Re: Don't do what I did :)
I agree, difficult to see if they are spots, tree sap, or what on the mirror. I clean mine once a year following Dave¡¯s instructions, using 2 gallons of distilled water. Add one drop of plain old Dawn detergent into one jug , shake and pour on mirror. Never ever rub anything on the mirror. If you need to, get some clean cotton balls and bunch them up wet and while the mirror is wet and soapy, drag the cotton across the mirror, never circular and apply no pressure. Rinse with distilled water. You can lay a cotton towel on the mirror to soak up any water but then just let it air dry.
If the spots are where the coating has flaked off, you need to recoat.
Mark Obsession 15, Swazye mirror
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Show quoted text
It is hard to tell from the pictures if it is water spots from dew or or general haze.? If a general haze it from the mirror coatingj slowly degrading.? They do that and you just clean your mirror?once a year.? I think the same thing works for water spots but not sure.
Do no rub on the mirror.
Chris
So, quick question.? I have the exact same look on my primary mirror.? Did you wash it a few times and always dry it with a micro-fiber cloth ?? Just wondering the best way to get it off and not scratch or damage the mirror.
Thank you.
--
Mark Bungart
15" Obsession #643 / Swayze mirror
Grove City, Ohio
|
Re: Don't do what I did :)
Yeah, I tried that but it did not remove whatever it is.
Pore distilled water at a 45¡ã angle if there's any droplets just soak them off gently by touching the tip of a paper towel to soak them up.
So, quick question.? I have the exact same look on my primary mirror.? Did you wash it a few times and always dry it with a micro-fiber cloth ?? Just wondering the best way to get it off and not scratch or damage the mirror.
Thank you.
|
Re: Don't do what I did :)
Pore distilled water at a 45¡ã angle if there's any droplets just soak them off gently by touching the tip of a paper towel to soak them up.
So, quick question.? I have the exact same look on my primary mirror.? Did you wash it a few times and always dry it with a micro-fiber cloth ?? Just wondering the best way to get it off and not scratch or damage the mirror.
Thank you.
|
Re: Don't do what I did :)
It is hard to tell from the pictures if it is water spots from dew or or general haze.? If a general haze it from the mirror coatingj slowly degrading.? They do that and you just clean your mirror?once a year.? I think the same thing works for water spots but not sure.
Do no rub on the mirror.
Chris
So, quick question.? I have the exact same look on my primary mirror.? Did you wash it a few times and always dry it with a micro-fiber cloth ?? Just wondering the best way to get it off and not scratch or damage the mirror.
Thank you.
|
Re: Don't do what I did :)
So, quick question.? I have the exact same look on my primary mirror.? Did you wash it a few times and always dry it with a micro-fiber cloth ?? Just wondering the best way to get it off and not scratch or damage the mirror.
Thank you.
|
Mirror recommendation and feedback please
Please find attached some pics of my primary out of my 15" F/4.5 Obsession.? Please let me know your thoughts.? I know it is not dust.
Thanks guys..
|
Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
We agree to disagree. Its garbage IMO. For 15K? The mechanics are garbage. For $15K? The VMB is weak. For 15K? The side to side causes issues.? For $15K? The alt cable needs to be perfect (and I have photos of how the company delivered it installed way off). Build quality was shite. For $15K apparently I you are *way* more tolerant of problems.? The UC22? Stay away unless you LIKE a $15K ATM project. And you like having no support.
JMO. I've said me piece. I'm done. I am repeating myself. For now...
----------------------------- Religion... together we can find the cure." - Richard Dawkins
On Monday, October 18, 2021, 11:49:49 AM PDT, ¹ó°ù¨¦»å¨¦°ù¾±³¦ Ruciak <frederic.ruciak@...> wrote:
Hi Mark,
to start with I own a classic 15 and a UC22 the real #1 UC22 both with AN/SC.
To make a long story short, the classic 15 was my first step to large aperture moving from a meade LX200 8'.
It was a revolution. But the fever was there and I decided to go beyond. I wanted something that would be the largest to feat in an Audi A6 avant. UC18 was too small from my 15 so I wrote Dave to warn me if there was something bigger ready to ship and I ordered the very first UC22 with something special: no foldable side bearings.
The scope moves for a one hour drive to "le Perche" south west of Paris where the sky is rural dark. I would never have been able to do so with a classic one.
I set it up alone in one hour including collimation. The UTA installation is the most sensible one cause you have to do it on top of your step ladder and you have to screw. Once you're done with two screws that's ok.
I can compare the pro and cons of the two concepts as seen from my experience.
Classic 15 it a lot smoother to move than the UC22, no discussion, the side bearings are narrower but I have AN/SC and it is not a real issue for me.
Regarding what I have read in this topic about the cable for the alt drive, as long as you take care of keeping the right tension on this cable when you unlock, the cable stays in place. The few times it got out I succeeded in restoring nominal installation in a few minutes alone. So not a big deal either.
True that there is a side move of the rocker on the UC22 that you don't have with the classic (thanks to the mirror box) but it generates no issue at all either optically or for pointing at least for me.
Regarding collimation, there is a real difference between UC18 6 truss tubes only and the UC22 8 truss tubes construction. The way the truss tubes are screwed on the UC22 is very good, you have not doubt that there are in the right position and tightly fixed. I personally have numbered them to be sure to screw the same tubes at the same place each time. The UC18 weak point is that the UTA is supported on three points only and the focuser is not supported closely with one on this three points. As a consequence you have more flexure of the single ring UTA. The UC22 has 4 support points for the UTA and the focuser sits very close on top of one support points. Frankly speeking I have had no more issue regarding the collimation that with the UC15 and I am a maniac. Moreover the mirror cell includes a clever improvement ie the two collimation screws bar is at the bottom when the scope is looking down. This choice combined with the natural flexion of the truss tube compensates the natural collimation shift that is observed with altitude in a dobsonian ()
Altogether, I am extremely pleased with the UC22. Yes it is not perfect, I made some improvements for the mirror box with a dismountable mirror box to better protect from light as well as adding a laminar air flow to cool the mirror above as well as light shield for the UTA but these are minor improvements compared to the initial design. Every year I participate to a star party in "le massif central" with several hundreds of astronomy amateurs, and I can compare the queue to have a look at the eyepiece in my scope with others of same aperture, guess what... either on Jupiter on the veil or M51 or M13, the views are just top, stars are crisp (focuser with built in paracorr).
I could never have such an aperture and load it in my car if not a UC22.
Hope this helps,
¹ó°ù¨¦»å¨¦°ù¾±³¦
|
Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
Hi Mark,
to start with I own a classic 15 and a UC22 the real #1 UC22 both with AN/SC.
To make a long story short, the classic 15 was my first step to large aperture moving from a meade LX200 8'.
It was a revolution. But the fever was there and I decided to go beyond. I wanted something that would be the largest to feat in an Audi A6 avant. UC18 was too small from my 15 so I wrote Dave to warn me if there was something bigger ready to ship and I ordered the very first UC22 with something special: no foldable side bearings.
The scope moves for a one hour drive to "le Perche" south west of Paris where the sky is rural dark. I would never have been able to do so with a classic one.
I set it up alone in one hour including collimation. The UTA installation is the most sensible one cause you have to do it on top of your step ladder and you have to screw. Once you're done with two screws that's ok.
I can compare the pro and cons of the two concepts as seen from my experience.
Classic 15 it a lot smoother to move than the UC22, no discussion, the side bearings are narrower but I have AN/SC and it is not a real issue for me.
Regarding what I have read in this topic about the cable for the alt drive, as long as you take care of keeping the right tension on this cable when you unlock, the cable stays in place. The few times it got out I succeeded in restoring nominal installation in a few minutes alone. So not a big deal either.
True that there is a side move of the rocker on the UC22 that you don't have with the classic (thanks to the mirror box) but it generates no issue at all either optically or for pointing at least for me.
Regarding collimation, there is a real difference between UC18 6 truss tubes only and the UC22 8 truss tubes construction. The way the truss tubes are screwed on the UC22 is very good, you have not doubt that there are in the right position and tightly fixed. I personally have numbered them to be sure to screw the same tubes at the same place each time. The UC18 weak point is that the UTA is supported on three points only and the focuser is not supported closely with one on this three points. As a consequence you have more flexure of the single ring UTA. The UC22 has 4 support points for the UTA and the focuser sits very close on top of one support points. Frankly speeking I have had no more issue regarding the collimation that with the UC15 and I am a maniac. Moreover the mirror cell includes a clever improvement ie the two collimation screws bar is at the bottom when the scope is looking down. This choice combined with the natural flexion of the truss tube compensates the natural collimation shift that is observed with altitude in a dobsonian ()
Altogether, I am extremely pleased with the UC22. Yes it is not perfect, I made some improvements for the mirror box with a dismountable mirror box to better protect from light as well as adding a laminar air flow to cool the mirror above as well as light shield for the UTA but these are minor improvements compared to the initial design. Every year I participate to a star party in "le massif central" with several hundreds of astronomy amateurs, and I can compare the queue to have a look at the eyepiece in my scope with others of same aperture, guess what... either on Jupiter on the veil or M51 or M13, the views are just top, stars are crisp (focuser with built in paracorr).
I could never have such an aperture and load it in my car if not a UC22.
Hope this helps,
¹ó°ù¨¦»å¨¦°ù¾±³¦
|
Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
The mechanical issues with the UC22, especially the so-called virtual rocker/mirroe box are unforgivable. It slides side to side pulling out the nailed in furniture glides. Yes, 15k and you get f'in furniture glides! The drive cable rides in about 1 inch (2.5cm) of either end of the grooved teflon on the Alt bearing. The rest of the bearing has a gap you can drive a truck through. And therefore it cable squirts out at the drop of hat. And the side to side motion of bearings on on the VMB/VRB makes it even worse as the cable tries to stay on the narrow bearing. And once that sucker slides off in the middle of a dark sky night, your night is OVER! Ask me how I know?! :( Then either you take the entire POS apart and remove the cable altogether and just use the Argo, or get 3 or more people to hold it, align it on the bearings, carefully PLOP 70 pound of garbage back on, hoping the cable is on, and someone has a drink (cause you are GONNA NEED ONE). $15k for a POS made by a dentist! Sorry if that is insulting. But the truth is that.?
Oh I *get* that he contributed many expensive scopes to the TRF in OZ, and that is great! Goodness knows I'd love to get to use one! Classics BTW, IIRC!!!! And everyone thinks he's sooo wonderful. But his company is selling garbage and no one seems to care. And he does nothing to make it right, like refunding the cost of the shite drive installation. So know he decides to ONLY sell the junk. Great.
I am sure if I had a 'Classic' I'd be a fan boy and not write this. My friends have them. And I love using and look through them. And I love LOOKING through the UC-22. The mirror and frankly collimation, have never been an issue. Its the mechanics that are crap. YMMV
?
---------------------------------------? Religion... together we can find the cure." - Richard Dawkins
On Sunday, October 17, 2021, 09:20:48 AM PDT, bobrose500 <bobrose500@...> wrote:
I have had a UC22 since 2010 and have no real issues with it. Any collimations issues I have had were self-inflicted. Example: I recently attended the OKieTex Star Party. 1st observable night, Set, up collimated, and observed until about 3:30or so. 2nd night checked collimation and it was off slightly. Found one truss pole that I had not fully tighten. Tweaked the collimation and had an awesome night. Rest of the nights checked collimation and found the donut centered. I use the Barlow laser method. This scope has Argo Navis and no ServoCat. My previous scope was a 20¡± f5 classic that I had added the ServoCat on then about a 12-year-old scope. It was a great scope with few issues. I found that I used the drives so very little, that I did not even consider getting them on the UC. I have a scope trailer that the 22UC lives in and have roughly calculated the milage of travels with that scope is over 20,000 miles. I show wear and tear about what would be expected. I have observed through 15 UC and 18UC¡¯s including UC#1. Never really saw any real issues with them. I have funny antidote about the 15UC that if you get around me to tell. Involves a person shaking it to see how collimation held up. I elected to go with the 22 and sell the 20 because of less weight and less ladder. I am getting older. I think a lot of collimation issues are because of bad seeing and not bad optical system. Large scopes are going to collect and amplify more of the bad seeing condition than a small scope. True for any large scope. I have been lucky enough to observe in sub-arc-second seeing conditions a few times. Not on this continent. Best detail view I have ever had of anything. Made Astro photos seem lame. It was through a 22UC. The build quality has not presented any issues with my scope. Especially seeing the number of miles, it has had bouncing around in the trailer. The overall design has also turned out to my liking and don¡¯t see any issues. I did make a few mods like different assembly bolts to speed up assembly in the dark.? That¡¯s my experiences with the UC line of telescopes. Bob Rose ¡°Have scope, Will Travel¡± ? ? ?
From: [email protected] < [email protected]> On Behalf Of Bob 1 via groups.io Sent: Sunday, October 17, 2021 7:55 AM To: [email protected]Subject: Re: [ObsessionUsers] Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer? ? I've logged hundreds of hours and seen thousands of objects with the UC18 since I purchased it from Dave Krieg in 2009 and have been very happy with it. ?I use it in "push to" mode with the Argo Navis and digital encoders, so have no experience with servo cat. ?Lately, I've been linking it to my iPad and Sky Safari, which also works well. ?The lighter but more portable UC design is clearly a trade off with the stability of the larger and heavier classic design. ?Living in the burbs under a canopy of 100 foot tall oaks and street lights, I need a portable scope, and the classic is just too much work (heavy and bulky) for me to comfortably transport 50 miles to a dark site when we have a clear moonless night. ?For the ease of transportation and assembly that the UC provides, I gladly live with the need to collimate the scope before every use, and with its tendency to lose collimation under certain observing conditions. ?I've done a lot of reading on collimation and have become pretty handy with lasers and other collimation tools. ? But even then, the collimation of my UC is rarely the limiting factor when doing visual observing. ?The atmospheric seeing and my imperfect eyes are usually where I hit the stops. ?And even though I have concentrated on faint fuzzies in the deep sky where the collimation of the UC is not critical, I also regularly check out the planets and, on occasion have been rewarded with HD quality views of Jupiter and Saturn. ?I've been observing for almost 50 years and can safely say that the views offered by the 18UC far surpass anything I've ever had with any other scope. ?This isn't to say there aren't better scopes out there, just that the 18UC is an awesome instrument when used within its limits. ?Over the years I've supplemented my UC18 with a 5" ED refractor on a GotTo mount for planetary observing, and a star tracker mount for my Canon digital camera, all of which complement each other very nicely I think. ?At least, I'm never bored. ?I hope to move out of the city and get a 25" classic when I retire. ?Now that would truly be AWESOME!
Bob Gardner
Falls Church, VA
?
|
Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
toggle quoted message
Show quoted text
What I did was to get longer thumb-bolts and take about ?¡± of thread off of them. Round then slightly on the end. Makes it easy for them find the holes and make it tough to cross thread. I stole the idea from distance auto racing.? F1 just has one big bolt that the wheel/nut goes over where NASCAR has a bunch. Bob ? From: [email protected] <[email protected]> On Behalf Of Christine Zeltner
Sent: Sunday, October 17, 2021 10:01 AM
To: [email protected]
Subject: Re: [ObsessionUsers] Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer? ? bobrose500 What assembly bolts did you change to? ? I have had a UC22 since 2010 and have no real issues with it. Any collimations issues I have had were self-inflicted. Example: I recently attended the OKieTex Star Party. 1st observable night, Set, up collimated, and observed until about 3:30or so. 2nd night checked collimation and it was off slightly. Found one truss pole that I had not fully tighten. Tweaked the collimation and had an awesome night. Rest of the nights checked collimation and found the donut centered. I use the Barlow laser method. This scope has Argo Navis and no ServoCat. My previous scope was a 20¡± f5 classic that I had added the ServoCat on then about a 12-year-old scope. It was a great scope with few issues. I found that I used the drives so very little, that I did not even consider getting them on the UC. I have a scope trailer that the 22UC lives in and have roughly calculated the milage of travels with that scope is over 20,000 miles. I show wear and tear about what would be expected. I have observed through 15 UC and 18UC¡¯s including UC#1. Never really saw any real issues with them. I have funny antidote about the 15UC that if you get around me to tell. Involves a person shaking it to see how collimation held up. I elected to go with the 22 and sell the 20 because of less weight and less ladder. I am getting older. I think a lot of collimation issues are because of bad seeing and not bad optical system. Large scopes are going to collect and amplify more of the bad seeing condition than a small scope. True for any large scope. I have been lucky enough to observe in sub-arc-second seeing conditions a few times. Not on this continent. Best detail view I have ever had of anything. Made Astro photos seem lame. It was through a 22UC. The build quality has not presented any issues with my scope. Especially seeing the number of miles, it has had bouncing around in the trailer. The overall design has also turned out to my liking and don¡¯t see any issues. I did make a few mods like different assembly bolts to speed up assembly in the dark.? That¡¯s my experiences with the UC line of telescopes. Bob Rose ¡°Have scope, Will Travel¡± ? ? ? ? I've logged hundreds of hours and seen thousands of objects with the UC18 since I purchased it from Dave Krieg in 2009 and have been very happy with it.? I use it in "push to" mode with the Argo Navis and digital encoders, so have no experience with servo cat.? Lately, I've been linking it to my iPad and Sky Safari, which also works well.? The lighter but more portable UC design is clearly a trade off with the stability of the larger and heavier classic design.? Living in the burbs under a canopy of 100 foot tall oaks and street lights, I need a portable scope, and the classic is just too much work (heavy and bulky) for me to comfortably transport 50 miles to a dark site when we have a clear moonless night.? For the ease of transportation and assembly that the UC provides, I gladly live with the need to collimate the scope before every use, and with its tendency to lose collimation under certain observing conditions.? I've done a lot of reading on collimation and have become pretty handy with lasers and other collimation tools. ? But even then, the collimation of my UC is rarely the limiting factor when doing visual observing.? The atmospheric seeing and my imperfect eyes are usually where I hit the stops.? And even though I have concentrated on faint fuzzies in the deep sky where the collimation of the UC is not critical, I also regularly check out the planets and, on occasion have been rewarded with HD quality views of Jupiter and Saturn.? I've been observing for almost 50 years and can safely say that the views offered by the 18UC far surpass anything I've ever had with any other scope.? This isn't to say there aren't better scopes out there, just that the 18UC is an awesome instrument when used within its limits.? Over the years I've supplemented my UC18 with a 5" ED refractor on a GotTo mount for planetary observing, and a star tracker mount for my Canon digital camera, all of which complement each other very nicely I think.? At least, I'm never bored.? I hope to move out of the city and get a 25" classic when I retire.? Now that would truly be AWESOME!
Bob Gardner
Falls Church, VA
?
|
Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
What I did was to get longer thumb-bolts and take about ?¡± of thread off of them. Round then slightly on the end. Makes it easy for them find the holes and make it tough to cross thread. I stole the idea from distance auto racing. ?F1 just has one big bolt that the wheel/nut goes over where NASCAR has a bunch. Bob ?
toggle quoted message
Show quoted text
From: [email protected] < [email protected]> On Behalf Of Christine Zeltner Sent: Sunday, October 17, 2021 10:01 AM To: [email protected]Subject: Re: [ObsessionUsers] Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer? ? bobrose500 What assembly bolts did you change to? ? I have had a UC22 since 2010 and have no real issues with it. Any collimations issues I have had were self-inflicted. Example: I recently attended the OKieTex Star Party. 1st observable night, Set, up collimated, and observed until about 3:30or so. 2nd night checked collimation and it was off slightly. Found one truss pole that I had not fully tighten. Tweaked the collimation and had an awesome night. Rest of the nights checked collimation and found the donut centered. I use the Barlow laser method. This scope has Argo Navis and no ServoCat. My previous scope was a 20¡± f5 classic that I had added the ServoCat on then about a 12-year-old scope. It was a great scope with few issues. I found that I used the drives so very little, that I did not even consider getting them on the UC. I have a scope trailer that the 22UC lives in and have roughly calculated the milage of travels with that scope is over 20,000 miles. I show wear and tear about what would be expected. I have observed through 15 UC and 18UC¡¯s including UC#1. Never really saw any real issues with them. I have funny antidote about the 15UC that if you get around me to tell. Involves a person shaking it to see how collimation held up. I elected to go with the 22 and sell the 20 because of less weight and less ladder. I am getting older. I think a lot of collimation issues are because of bad seeing and not bad optical system. Large scopes are going to collect and amplify more of the bad seeing condition than a small scope. True for any large scope. I have been lucky enough to observe in sub-arc-second seeing conditions a few times. Not on this continent. Best detail view I have ever had of anything. Made Astro photos seem lame. It was through a 22UC. The build quality has not presented any issues with my scope. Especially seeing the number of miles, it has had bouncing around in the trailer. The overall design has also turned out to my liking and don¡¯t see any issues. I did make a few mods like different assembly bolts to speed up assembly in the dark.? That¡¯s my experiences with the UC line of telescopes. Bob Rose ¡°Have scope, Will Travel¡± ? ? ? ? I've logged hundreds of hours and seen thousands of objects with the UC18 since I purchased it from Dave Krieg in 2009 and have been very happy with it.? I use it in "push to" mode with the Argo Navis and digital encoders, so have no experience with servo cat.? Lately, I've been linking it to my iPad and Sky Safari, which also works well.? The lighter but more portable UC design is clearly a trade off with the stability of the larger and heavier classic design.? Living in the burbs under a canopy of 100 foot tall oaks and street lights, I need a portable scope, and the classic is just too much work (heavy and bulky) for me to comfortably transport 50 miles to a dark site when we have a clear moonless night.? For the ease of transportation and assembly that the UC provides, I gladly live with the need to collimate the scope before every use, and with its tendency to lose collimation under certain observing conditions.? I've done a lot of reading on collimation and have become pretty handy with lasers and other collimation tools. ? But even then, the collimation of my UC is rarely the limiting factor when doing visual observing.? The atmospheric seeing and my imperfect eyes are usually where I hit the stops.? And even though I have concentrated on faint fuzzies in the deep sky where the collimation of the UC is not critical, I also regularly check out the planets and, on occasion have been rewarded with HD quality views of Jupiter and Saturn.? I've been observing for almost 50 years and can safely say that the views offered by the 18UC far surpass anything I've ever had with any other scope.? This isn't to say there aren't better scopes out there, just that the 18UC is an awesome instrument when used within its limits.? Over the years I've supplemented my UC18 with a 5" ED refractor on a GotTo mount for planetary observing, and a star tracker mount for my Canon digital camera, all of which complement each other very nicely I think.? At least, I'm never bored.? I hope to move out of the city and get a 25" classic when I retire.? Now that would truly be AWESOME!
Bob Gardner
Falls Church, VA
?
|
Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
bobrose500
What assembly bolts did you change to?
Chris
I have had a UC22 since 2010 and have no real issues with it. Any collimations issues I have had were self-inflicted. Example: I recently attended the OKieTex Star Party. 1st observable night, Set, up collimated, and observed until about 3:30or so. 2nd night checked collimation and it was off slightly. Found one truss pole that I had not fully tighten. Tweaked the collimation and had an awesome night. Rest of the nights checked collimation and found the donut centered. I use the Barlow laser method. This scope has Argo Navis and no ServoCat. My previous scope was a 20¡± f5 classic that I had added the ServoCat on then about a 12-year-old scope. It was a great scope with few issues. I found that I used the drives so very little, that I did not even consider getting them on the UC. I have a scope trailer that the 22UC lives in and have roughly calculated the milage of travels with that scope is over 20,000 miles. I show wear and tear about what would be expected. I have observed through 15 UC and 18UC¡¯s including UC#1. Never really saw any real issues with them. I have funny antidote about the 15UC that if you get around me to tell. Involves a person shaking it to see how collimation held up. I elected to go with the 22 and sell the 20 because of less weight and less ladder. I am getting older. I think a lot of collimation issues are because of bad seeing and not bad optical system. Large scopes are going to collect and amplify more of the bad seeing condition than a small scope. True for any large scope. I have been lucky enough to observe in sub-arc-second seeing conditions a few times. Not on this continent. Best detail view I have ever had of anything. Made Astro photos seem lame. It was through a 22UC. The build quality has not presented any issues with my scope. Especially seeing the number of miles, it has had bouncing around in the trailer. The overall design has also turned out to my liking and don¡¯t see any issues. I did make a few mods like different assembly bolts to speed up assembly in the dark.? That¡¯s my experiences with the UC line of telescopes. Bob Rose ¡°Have scope, Will Travel¡± ? ? ? ? I've logged hundreds of hours and seen thousands of objects with the UC18 since I purchased it from Dave Krieg in 2009 and have been very happy with it.? I use it in "push to" mode with the Argo Navis and digital encoders, so have no experience with servo cat.? Lately, I've been linking it to my iPad and Sky Safari, which also works well.? The lighter but more portable UC design is clearly a trade off with the stability of the larger and heavier classic design.? Living in the burbs under a canopy of 100 foot tall oaks and street lights, I need a portable scope, and the classic is just too much work (heavy and bulky) for me to comfortably transport 50 miles to a dark site when we have a clear moonless night.? For the ease of transportation and assembly that the UC provides, I gladly live with the need to collimate the scope before every use, and with its tendency to lose collimation under certain observing conditions.? I've done a lot of reading on collimation and have become pretty handy with lasers and other collimation tools. ? But even then, the collimation of my UC is rarely the limiting factor when doing visual observing.? The atmospheric seeing and my imperfect eyes are usually where I hit the stops.? And even though I have concentrated on faint fuzzies in the deep sky where the collimation of the UC is not critical, I also regularly check out the planets and, on occasion have been rewarded with HD quality views of Jupiter and Saturn.? I've been observing for almost 50 years and can safely say that the views offered by the 18UC far surpass anything I've ever had with any other scope.? This isn't to say there aren't better scopes out there, just that the 18UC is an awesome instrument when used within its limits.? Over the years I've supplemented my UC18 with a 5" ED refractor on a GotTo mount for planetary observing, and a star tracker mount for my Canon digital camera, all of which complement each other very nicely I think.? At least, I'm never bored.? I hope to move out of the city and get a 25" classic when I retire.? Now that would truly be AWESOME!
Bob Gardner
Falls Church, VA
?
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Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
I have had a UC22 since 2010 and have no real issues with it. Any collimations issues I have had were self-inflicted. Example: I recently attended the OKieTex Star Party. 1st observable night, Set, up collimated, and observed until about 3:30or so. 2nd night checked collimation and it was off slightly. Found one truss pole that I had not fully tighten. Tweaked the collimation and had an awesome night. Rest of the nights checked collimation and found the donut centered. I use the Barlow laser method. This scope has Argo Navis and no ServoCat. My previous scope was a 20¡± f5 classic that I had added the ServoCat on then about a 12-year-old scope. It was a great scope with few issues. I found that I used the drives so very little, that I did not even consider getting them on the UC. I have a scope trailer that the 22UC lives in and have roughly calculated the milage of travels with that scope is over 20,000 miles. I show wear and tear about what would be expected. I have observed through 15 UC and 18UC¡¯s including UC#1. Never really saw any real issues with them. I have funny antidote about the 15UC that if you get around me to tell. Involves a person shaking it to see how collimation held up. I elected to go with the 22 and sell the 20 because of less weight and less ladder. I am getting older. I think a lot of collimation issues are because of bad seeing and not bad optical system. Large scopes are going to collect and amplify more of the bad seeing condition than a small scope. True for any large scope. I have been lucky enough to observe in sub-arc-second seeing conditions a few times. Not on this continent. Best detail view I have ever had of anything. Made Astro photos seem lame. It was through a 22UC. The build quality has not presented any issues with my scope. Especially seeing the number of miles, it has had bouncing around in the trailer. The overall design has also turned out to my liking and don¡¯t see any issues. I did make a few mods like different assembly bolts to speed up assembly in the dark.? That¡¯s my experiences with the UC line of telescopes. Bob Rose ¡°Have scope, Will Travel¡± ? ? ?
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From: [email protected] < [email protected]> On Behalf Of Bob 1 via groups.io Sent: Sunday, October 17, 2021 7:55 AM To: [email protected]Subject: Re: [ObsessionUsers] Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer? ? I've logged hundreds of hours and seen thousands of objects with the UC18 since I purchased it from Dave Krieg in 2009 and have been very happy with it. ?I use it in "push to" mode with the Argo Navis and digital encoders, so have no experience with servo cat. ?Lately, I've been linking it to my iPad and Sky Safari, which also works well. ?The lighter but more portable UC design is clearly a trade off with the stability of the larger and heavier classic design. ?Living in the burbs under a canopy of 100 foot tall oaks and street lights, I need a portable scope, and the classic is just too much work (heavy and bulky) for me to comfortably transport 50 miles to a dark site when we have a clear moonless night. ?For the ease of transportation and assembly that the UC provides, I gladly live with the need to collimate the scope before every use, and with its tendency to lose collimation under certain observing conditions. ?I've done a lot of reading on collimation and have become pretty handy with lasers and other collimation tools. ? But even then, the collimation of my UC is rarely the limiting factor when doing visual observing. ?The atmospheric seeing and my imperfect eyes are usually where I hit the stops. ?And even though I have concentrated on faint fuzzies in the deep sky where the collimation of the UC is not critical, I also regularly check out the planets and, on occasion have been rewarded with HD quality views of Jupiter and Saturn. ?I've been observing for almost 50 years and can safely say that the views offered by the 18UC far surpass anything I've ever had with any other scope. ?This isn't to say there aren't better scopes out there, just that the 18UC is an awesome instrument when used within its limits. ?Over the years I've supplemented my UC18 with a 5" ED refractor on a GotTo mount for planetary observing, and a star tracker mount for my Canon digital camera, all of which complement each other very nicely I think. ?At least, I'm never bored. ?I hope to move out of the city and get a 25" classic when I retire. ?Now that would truly be AWESOME!
Bob Gardner
Falls Church, VA
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Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
I've logged hundreds of hours and seen thousands of objects with the UC18 since I purchased it from Dave Krieg in 2009 and have been very happy with it. ?I use it in "push to" mode with the Argo Navis and digital encoders, so have no experience with servo cat. ?Lately, I've been linking it to my iPad and Sky Safari, which also works well. ?The lighter but more portable UC design is clearly a trade off with the stability of the larger and heavier classic design. ?Living in the burbs under a canopy of 100 foot tall oaks and street lights, I need a portable scope, and the classic is just too much work (heavy and bulky) for me to comfortably transport 50 miles to a dark site when we have a clear moonless night. ?For the ease of transportation and assembly that the UC provides, I gladly live with the need to collimate the scope before every use, and with its tendency to lose collimation under certain observing conditions. ?I've done a lot of reading on collimation and have become pretty handy with lasers and other collimation tools. ? But even then, the collimation of my UC is rarely the limiting factor when doing visual observing. ?The atmospheric seeing and my imperfect eyes are usually where I hit the stops. ?And even though I have concentrated on faint fuzzies in the deep sky where the collimation of the UC is not critical, I also regularly check out the planets and, on occasion have been rewarded with HD quality views of Jupiter and Saturn. ?I've been observing for almost 50 years and can safely say that the views offered by the 18UC far surpass anything I've ever had with any other scope. ?This isn't to say there aren't better scopes out there, just that the 18UC is an awesome instrument when used within its limits. ?Over the years I've supplemented my UC18 with a 5" ED refractor on a GotTo mount for planetary observing, and a star tracker mount for my Canon digital camera, all of which complement each other very nicely I think. ?At least, I'm never bored. ?I hope to move out of the city and get a 25" classic when I retire. ?Now that would truly be AWESOME!
Bob Gardner
Falls Church, VA
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Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
Collimation was never an issue with my UC-22. It was the implementation of the drive and lousy engineering and build quality. It works now, mostly, but for $15k I did not expect a darn ATM project. And as I said, the dentist was ZERO help. You bought it, too bad.
And I did not scold anyone (or did not mean too).
---------------------------------------? Religion... together we can find the cure." - Richard Dawkins
On Saturday, October 16, 2021, 01:38:13 PM PDT, Clifford Barcliff via groups.io <raghauler375@...> wrote:
Searching through various forums over the last few months, in seems to come down to the 3/6 pole design versus 4/8 pole design. ?More attachment points might be leading to a more rigid design. ? The 18 UC UTA ?might be a little too heavy for the 3/6 pole setup.?
I am considering the 15UC as owners of the ?lighter scope haven¡¯t complained about collimating.?
Dark skies.?
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Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
It's been a while since I used my 18UC.? I've developed an interest in video astronomy, where the camera is connected to an 8" scope which reveals a live image of the object on a laptop screen to be live stacked, etc by software - a different experience from the EP completely but you see the result in seconds as the image develops on screen.
For public star parties (pre COVID) I used the 18UC for public outreach, star parties and for personal trips with my Astronomy group to dark sites in years past.
The 18UC + ArgoNavis/ServoCat was perfect for me!? The optics and views were amazing - hands down! I can break the components down and put them in my car - no sweat.? Yes, set up time can be long - but who is in a rush?? Yes, it is not as sturdy as a Classic design and there is a slight collimation drift depending on the scope position - but the views are still magnificent. I am not alone to state this.
So for me, the optics, convenience and aperture offered were the tipping points.
Jim
On Saturday, October 16, 2021, 05:43:23 p.m. EDT, Christine Zeltner <czeltner356@...> wrote:
;I have the 15 UC and am happy with it.? I do not have any of the electronics on it.? It is a bit of a pain to set up but I am 5'5" so one more inch would make a difference.? It is great for straight basic visual observing.
I have not had collimation problems.
Chris
On Sat, Oct 16, 2021 at 3:38 PM Clifford Barcliff via <raghauler375= [email protected]> wrote: Searching through various forums over the last few months, in seems to come down to the 3/6 pole design versus 4/8 pole design.? More attachment points might be leading to a more rigid design. ? The 18 UC UTA ?might be a little too heavy for the 3/6 pole setup.?
I am considering the 15UC as owners of the ?lighter scope haven¡¯t complained about collimating.?
Dark skies.?
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Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
Our Club owns the Obsession 18" UC... great scope, but not on a windy night...it gets pushed around by the wind. Greg W
;I have the 15 UC and am happy with it.? I do not have any of the electronics on it.? It is a bit of a pain to set up but I am 5'5" so one more inch would make a difference.? It is great for straight basic visual observing.
I have not had collimation problems.
Chris
On Sat, Oct 16, 2021 at 3:38 PM Clifford Barcliff via <raghauler375= [email protected]> wrote: Searching through various forums over the last few months, in seems to come down to the 3/6 pole design versus 4/8 pole design.? More attachment points might be leading to a more rigid design. ? The 18 UC UTA ?might be a little too heavy for the 3/6 pole setup.?
I am considering the 15UC as owners of the ?lighter scope haven¡¯t complained about collimating.?
Dark skies.?
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Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
;I have the 15 UC and am happy with it.? I do not have any of the electronics on it.? It is a bit of a pain to set up but I am 5'5" so one more inch would make a difference.? It is great for straight basic visual observing.
I have not had collimation problems.
Chris
On Sat, Oct 16, 2021 at 3:38 PM Clifford Barcliff via <raghauler375= [email protected]> wrote: Searching through various forums over the last few months, in seems to come down to the 3/6 pole design versus 4/8 pole design.? More attachment points might be leading to a more rigid design. ? The 18 UC UTA ?might be a little too heavy for the 3/6 pole setup.?
I am considering the 15UC as owners of the ?lighter scope haven¡¯t complained about collimating.?
Dark skies.?
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Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
Searching through various forums over the last few months, in seems to come down to the 3/6 pole design versus 4/8 pole design. ?More attachment points might be leading to a more rigid design. ? The 18 UC UTA ?might be a little too heavy for the 3/6 pole setup.?
I am considering the 15UC as owners of the ?lighter scope haven¡¯t complained about collimating.?
Dark skies.?
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Re: Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer?
I went to the Web site today and it appears that classics up to 20" are still for sale there. Is this an error? Does the Obsession Web site not reflect (no pun intended) current reality?
Chas. (Still hoping to buy a Classic in the near future...)
On Saturday, October 16, 2021, 11:44:02 AM EDT, Johnie Scofield <bandjinpnx@...> wrote:
I don't think I have every knocked any product on-line. But my advise and experience is the same. The UC has serious design issues an is a real pian to set up and keep in good condition. Buy an used standard model if it is to be an Obsession. I ending up buying another quality 18" ( no product plugs and he is no longer making them now) and am SUPER happy. My UC18 .... I am strongly contemplating cannibalizing it and making a lightweight of my own. Not knocking Obsessions .... just the UC design.
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I?WOULD NOT?repeat?WOULD NOT?buy any Obsession UC product.? I own one of the ?18 UC models fabricated in 2017, the optics are great, as long as you don¡¯t move the scope back and forth across the sky more than once or twice in a night.? IT CANNOT HOLD COLLIMATION for crap.? I have had it looked at buy many folks.? Krieg admitted that it is a poor design for ServoCat due to the stress that the ServoCat places on the bearings.? I ended up buying a used CLASSIC obsession 20¡± from Astromart. AMEN BROTHER. Except you got him to talk. I got NOTHING from him. The UCs are a RIPOFF.
But if ANYONE wants to come to Southern California, I'd be happy to sell my UC-22 with servocat for 10,500 USD. Not a penny less.? That is 4k less than I paid.? I'd write that off as an expensive lesson.
The classics are a completely different animal. And as I have said, I trade one for one for a 20 with drive. Just have to come here, or within a few 200 miles.
---------------------------------------? Jeff Gortatowsky Religion... together we can find the cure." - Richard Dawkins
On Friday, October 15, 2021, 08:11:11 PM PDT, charles jagow <chuck@...> wrote:
Webster has been out of business for a while.? Take a look at New Moon telescopes in Virginia, Teeter scopes, and Star Structure ? I WOULD NOT repeat WOULD NOT buy any Obsession UC product.? I own one of the ?18 UC models fabricated in 2017, the optics are great, as long as you don¡¯t move the scope back and forth across the sky more than once or twice in a night.? IT CANNOT HOLD COLLIMATION for crap.? I have had it looked at buy many folks.? Krieg admitted that it is a poor design for ServoCat due to the stress that the ServoCat places on the bearings.? I ended up buying a used CLASSIC obsession 20¡± from Astromart. ? I spoke with Dave K. at length concerning my UC18, and he was at a total loss and just apologized.? His only reasoning for continuing the UC scope is that they are ¡°easier¡± to fabricate and take less time and effort, plus they are the ¡°techie¡± kind of thing.? Since Dave is a Dentist by trade and started the Obsession line as a side, I think he is trying to minimize a bit.? I will never buy another Obsession product unless he starts producing the Classic design again. ? When I can scrape the $$$ together I will have New Moon telescopes build me an 18¡± scope with no optics, focuser etc and then migrate the guts of the 18UC to the new hull.? But I am enjoying my new-to-me 20¡± Classic, had it four months now and have only collimated ONCE when I first put it together.? I roll it out of the garage and about 50¡¯ down my somewhat bumpy driveway three or four times a week to view. ?Even though I must use my ladder to set the 20¡± up, it takes less time to set up than the 18UC, about fifteen minutes or so. ? Sorry there is not better news about the UC line of scopes.? But the ultimate in portability (fit in an airline packing crate) comes at a cost of stability.? Sure, there are people who will rave about how much they ¡°love¡± their UC, but how many people will admit they made a $10K mistake?? I now know four others who bought 18UC and 22 UC scopes and dumped them on Astromart within six months due their inability to maintain collimation. ? ? From:<[email protected]> on behalf of Christine Zeltner <czeltner356@...>
Reply-To: <[email protected]>
Date: Friday, October 15, 2021 at 2:44 PM
To: <[email protected]>
Subject: Re: [ObsessionUsers] Wanted: Alternative to Obsession's 20" "Classic" Dobsonian: 22" UC or Alternative Manufacturer? There is Webster Telescopes, New Moon and a couple more I cannot remember. I have the 15 UC and love it but it really needs a level surface. ? I screwed up.? I procrastinated for years.? Now that I am finally ready to purchase a new 20¡± ¡°Classic¡± Obsession telescope, I have learned that this telescope no longer is made.? I confirmed that directly with Dave Kriege of Obsession Telescopes in August.? He recommended its 22¡± ¡°Ultra-Compact¡± ¡®scope.? But states that the ¡°classic¡± design is more stable than the ¡°ultra-compact¡± design. ? Two questions: ? #1:? Any owners of Obsession¡¯s 22¡± ¡°ultra compact¡± telescope on this forum?? If so, any regrets or recommendations?? And if you have the complete ¡°go-to¡± and digital setting circles set-up, are you happy with it? ? #2:? Can any of you recommend an alternative manufacturer of a large aperture (>18¡±) Dobsonian telescope constructed similarly to how Obsession¡¯s ¡°classic¡± telescopes are/were made?? I can tolerate the bulk of such a design to gain better stability. ? Any suggestions or recommendations will be greatly appreciated.? Thanks in advance. ? Mark in California (Without a telescope since spring 2020.? It¡¯s killing me.)
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Jesse Godsey
Greg Wing
Christine Zeltner
¹ó°ù¨¦»å¨¦°ù¾±³¦ Ruciak
bobrose500