue
I am pretty sure I used silicone glue on mine.? You use only? a very small amount.?
Anyone have suggestions for what to use to remount my secondary heater once it and my primary come back from re-coating ??
I have a circuit board looking dew heater that has 6 little elements that touch the secondary mirror and it appeared to have some kind of blue stretchy stuff directly between the element and the mirror ?? I thought it might be a Blue RTV Silicone ?? But someone said that that was not conductive to heat ??
Any ideas what I should make sure I use between the elements and the mirror to hold it in place?
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Re: Calibrating the secondary dew heater
Yep, I agree. Instead of gluing the heater, just cut some pink ( hard) styrofoam insulation to fit the gap between the back of the mirror and the secondary holder. The heater will be pressed against the back of the mirror and work just fine.
Im not aware of any calibration process for these.
toggle quoted message
Show quoted text
On Nov 7, 2021, at 6:46 PM, Roger Greenwood < roger@...> wrote:
Sounds like Astrosystems!
On Nov 7, 2021, at 6:18 PM, bob414 via <bob414@...> wrote:
?I wish I knew, it is powered by a 9VDC battery, has a red LED and a sensor that hangs out from the secondary.? I will try to look for a name brand when I disassemble again.
Bob
--
Mark Bungart
15" Obsession #643 / Swayze mirror
Grove City, Ohio
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Re: Calibrating the secondary dew heater
Sounds like Astrosystems!
toggle quoted message
Show quoted text
On Nov 7, 2021, at 6:18 PM, bob414 via groups.io <bob414@...> wrote:
?I wish I knew, it is powered by a 9VDC battery, has a red LED and a sensor that hangs out from the secondary.? I will try to look for a name brand when I disassemble again.
Bob
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Re: Calibrating the secondary dew heater
Sounds like an Astrosystems system. (no pun intended)
Here's a link. There you will find documentation and instructions.
On 11/07/2021 5:17 PM bob414 <bob414@...> wrote:
I wish I knew, it is powered by a 9VDC battery, has a red LED and a sensor that hangs out from the secondary.? I will try to look for a name brand when I disassemble again.
Bob
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Fr¨¦d¨¦ric Ruciak
Christine Zeltner
Netscape
Jesse Godsey
Dragan Nikin