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I really hate my Bird-Jones and can't collimate it - help!

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#1 jgroub

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Posted 24 October 2014 - 02:42 AM

As my signature shows, I have a Meade DS-2130AT.  This is a 5.1-inch short-tube spherical newtonian with a Bird-Jones corrector.  I am very frustrated by being completely unable to collimate the **** thing.  And this has led me to think that the scope is a just a gigantic, utterly useless piece of junk anyway.  

 

I have seen some collimation tips for a B-J where they say that the first step is to take off the B-J lens, and to do that, you have to completely disassemble the focuser.  I'm sorry, but that just ain't happening.  Number one, I feel very uncomfortable taking apart the scope:  the focuser, the spider, etc.  Number two, I just ain't that handy, so I feel like I will bust the thing up or not be able to put it back together again without screwing things up royally.  So, please don't tell me "No, it'll be okay; just take it apart."  You have to understand that I am simply not capable of doing that.  No way.  There has to be some other way.  

 

Another thing is that I have no spatial conception ability whatsoever.  Honestly, when I took the "folding the boxes" test in 6th grade, I scored in the 4th percentile - I'm that lame.  Even with something as simple as aligning the secondary, I screw that up too - when I mess with the three screws, I have no idea what I'm doing, I can't get the stupid mirror in the right place, and I get very frustrated very quickly.  I have a complete lack of mechanical aptitude.  

 

I understand that a laser collimator doesn't work on a B-J scope.  Not really a problem, since I don't have one.  The scope also didn't come with a collimation cap OR a cheshire.  And, of course, there is no center spot on the mirror.  And, again, I have no confidence in my ability to take the telescope apart by removing the mirror to put a spot on it.  However, if you can honestly tell me, "Yes, even though your scope is generally a POS, if you can get it collimated well, it will be decent," then I will be happy to spend the money to get some sort of collimation tool other than a laser.  

 

There has got to be another way to collimate a B-J scope without taking everything apart.  Is there a guide or a video online somewhere?  I have looked, and other than a video on collimating a Celestron B-J, I haven't been able to find one that doesn't start out with "remove the B-J lens."  Maybe there's somewhere I can go where they'll teach me how to do it?  Local star parties have been getting called recently over and over again for the past month because of clouds.  

 

Since I'm in Manhattan, can I just take it over to Adorama or B&H Photo or somewhere else and have them collimate the **** thing for me?  I'll pay!!!  Who should I ask for over there?  

 

Or if not, should I just take a walk on the Brooklyn Bridge and pitch it over the side?  Or would you suggest the George Washington Bridge instead?  I wouldn't mind doing that, trust me.  I feel like I wouldn't want to torture someone else by passing this POS along to them.  

 

And second question - I would love to just forget this whole scope and buy an 8-inch dob instead.  Someone please tell me that a normal, regular old dob is easier to collimate.  I've watched a bunch of videos, and it just doesn't look too hard.  I think even an uncoordinated putz like me could do what I see in the videos.  But be honest with me - if I am unable to collimate this, does that sink my hopes for being able to collimate a dob?  Should I just buy a refractor instead and be done with this whole collimation business?  

 

What do you think?  Help me, Obi-Wan, you're my only hope!  


Edited by jgroub, 24 October 2014 - 03:42 AM.


#2 howard929

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Posted 24 October 2014 - 06:00 AM

Hmmm...   you sound like a refractor type guy to me. Nice ones are a bit pricey but nothing wrong with that.


Edited by howard929, 24 October 2014 - 06:01 AM.


#3 catboat

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Posted 24 October 2014 - 06:24 AM

 

 

What do you think?  Help me, Obi-Wan, you're my only hope!  

 

While waIting for Obi-Wan, here's my take:

 

Yes, the B-J scope you have is likely to be a POS.  No, don't throw it off any of the Manhattan bridges -- that's illegal.  Find a small bridge out in the country.   :)   Or any trash can will do. 

 

Or give it away.

 

A typical newtonian is relatively easy to collimate, but I tend to agree with the previous post that reflectors probably aren't your thing.  All reflectors need mechanical attention.  A reflector is a tinkerer's dream.  A life-time of fiddling fun.  If you don't want to analyze components and take corrective measures with screwdriver in hand, then I'd cross newtonians off the list.  Besides, an 8" dob is a sizable scope for a city-dweller.  

 

I'd look for a small refractor -- or a small SCT or MakCass (where the tinkering possibilities are limited if you get a good one out of the box   -- collimation excepted).  These will be much easier to transport and use with a minimum of fuss.


Edited by catboat, 24 October 2014 - 06:35 AM.


#4 James1996

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Posted 24 October 2014 - 06:25 AM

Hmm I agree with howard you sound like a refractor type of guy. That said I am not sure what to suggest to you. Perhaps someone with more experience can help you.



#5 howard929

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Posted 24 October 2014 - 06:36 AM

Jon,

 

+1 for not dumping it off near any bridge in or near NYC. They have cameras and Home Land Security has nothing better to do then hunt you down. They will find you. Personally, I would beat it to death. With a 2 pound lump hammer but I don't think you have one. Just set it up outside tomorrow then walk away and someone is sure to walk off with it like it belongs to them.

 

Then, buy a nice triplet, a sturdy mount and be prepared to have your socks knocked off. 


Edited by howard929, 24 October 2014 - 06:39 AM.


#6 GlennLeDrew

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Posted 24 October 2014 - 07:00 AM

Before taking drastic action...

 

First thing is to see if the primary is aligned in the ballpark. Look into the front end from fairly close up. You'll see the reflection of your viewing eye. Slowly move your head farther away, while keeping your eye's reflection centered. Keep going until your iris pretty much fills the primary. Keeping your head still, and your iris reflection nicely centered in reflection, ascertain that the spider vanes/secondary support are simultaneously superimposed upon their reflected images.

 

This assumes the spider/secondary holder are centered, with no offset due to the relatively fast f/ratio primary. To verify centration, simply measure opposing distances between tube and vane. If not centered in one or both directions, this *may* require adjusting. But in the meantime, you can tape a couple of centered strings across the front opening, in an X configuration rotated roughly 45 degrees to the vanes. These strings will then be your fiducials, not the vanes/secondary holder.

 

If you do not have the vanes (or strings) nicely superimposed while your reflected iris is centered, the primary probably requires adjustment in tilt. Once this is achieved, you're ready to fiddle with the secondary adjustment. I'll leave it that for now...



#7 Jon Isaacs

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Posted 24 October 2014 - 08:15 AM

 

 

And second question - I would love to just forget this whole scope and buy an 8-inch dob instead.  Someone please tell me that a normal, regular old dob is easier to collimate.  I've watched a bunch of videos, and it just doesn't look too hard.  I think even an uncoordinated putz like me could do what I see in the videos.  But be honest with me - if I am unable to collimate this, does that sink my hopes for being able to collimate a dob?  Should I just buy a refractor instead and be done with this whole collimation business? 

What do you think?  Help me, Obi-Wan, you're my only hope!

 

Hi:

 

This is the way I think about it:

 

I have reasonable collimation skills and a good set of tools. My fastest Newtonian is a 12.5 inch F/4.06 which I have owned for more than 10 years and I have no trouble collimating it.

 

I have owned several Jones-Bird scope, one was a Vixen made in Japan.  I never had much luck collimating Jones-Bird scopes, one can make some improvement but in my experience, it's a compromised design, they are marginal optically You have probably done your best, you have done a reasonable job but the scope will never perform the way a 130mm Newtonian with a parabolic mirror can.  Honestly, I really wish Celestron and Meade would stop selling Jones-Bird scopes.  They do it because they are short so the mount can be smaller than with a standard Newtonian but the standard Newtonian will be a much better performer...  

 

So, in my view, the fact that you are unable to improve the views by collimating your scope is not about your collimation skills but rather about the scope itself.  Accept it for what it is, enjoy what it can do, don't expect it to do anything more.

 

And certainly do not let your difficulties with this scope deter you from thinking you can collimate a 8 inch F/6 Dob.. The skills and understandings you have developed with your 130mm Jones-Bird will serve you well with an 8 inch Dob. Collimation of the Dob is straightforward, the Dobsonian will have good quality optics and will provide clean, sharp views when collimated.  That was just not going to happen with the Jones-Bird no matter what you did.

 

Jon Isaacs 



#8 SpooPoker

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Posted 24 October 2014 - 11:17 AM

I echo Jon's sentiment.  A Newtonian is not hard to collimate.  The Bird Jones design is not user friendly - I often wonder why they even bother.  If a short tube is desirable, the SCT design ticks most boxes.  If manufacturers are that concerned about mounting a short tube reflector on a smaller mount, why not just sell a classical cassegrain?  It for sure would work better than the current BJ designs.  I guess the BJ design is attractive to them because a spherical mirror is also quite straightforward to manufacture.

 

I do not suggest junking the scope.  Use if for what it is and upgrade in due course if you feel inclined to do so.  Donate the scope to Goodwill or sell it when it gets replaced.    Give it some star time.



#9 jgroub

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Posted 24 October 2014 - 12:33 PM

 

 

 

What do you think?  Help me, Obi-Wan, you're my only hope!  

 

While waIting for Obi-Wan, here's my take:

 

Yes, the B-J scope you have is likely to be a POS.  No, don't throw it off any of the Manhattan bridges -- that's illegal.  Find a small bridge out in the country.   :)   Or any trash can will do. 

 

Or give it away.

 

A typical newtonian is relatively easy to collimate, but I tend to agree with the previous post that reflectors probably aren't your thing.  All reflectors need mechanical attention.  A reflector is a tinkerer's dream.  A life-time of fiddling fun.  If you don't want to analyze components and take corrective measures with screwdriver in hand, then I'd cross newtonians off the list.  Besides, an 8" dob is a sizable scope for a city-dweller.  

 

I'd look for a small refractor -- or a small SCT or MakCass (where the tinkering possibilities are limited if you get a good one out of the box   -- collimation excepted).  These will be much easier to transport and use with a minimum of fuss.

 

Wouldn't give it away.  I couldn't do that to someone else.  Well, maybe my old boss, but even then. 

 

How about the Skywatcher Virtuoso Mak?  I've heard really good things about it.  

 

http://www.bhphotovi...tile_mount.html

 

Is it true that you basically NEVER collimate a Mak?  Because that would be the ticket for me.  



#10 spencerj

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Posted 24 October 2014 - 01:48 PM

Wouldn't give it away.  I couldn't do that to someone else.  Well, maybe my old boss, but even then. 

 

 

How about the Skywatcher Virtuoso Mak?  I've heard really good things about it.  

 

http://www.bhphotovi...tile_mount.html

 

Is it true that you basically NEVER collimate a Mak?  Because that would be the ticket for me.  

 

 

I have owned 6 different Maksutovs over the years.  They all required collimation at some point.  If a telescope has mirrors, to get the most out of it, you will have to make adjustments at some point.  If you want a scope that you never have to touch, you want a refractor.  That said, a quality refractor on a mount that will not drive you crazy will cost you a lot more per inch of aperture than a Dobsonian-mounted reflector.

 

As for the scope you linked to . . . I would pass.  A 90mm MCT is a fun scope, but it will be limited by the aperture and the narrow FOV is not for a beginner who is easily frustrated.  Additionally, the table-top goto mount is not going to be a dream setup.  It will not be stable or easy to use and it may not be reliable.  At that price point, what you want is a 6" F8 dob.  At F8, the collimation tolerances are large.  If you are even in the ballpark, the images will be fine.  6" is still a small scope, but it would absolutely kill the 90mm MCT on all objects.



#11 JoeinWV

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Posted 24 October 2014 - 02:53 PM

Try what I did. First, as others have said, make sure secondary is at least centered in focuser tube and you can see the primary mirror.

 

I did take out the correcting lens before, but then it occurred to me, just take the draw tube out that has the lens in it instead. In the case of my Meade 4.5 J-B, way easier!  

Just 2(or 4) screws at the focuser knob, and it comes right out. Making sure not to loose the small tensioner thing that will fall out.

 

Once you pull out the draw tube, collimate it like standard Newtonian, as best you can.

 

Then reassemble, and with a telescope that short, it is super easy to fine tune collimation on a star( like Polaris).


Edited by JoeinWV, 24 October 2014 - 02:55 PM.


#12 Dave Mitsky

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Posted 24 October 2014 - 04:19 PM

Honestly, I really wish Celestron and Meade would stop selling Jones-Bird scopes.  They do it because they are short so the mount can be smaller than with a standard Newtonian but the standard Newtonian will be a much better performer...  

 

That makes two of us.

 

Dave Mitsky



#13 Hesiod

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Posted 24 October 2014 - 05:19 PM

Just to be sure, but have you checked if the scope really need a major collimation adjustment?

 

You may pay someone to do the first collimation, but eventually have to learn do it by yourself because all reflector and reflector-based telescope requires regular trimming (which does not mean that you have to do every time a "big collimation", mostly minor adjustments are enough. In any case the best thing is to CHECK if the telescope needs to be collimated BEFORE start the screwdriver job).

 

Getting a new telescope instead of learning to use the one you have is not imho a real solution: even the Maksutov-Gregory telescopes requires to check and, if the case, adjust the collimation. I have the 90/1250 and check its collimation every time use it; in the last 2 years of gentle handling (i.e. keep always in its padded bag, do not drop/launch/bump/strike)  had to adjust the collimation twice.

The 90/1250 by Synta (like its 5", 6" and 7" siblings) can be collimated only through adjustment of the secondary mirror, and due to a imho really poor engineering, 2 different Allen wrenches are required to perform the task.

 

 

As a side note, the notion that refractors are immune to miscollimation is not really true (even if a miscollimated refractor usually mean that someone did previously some really bad things to it).



#14 Pinbout

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Posted 24 October 2014 - 06:42 PM

 

 

As my signature shows, I have a Meade DS-2130AT.  This is a 5.1-inch short-tube spherical newtonian with a Bird-Jones corrector.  I am very frustrated by being completely unable to collimate the **** thing.  And this has led me to think that the scope is a just a gigantic, utterly useless piece of junk anyway.  

 

I have seen some collimation tips for a B-J where they say that the first step is to take off the B-J lens, and to do that, you have to completely disassemble the focuser.  I'm sorry, but that just ain't happening.  Number one, I feel very uncomfortable taking apart the scope:  the focuser, the spider, etc.  Number two, I just ain't that handy, so I feel like I will bust the thing up or not be able to put it back together again without screwing things up royally.  So, please don't tell me "No, it'll be okay; just take it apart."  You have to understand that I am simply not capable of doing that.  No way.  There has to be some other way.  

 

Another thing is that I have no spatial conception ability whatsoever.  Honestly, when I took the "folding the boxes" test in 6th grade, I scored in the 4th percentile - I'm that lame.  Even with something as simple as aligning the secondary, I screw that up too - when I mess with the three screws, I have no idea what I'm doing, I can't get the stupid mirror in the right place, and I get very frustrated very quickly.  I have a complete lack of mechanical aptitude.  

 

I understand that a laser collimator doesn't work on a B-J scope.  Not really a problem, since I don't have one.  The scope also didn't come with a collimation cap OR a cheshire.  And, of course, there is no center spot on the mirror.  And, again, I have no confidence in my ability to take the telescope apart by removing the mirror to put a spot on it.  However, if you can honestly tell me, "Yes, even though your scope is generally a POS, if you can get it collimated well, it will be decent," then I will be happy to spend the money to get some sort of collimation tool other than a laser.  

 

There has got to be another way to collimate a B-J scope without taking everything apart.  Is there a guide or a video online somewhere?  I have looked, and other than a video on collimating a Celestron B-J, I haven't been able to find one that doesn't start out with "remove the B-J lens."  Maybe there's somewhere I can go where they'll teach me how to do it?  Local star parties have been getting called recently over and over again for the past month because of clouds.  

 

Since I'm in Manhattan, can I just take it over to Adorama or B&H Photo or somewhere else and have them collimate the **** thing for me?  I'll pay!!!  Who should I ask for over there?  

 

Or if not, should I just take a walk on the Brooklyn Bridge and pitch it over the side?  Or would you suggest the George Washington Bridge instead?  I wouldn't mind doing that, trust me.  I feel like I wouldn't want to torture someone else by passing this POS along to them.  

 

And second question - I would love to just forget this whole scope and buy an 8-inch dob instead.  Someone please tell me that a normal, regular old dob is easier to collimate.  I've watched a bunch of videos, and it just doesn't look too hard.  I think even an uncoordinated putz like me could do what I see in the videos.  But be honest with me - if I am unable to collimate this, does that sink my hopes for being able to collimate a dob?  Should I just buy a refractor instead and be done with this whole collimation business?  

 

What do you think?  Help me, Obi-Wan, you're my only hope!  

 

Come to Anthony Wayne recreation center  on the pallisades pkwy 

tomorrow night. RAC is having a joy to the universe thing. It can be fixed. If the weather is clear. ill let you collimate my dob so you can see the difference. :p


Edited by Pinbout, 24 October 2014 - 06:44 PM.


#15 jgroub

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Posted 24 October 2014 - 07:02 PM

Maksutovs require collimation at some point.  If a telescope has mirrors, to get the most out of it, you will have to make adjustments at some point.  If you want a scope that you never have to touch, you want a refractor.  That said, a quality refractor on a mount that will not drive you crazy will cost you a lot more per inch of aperture than a Dobsonian-mounted reflector.

 

As for the scope you linked to . . . I would pass.  A 90mm MCT is a fun scope, but it will be limited by the aperture and the narrow FOV is not for a beginner who is easily frustrated.  Additionally, the table-top goto mount is not going to be a dream setup.  It will not be stable or easy to use and it may not be reliable.  At that price point, what you want is a 6" F8 dob.  At F8, the collimation tolerances are large.  If you are even in the ballpark, the images will be fine.  6" is still a small scope, but it would absolutely kill the 90mm MCT on all objects.

Thanks, but what if I threw in a couple of facts.  First, I'm not exactly a beginner.  Back 35 years ago, when I was a teenager, I had a Criterion RV-6 (f/8) and then a Meade Newtonian (8-inch f/6).  However, either those were much, much better made and didn't come out of collimation, or the amount they did come out of collimation was relatively more meaningless due to the faster focal lengths.  Either way, I never ever heard of collimation back then; didn't even hear of it until I came to these boards a few months ago.   Obviously, no duh, it's a "thing" and it's a very important thing.  So I was not always this frustrated angry guy you see here.   :)

 

And okay, so Maks eventually require collimation, but wouldn't the collimation toleration for an f/13.9 scope be even greater than that for an f/8?  And wouldn't it be mostly collimated coming right out of the factory for quite some time until it "decollimated"?  

 

Next, the Virtuoso mount does have a tripod attachment (female receptor) in the base, so it wouldn't be on a tabletop.  I'd buy a nice tripod to put it on.  It's not too heavy.  

 

And finally, I'm in the light pollution capital of the world here in Manhattan, so I would just be observing the planets/moon - for which I understand the Mak would be a great scope - and some of the brighter/more famous objects like Orion, Ring, Dumbbell, Hercules, Pleiades, Andromeda, etc.  Yeah, since it's portable, I might take it out to my in-laws' place in yellow/green skies and use it there, but it would mostly be used on top of my roof here in the City.  

 

Hey, I'm not trying to convince you for "permission" so you'll "allow" me to buy a Mak.  I'm just wondering if, given this extra info, it makes any difference to your saying not to get a Mak.  If I knew that I could actually collimate a regular newtonian scope, I'd much prefer to buy the Apertura AD8 instead.   :cool:  But no matter what I would get, I'd just be using it as a very casual observer, looking at only the same dozen or DSOs over and over.  



#16 jgroub

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Posted 24 October 2014 - 07:10 PM

Just to be sure, but have you checked if the scope really need a major collimation adjustment?

 

Let me put it this way.  If it didn't need a major collimation adjustment before I started messing with it, it sure needs one now.  

You may pay someone to do the first collimation, but eventually have to learn do it by yourself because all reflector and reflector-based telescope requires regular trimming (which does not mean that you have to do every time a "big collimation", mostly minor adjustments are enough. In any case the best thing is to CHECK if the telescope needs to be collimated BEFORE start the screwdriver job).

 

jgroub, on 24 Oct 2014 - 8:02 PM, said:

It did need to be collimated.  I couldn't get anything in sharp focus with the 9mm.  I was looking at the moon, and although I could see the light and dark and the round edge, I couldn't bring it to a focus no matter how I tried.  With the 26mm, it was in focus, although not exactly sharp.  

 

 

Getting a new telescope instead of learning to use the one you have is not imho a real solution: even the Maksutov-Gregory telescopes requires to check and, if the case, adjust the collimation. I have the 90/1250 and check its collimation every time use it; in the last 2 years of gentle handling (i.e. keep always in its padded bag, do not drop/launch/bump/strike)  had to adjust the collimation twice.

 

Ah, but my understanding is that because of 1) the way Maks are constructed generally, and 2) because they have such very long focal lengths - this one is an f/13.9 - that they are very tolerant of slight miscollimation, so that perhaps this need not be a concern?  I don't know; I'm actually asking you. :confused:  

 

 

The 90/1250 by Synta (like its 5", 6" and 7" siblings) can be collimated only through adjustment of the secondary mirror, and due to a imho really poor engineering, 2 different Allen wrenches are required to perform the task.

 

No, problem there, got plenty of Allen wrenches.  Not sure if I would know what to do with them, though.  

 

 

 

As a side note, the notion that refractors are immune to miscollimation is not really true (even if a miscollimated refractor usually mean that someone did previously some really bad things to it).



#17 GeneT

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Posted 24 October 2014 - 07:57 PM

I have no handy man skills, but find that a traditional Dob and SCT are fairly easy to collimate. I nice 8 inch Celestron NexStar might be a good fit for you. It has a small foot print and is quite easy to load and set up. You will need to give the optics time to cooldown, i.e. reach ambient temperature. A 6 or 8 inch Dob might also be a nice fit for you. 



#18 Pinbout

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Posted 24 October 2014 - 08:25 PM

 

A 6 or 8 inch Dob might also be a nice fit for you.

 

even a 10"

 

http://www.cloudynig...nian/?p=6267168

 

 

med_gallery_106859_3508_43352.jpg



#19 labmand

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Posted 24 October 2014 - 08:30 PM

My bj scope is my worst pyrchase ever, still have it, used it once, tried and tried collimation

Just not good, thought about goodwill, give away or trash it, hoping someday for a recall,

Yea right, it's all shinny and purdy but a complete pos. What was I thinkin???



#20 jgroub

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Posted 24 October 2014 - 08:41 PM

Come to Anthony Wayne recreation center  on the pallisades pkwy tomorrow night. RAC is having a joy to the universe thing. It can be fixed. If the weather is clear. ill let you collimate my dob so you can see the difference. :p

 

 

 

 


 

 

I live in Manhattan - no car!  Just checked Google Maps, and there's no mass transit way to get there, either.  Thanks for the invite, though; I appreciate the offer.  



#21 howard929

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Posted 25 October 2014 - 05:14 AM

Jon,

 

You mentioned that adjusting the secondary screws for tilt was a process that didn't work and made zero sense to you. Also, you're unwilling to remove the primary mirror to center spot it. With the telescope you have I can see how that could be the case with anyone, not just you.

 

I have a different suggestion from the one yesterday. You need to set yourself up for success with any telescope choice. With the one you have now that was never going to happen but we all know that by now. Set that one aside and buy something you can win with. The way to win would cost a bit more then the telescope but winning is all there is.

 

The reason you couldn't be successful with the tilt adjustments was you had nothing to reference them on. Without a center spot on the primary mirror, secondary tilt adjustments are a WAG as best. Same goes for making primary tilt adjustments.

 

Here's what you do IMO. And BTW, I'm only trying to help so read the whole thing rather then just bail when you see it's a dob.

 

Buy yourself a AWB 130 for $200

 

It comes with a center spot. That's half the battle with collimation. Then buy a 1.25" Galtter laser and Tublug. Howie is good guy and lives, works and sells from the Bronx. Shipping to you would be peanuts. Here's how you win with this telescope set-up. 

 

For secondary tilt adjustments you don't need to understand anything at all. Just chuck the laser in the focuser, crank on one of the screws and you'll see exactly what that's doing. It's visual feedback that's immediate and even if it takes a bit of practice, it's fun to do and not hard to get correct.

 

For making primary tilt adjustments, chuck the Tublug in the focuser and the laser in the Tublug. It's just as fun and as easy to do because you'll be able to see the Tublug target window from the back of the telescope while you're making the adjustments. 

 

There are other collimation methods for way less money that you'll read about but most of them aren't intuitive to use. There are also other lasers and ways to collimate but if you just want to win, buy the Glatter tools and the AWB. Last and possibly a further help. I'm 40 miles from you hiding in the foot hills of Long Giland. Other guys are near to you as well. Telephone support is doable. 



#22 Hesiod

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Posted 25 October 2014 - 05:16 AM

"mushy" views does not imply necessarily miscollimation; a lot of entry-level telescopes have some "optical faults" which could lead to the same results.

Anyway, a star test should answer to any doubt.

 

About the Mak-Gregory 90/1250 Synta, is a nice scope but not a Questar for sure. Its focal ratio is around 13 but because this is obtained through amplification by the secondary mirror of a fast primary mirror, it is quite sensible to slight miscollimations like its SCTs "cousins" (here the primary is even faster).

 

Imho the less collimation-sensible telescope is a medium/long focal refractor* (f/10 and more): sadly these are the most cumbersome of all telescopes, and become quickly pricey (if not the optical tube itself, for sure the suitable mount)

 

 

 

 

*a similar f/ Newtonian behaves in a similar way; however because they are easier to collimate (=there is a quick and convenient way to adjust the collimation) the chance of a mirror misalignement is greater. In any case mid f/ Newtonians are even rarer than slow refractors...the best of them is imho the 150/1200: decent aperture, low obstruction, and -if purchased the Dobsonian version, stable, light and comfortable to use. Bad "balcony telescope" however, as most Dobsonians are...



#23 schang

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Posted 25 October 2014 - 08:24 AM

I think that Synta's Virtuoso Mak-Cass is very similar to the Celestron C90 Mak-Cass I have..They have the same spec.   I have owned the C90 for over a year and have not noticed any image softening that requires collimation. In fact, there is no knobs or screws that allow one to do that.  Jon, in your location with light pollution, this very portable scope is an ideal grab-and go scope for planets, moon, double stars, and some bright DSOs.  I have seen threads about this scope here with a lot of praises, and mine certainly is very sharp.  I can not speak for the particular one from Synta, but you do have 30 days return period that you can try it out if you like its portability. Good luck. 


Edited by schang, 25 October 2014 - 08:25 AM.


#24 backwoody

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Posted 25 October 2014 - 09:22 AM

This will be another story of difficulty.  

 

Years ago, I received a Meade DS 2130 as a gift from my family.  I had high hopes for the "go to" function and the built-in tracking capability, but found the scope required an inordinate amount of "fiddling."  Aligning it required more astro knowledge than beginners typically possess, and even when properly aimed and focused on astronomical targets, the views were disappointing.  Better eyepieces made no difference.  

 

As you've discovered, precise collimation is not possible with these B-J scopes, short of disassembling them.  I quickly concluded my DS 2130 was a waste of time and money.

 

But of course, I would never tell my family that.  Instead, I thanked everyone enthusiastically for a wonderful gift, as it re-ignited my long time interest in the hobby.  I set out designing a larger dob - one that I could tinker with, and use effectively to view so many things in night skies.

 

The Meade DS 2130 went away in a yard sale.

 

Edit: forgot to offer a recommendation:  think about an 80-100mm refractor.  You would really enjoy one.


Edited by backwoody, 25 October 2014 - 09:24 AM.


#25 backwoody

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Posted 25 October 2014 - 02:45 PM

Jon, another thought:  even a good "spotting scope" would please you more than the Meade Bird-Jones DS2130.  Stop by one of the major retailers in NYC (Adorama, B&H, etc.) and check them out.  Pentax and other brands make nice ones, some come with a suitable tripod/mount.

 

Good luck,




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