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24" f/2.75

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#26 Mike Lockwood

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Posted 03 August 2017 - 07:52 PM

Bob, all my optics that you referred to, and Ed's, were made and tested in exactly the same manner.  In the lab, they all test quite similarly, and the very small differences between should not be visible under the sky at focus.  So, differences in performance are due to other factors like mirror cooling, mirror support, collimation, different exit pupils, whether or not a secondary is pinched or the heater is turned up too high, and etc.  I note that one telescope you mentioned had a cooling fan, while at least one other was built by someone who did not like fans at all.  Also, your testing was before we devised the whiffletree and roller edge support, so in some cases performance can actually depend on the altitude the telescope was last used at, or when the mirror was last pushed away from the edge supports!

 

I like your method of testing via looking at the sharpness of focus and tightness of stars - this is how I advise "star testing" because looking at defocused images of large mirrors is often/usually not a dependable method for mirror testing due to the unknown thermal state of a primary.

 

Back to Ed's 24" f/2.75 - it has the whiffletree/roller edge support, as implemented in an Aurora Precision cell.  He used a very carefully tested and constructed cooling system that he will have to describe.  It's impressive.


Edited by Mike Lockwood, 03 August 2017 - 07:52 PM.

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#27 starzonesteve

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Posted 03 August 2017 - 10:01 PM

There are many, many aspects of this telescope that are simply mind blowing. Of course the idea that you can view sitting/flat footed through a 24" scope is incredible.

 

The other game changing aspect is a telescope that is intended for mobility yet throws caution to the wind where weight is concerned. The fact that there is automated mobility using a detachable base is a quantum leap in my mind. It opens up a slew of possibilities for those who don't have the option of using a permanent observatory.

 

Kudos to all involved in the creation of this masterpiece. This is a good time to be in amateur astronomy!



#28 phonehome

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Posted 03 August 2017 - 10:55 PM

Hi folks,

 

Elvira's owner/builder Ed here.  Although my schedule is jammed I will try and answer as many questions as time will allow. Please be civil and constructive in your posts.  I am working on an article for posting on Mr. Lockwood's website that will provide more detail of the build with "glam" pictures and will post notice here when it is up.  I want to thank the following, in no particular order, for their direct or virtual assistance that without would have been an impossible project:  Mike Lockwood, Mel Bartels, Dan Gray (SiTech), Randy (Astrosystems), Nate (Aurora Precision), Howard Banich & Tom Osypowski for added inspiration, Kris (my local CNC shop), Mike (my powdercoater) and Jim (aluminum welder extraordinaire).  There are others so if I missed you let me know.  Thanks again guys.

 

For those of us old enough to remember, Elivra was a Friday night TV personality sensation in the 80's with the subtitle: "Mistress of the Dark".  Her hourglass figure, "valley girl" meets Morticia stick, double-entendre and self-deprecating humor were some of her character's most memorable hallmarks.  For many, myself included, she was quite the temptress and with this nightly passion of ours using her name just somehow seemed appropriate.

 

Why design & build something with these optics and which obviously bucks the trend of lighter construction?  

 

It starts with my particular home locale: a reasonably dark site with decent transparency but unfortunately saddled with terrible seeing conditions most of the time due to nearby mountains, windy (a lot) and loads of agricultural & dirt road dust.  Fortunately, seeing conditions are on occasion, and usually without much notice, steady for short periods of time. Since Elvira was to be kept in the garage, I simply wanted a deep sky/richfield instrument with moderate light-gathering ability that could be deployed quickly and easily, and be put away the same.  So when the transport & support unit concept was entertained it allowed reshuffling of the design/build priority list, moving instrument weight from near the top to near the bottom, which in-turn enabled many of the design features to be incorporated.  I'll just borrow and twist a line from the great Stan Lee: "with great weight comes great stability".  So with mass, a low/short profile due to a fast-ratio primary and a locking electronic clutch system operation in a breeze is well, now a breeze.    Two other major design constraints at the top of the list were: eyepiece height...I'm uncomfortable with ladders after dark especially after I assisted in a public outreach event a few years back where a visitor [not at my scope], viewing through a StarSplitter fell 3-1/2' off a ladder+platform [with handrail !!] onto pavement breaking an ankle and two fingers.  Must've been some view huh? tongue2.gif  .  Anyway, the second constraint is lifting...I'm not getting any younger and didn't want to lift anything over 40 lbs, especially overhead, even when transporting off-site to a star party. The fast ratio was again an answer to these restrictions.  

 

I'd like to stop a moment and ask: what's up with all this perceived difficulty with collimating fast newts?  Sure tolerances are tighter, flexure must be controlled, etc. but this is the easiest dob to collimate I've ever worked with regardless of speed.  It's a 10-15 second job and that's after transporting 600 miles in a trailer!  I simply use the late great Howie's laser & aperture reducer plus TuBlug and collimate with the Paracor SIPS left in-place and observe...

 

There are so many aspects to this project I really don't know where to start. Maybe in the next set of posts I'll expand on viewing experiences and thermal strategies.  Since the transport/support unit [partially seen in Tom's photo] garnered the most inquires at the Eden Valley SP I'll start there. It obviously carries Elvira around, cradles, protects and recharges her (automatically if docked or with a cord undocked).  It sports a swing-arm/platform that holds the secondary cage about 9" off the ground when inserting/removing the truss tubes (in lieu of setting the cage on the ground or a table).  It also safely holds the mirror cover during observing. Some interesting tidbits to share regarding the transport unit: range 6-8 miles on level terrain, can recharge Elvira 3 to 4 times (each good for about 3 nights observing) plus some drive-around power before itself needs a charge. Weight is 201 lbs.  Balance is 90% on drive wheels & 10% on casters which translates to a 2/3 drive-wheel to 1/3 caster-wheel weight distribution with Elvira on board.  Loaded, it can climb a 20 degree grade, is ZTR (zero-turn-radius) and fits the bed of a full-size pickup. It has auxiliary ports for running other 12-volt devices including a 12-volt "hair dryer", extra USB charge jacks and carries the truss-tubes stowed horizontally in padded pockets. Confession: at night I double-duty the tube pockets as handy beer...I...mean cupholders.  It has a 25' pull-out AC power cord for automatic & indefinite charging [means no fear of overcharging] of the internal 24-volt 70 Amp-hour SLA system, has red down-facing LED ground-markers, red driving lights,and yes even has a mini-tow hitch for pulling a cart shocked.gif .   To complete the power picture Elvira has USB ports located on the pedestal for tablet charging and uses an internal automatic & indefinite charge Lithium Iron Phosphate 12-volt 180 Watt-Hour system.

 

To explain everything will probably take many posts so please be patient.

 

Ed


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#29 Tyson M

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Posted 03 August 2017 - 11:02 PM

Hi folks,

 

Elvira's owner/builder Ed here.  Although my schedule is jammed I will try and answer as many questions as time will allow. Please be civil and constructive in your posts.  I am working on an article for posting on Mr. Lockwood's website that will provide more detail of the build with "glam" pictures and will post notice here when it is up.  I want to thank the following, in no particular order, for their direct or virtual assistance that without would have been an impossible project:  Mike Lockwood, Mel Bartels, Dan Gray (SiTech), Randy (Astrosystems), Nate (Aurora Precision), Howard Banich & Tom Osypowski for added inspiration, Kris (my local CNC shop), Mike (my powdercoater) and Jim (aluminum welder extraordinaire).  There are others so if I missed you let me know.  Thanks again guys.

 

For those of us old enough to remember, Elivra was a Friday night TV personality sensation in the 80's with the subtitle: "Mistress of the Dark".  Her hourglass figure, "valley girl" meets Morticia stick, double-entendre and self-deprecating humor were some of her character's most memorable hallmarks.  For many, myself included, she was quite the temptress and with this nightly passion of ours using her name just somehow seemed appropriate.

 

Why design & build something with these optics and which obviously bucks the trend of lighter construction?  

 

It starts with my particular home locale: a reasonably dark site with decent transparency but unfortunately saddled with terrible seeing conditions most of the time due to nearby mountains, windy (a lot) and loads of agricultural & dirt road dust.  Fortunately, seeing conditions are on occasion, and usually without much notice, steady for short periods of time. Since Elvira was to be kept in the garage, I simply wanted a deep sky/richfield instrument with moderate light-gathering ability that could be deployed quickly and easily, and be put away the same.  So when the transport & support unit concept was entertained it allowed reshuffling of the design/build priority list, moving instrument weight from near the top to near the bottom, which in-turn enabled many of the design features to be incorporated.  I'll just borrow and twist a line from the great Stan Lee: "with great weight comes great stability".  So with mass, a low/short profile due to a fast-ratio primary and a locking electronic clutch system operation in a breeze is well, now a breeze.    Two other major design constraints at the top of the list were: eyepiece height...I'm uncomfortable with ladders after dark especially after I assisted in a public outreach event a few years back where a visitor [not at my scope], viewing through a StarSplitter fell 3-1/2' off a ladder+platform [with handrail !!] onto pavement breaking an ankle and two fingers.  Must've been some view huh? tongue2.gif  .  Anyway, the second constraint is lifting...I'm not getting any younger and didn't want to lift anything over 40 lbs, especially overhead, even when transporting off-site to a star party. The fast ratio was again an answer to these restrictions.  

 

I'd like to stop a moment and ask: what's up with all this perceived difficulty with collimating fast newts?  Sure tolerances are tighter, flexure must be controlled, etc. but this is the easiest dob to collimate I've ever worked with regardless of speed.  It's a 10-15 second job and that's after transporting 600 miles in a trailer!  I simply use the late great Howie's laser & aperture reducer plus TuBlug and collimate with the Paracor SIPS left in-place and observe...

 

There are so many aspects to this project I really don't know where to start. Maybe in the next set of posts I'll expand on viewing experiences and thermal strategies.  Since the transport/support unit [partially seen in Tom's photo] garnered the most inquires at the Eden Valley SP I'll start there. It obviously carries Elvira around, cradles, protects and recharges her (automatically if docked or with a cord undocked).  It sports a swing-arm/platform that holds the secondary cage about 9" off the ground when inserting/removing the truss tubes (in lieu of setting the cage on the ground or a table).  It also safely holds the mirror cover during observing. Some interesting tidbits to share regarding the transport unit: range 6-8 miles on level terrain, can recharge Elvira 3 to 4 times (each good for about 3 nights observing) plus some drive-around power before itself needs a charge. Weight is 201 lbs.  Balance is 90% on drive wheels & 10% on casters which translates to a 2/3 drive-wheel to 1/3 caster-wheel weight distribution with Elvira on board.  Loaded, it can climb a 20 degree grade, is ZTR (zero-turn-radius) and fits the bed of a full-size pickup. It has auxiliary ports for running other 12-volt devices including a 12-volt "hair dryer", extra USB charge jacks and carries the truss-tubes stowed horizontally in padded pockets. Confession: at night I double-duty the tube pockets as handy beer...I...mean cupholders.  It has a 25' pull-out AC power cord for automatic & indefinite charging [means no fear of overcharging] of the internal 24-volt 70 Amp-hour SLA system, has red down-facing LED ground-markers, red driving lights,and yes even has a mini-tow hitch for pulling a cart shocked.gif .   To complete the power picture Elvira has USB ports located on the pedestal for tablet charging and uses an internal automatic & indefinite charge Lithium Iron Phosphate 12-volt 180 Watt-Hour system.

 

To explain everything will probably take many posts so please be patient.

 

Ed

Awesome report! Please, keep them coming.

 

I shall look forward to them on the Lockwood website- or here if posted. What a project!



#30 mark cowan

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Posted 03 August 2017 - 11:09 PM

Yeah I like the idea of a telescope that can follow you home.  :waytogo:

 

I'd like to stop a moment and ask: what's up with all this perceived difficulty with collimating fast newts?

 

Inadequate structures mostly.  You haven't got that problem.


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#31 Bob S.

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Posted 04 August 2017 - 07:17 AM

Bob, all my optics that you referred to, and Ed's, were made and tested in exactly the same manner.  In the lab, they all test quite similarly, and the very small differences between should not be visible under the sky at focus.  So, differences in performance are due to other factors like mirror cooling, mirror support, collimation, different exit pupils, whether or not a secondary is pinched or the heater is turned up too high, and etc.  I note that one telescope you mentioned had a cooling fan, while at least one other was built by someone who did not like fans at all.  Also, your testing was before we devised the whiffletree and roller edge support, so in some cases performance can actually depend on the altitude the telescope was last used at, or when the mirror was last pushed away from the edge supports!

 

Mike, I understand that differences in scope design will add some amount of variance to the performance of scopes compared with each other. What I do not understand is what empirical evidence you have for saying that mirrors tested in "exactly" the same manner equate to no variability being introduced by the optics and that bench testing negates any differences in a mirror set's performance? Are you suggesting that all of your mirrors have the same conditions for testing, the same testing equipment, the same techniques at time of manufacturer, the same homogeneity qualities, same zonal corrections, same coating thicknesses, etc.? I am not being purposefully argumentative but I don't understand how an optician can say that all of their mirrors should perform similarly and at levels where manufacturing discrepancies are not perceptible to the observer? Especially when we are talking about manufacturing processes and techniques that likely evolve over time.This seems to fly in the face of really knowing what weightings can be assigned to the various components of variability and how this actually translates to the various individual's receptor systems (Steve O'Meara and his legendary eyesight is an example of extreme variability in perceptual abilities). Empirically with a very, very small sample size relatively speaking, I have seen mirrors made by the same manufacturer known for superb mirrors perform slightly differently in the same model of structures. I am not sure how anyone, including an optician, can accurately assign various weightings that would contribute to perceived variability and be able to say categorically that the differences are beyond the threshold of perception?

 

Mike, some of my observations about weightings I think have some validity but before responding to this post, please see a follow-on post that may explain why the two scopes consistently behaved differently. 


Edited by Bob S., 04 August 2017 - 09:16 AM.


#32 cliff mygatt

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Posted 04 August 2017 - 08:55 AM

Ahh, fond memories of Saturday nights and Elvira intoducing the movie!  What a Clevage!



#33 Bob S.

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Posted 04 August 2017 - 09:04 AM

 

Bob, all my optics that you referred to, and Ed's, were made and tested in exactly the same manner.  In the lab, they all test quite similarly, and the very small differences between should not be visible under the sky at focus.  So, differences in performance are due to other factors like mirror cooling, mirror support, collimation, different exit pupils, whether or not a secondary is pinched or the heater is turned up too high, and etc.  I note that one telescope you mentioned had a cooling fan, while at least one other was built by someone who did not like fans at all.  Also, your testing was before we devised the whiffletree and roller edge support, so in some cases performance can actually depend on the altitude the telescope was last used at, or when the mirror was last pushed away from the edge supports!

 

Mike, I understand that differences in scope design will add some amount of variance to the performance of scopes compared with each other. What I do not understand is what empirical evidence you have for saying that mirrors tested in "exactly" the same manner equate to no variability being introduced by the optics and that bench testing negates any differences in a mirror set's performance? Are you suggesting that all of your mirrors have the same conditions for testing, the same testing equipment, the same techniques at time of manufacturer, the same homogeneity qualities, same zonal corrections, same coating thicknesses, etc.? I am not being purposefully argumentative but I don't understand how an optician can say that all of their mirrors should perform similarly and at levels where manufacturing discrepancies are not perceptible to the observer? Especially when we are talking about manufacturing processes and techniques that likely evolve over time.This seems to fly in the face of really knowing what weightings can be assigned to the various components of variability and how this actually translates to the various individual's receptor systems (Steve O'Meara and his legendary eyesight is an example of extreme variability in perceptual abilities). Empirically with a very, very small sample size relatively speaking, I have seen mirrors made by the same manufacturer known for superb mirrors perform slightly differently in the same model of structures. I am not sure how anyone, including an optician, can accurately assign various weightings that would contribute to perceived variability and be able to say categorically that the differences are beyond the threshold of perception?

 

Mike, Hold the presses! In a conversation with a longtime optician this morning, it turns out that the Airy Disk Diameter (um) at a wavelength of 520nm is fully correlated with f/#. If one Googles Edmund Scientific about the limitations on resolution and contrast which are the Airy Disk, Edmund has published some values on the Airy Disk diameter that appear to have an exact correlation of Airy Disk diameter to f/#. In a publication from Edmund on the net, they describe the Airy Disk at f/2=2.54 m and at f/4=5.08um. It appears that the faster the f/ratio of a perfect optic, the Airy Disk will due to some properties of light have an inherently smaller Airy Disk as the f/# decreases. This new piece of data may in part be the reason that I was "chasing my tail" in upsizing the secondary mirror to try and get a smaller Airy Disk in the previously described shootout when in fact, the difference of the two optics you made where one was f/2.75 vs. f/3.55 may have been the most significant factor contributing to the slight variability of the Airy Disk sizes we perceived. Both optics were made before your recent acquisitions of some reportedly very sophisticated interferometers.

 

So, keeping with the thread at hand. Not only did Ed build one of the most complex Newtonians on the planet but his choice of using an optic with an f/ratio=2.75 was a wise move in terms of an optic producing the smallest Airy Disk possible. Given these revelations, I would not want to compare my current f/3.58 28" up against Fast Mike's 28" f/2.75 because at least theoretically, the f/2.75 will show a smaller Airy Disk due to the physics involved. Believe it or not, the findings from several years ago in that fun two-weekend shootout have been bugging me for a long time and I had not come upon what is likely the most important factor until this morning about the correlation between f/# and the size of the Airy Disk. Whew!


Edited by Bob S., 04 August 2017 - 09:29 AM.


#34 opticsguy

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Posted 04 August 2017 - 09:33 AM

Op here.  I would hope we can continue on a positive note in this forum.  This is about wonderful experiences with a wonderful telescope, designed and built by a man with great vision.

The excellent optics are produced by a man dedicated and excited about what he can make with a chunk of glass. 

The scope is the result of many years of education and discovery by a wide variety of people, many mentioned above who are also exploring the current limits of design, creativity and the desire to explore our universe each day and every day. 

 

Nit picking words and challenging people on words they use to communicate ideas is NOT what this particular forum topic is about.  Challenging a person one-on-one should be done one-on-one.

 

Now, back to a very wonderful 24" scope.................................


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#35 Bob S.

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Posted 04 August 2017 - 10:01 AM

Op here.  I would hope we can continue on a positive note in this forum.  This is about wonderful experiences with a wonderful telescope, designed and built by a man with great vision.

The excellent optics are produced by a man dedicated and excited about what he can make with a chunk of glass. 

The scope is the result of many years of education and discovery by a wide variety of people, many mentioned above who are also exploring the current limits of design, creativity and the desire to explore our universe each day and every day. 

 

Nit picking words and challenging people on words they use to communicate ideas is NOT what this particular forum topic is about.  Challenging a person one-on-one should be done one-on-one.

 

Now, back to a very wonderful 24" scope.................................

Opticsguy, I very much appreciate you sharing Ed's story. OTOH, as Mike Lockwood had mentioned when attempting to redirect the thread a few posts ago, he saw this as a review of the 24" f/2.75 mirror he had made which I think is a somewhat different perspective than you are suggesting as the OP.

 

One of the things that is historically important about the development of Newtonians is that all designers/manufacturers stand on the shoulders of those that came before us. I personally do not agree with your concerns about having to share differences of opinion or observations in a one-on-one basis. One of the great advantages I see to these public forums is the sharing of information in a rational and objective manner about how things and why things perform the way they do. As a former scientist, when I see people make statements without trying to assign some objective or clearly articulated subjective experiences, the statements do not then help for myself or others that are interested in pushing the envelope to develop better understandings of the phenomena we are observing. Just my take on the situation and I appreciate your concerns and I would hope that you would understand my perspective. Having owned several fast Lockwood mirrors and currently owning a fast Lockwood mirror set, my post a few posts ago was to share with folks that do not understand how difficult it is to make high-performing fast optics and in this story, mating it with an exceptionally complex structure. I hope that these observations do not violate any sensibilities and are definitely not perceived as picking-nits. You have shared the beginnings of a fascinating story about a fascinating build and I for one greatly appreciate it and hope you perceive my thoughts as a positive note! Bob Schilling


Edited by Bob S., 04 August 2017 - 10:14 AM.

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#36 Mike Lockwood

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Posted 04 August 2017 - 10:23 AM

Are you suggesting that all of your mirrors have the same conditions for testing, the same testing equipment, the same techniques at time of manufacturer, the same homogeneity qualities, same zonal corrections, same coating thicknesses, etc.?

They are all pretty close, within a reasonable tolerance.  That's all I'm going to say.  Yes, there could be slight differences that are barely visible under the best of conditions, but I still think that other things are the cause of any in-focus image variability because those other things have the potential to cause the largest errors.
 

Mike, Hold the presses! In a conversation with a longtime optician this morning, it turns out that the Airy Disk Diameter (um) at a wavelength of 520nm is fully correlated with f/#. If one Googles Edmund Scientific about the limitations on resolution and contrast which are the Airy Disk, Edmund has published some values on the Airy Disk diameter that appear to have an exact correlation of Airy Disk diameter to f/#. In a publication from Edmund on the net, they describe the Airy Disk at f/2=2.54 m and at f/4=5.08um. It appears that the faster the f/ratio of a perfect optic, the Airy Disk will due to some properties of light have an inherently smaller Airy Disk as the f/# decreases.

This actually brings up an important point that is commonly misunderstood, and is relevant here since we are discussing a very fast 24".  I will explain, and then hopefully Ed can take over the thread.

 

Yes, Bob, that is correct, physical Airy disk size at the focal plane (in microns) is dependent on the f/#.  It is not a correlation, it is due to the physical laws of optics and interference that form the disk itself.

However, what you are not taking into account is that the image size at the focal plane varies with focal length.  So, for the 28"s, if you reduce the f/# of one, you do reduce the physical Airy disk size at the focal plane, but you also decrease the focal length and the magnification of the image at the focal plane.  Both the Airy disk and the image itself shrink by the same factor, so the angular size (in arcseconds) of the Airy disk does not change.

 

When you increase the magnification back in to match the other higher f/# scope, this magnifies the image and the Airy disks, and then the views (and the relative size of the Airy disk to the image) are again identical.  This is why telescope resolution is purely dependent on aperture, not f/#.

 

Now back to Ed's 24" f/2.75.....


Edited by Mike Lockwood, 04 August 2017 - 10:25 AM.

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#37 phonehome

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Posted 04 August 2017 - 12:17 PM

Ok, were back...hope the OP doesn't mind my "hijacking" of his thread.

 

Before we move on to the good stuff I would like to mention that the "options" present on the transport unit were brought up to illustrate how helpful something like this can be and maybe stoke other's imagination to think beyond basic mobility.

 

Some pixs to better illustrate before continuing:

Attached Thumbnails

  • Ttansport frontview1.jpg
  • Transport extended.jpg
  • Transport+cover.jpg
  • Transport + cage.jpg
  • Transport rearview.jpg
  • Transport sideview.jpg

Edited by phonehome, 04 August 2017 - 01:59 PM.

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#38 555aaa

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Posted 04 August 2017 - 03:43 PM

I was waiting for that line about cup holders! Outstanding job! The gears are turning in my head....

#39 Mike Lockwood

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Posted 04 August 2017 - 04:00 PM

Cupholders?  I expected a built-in beer cooler or tap, and a bottle opener.  Probably not on the entry-level line, though.  ;)


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#40 Chesterguy1

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Posted 05 August 2017 - 01:12 PM

Cupholders?  I expected a built-in beer cooler or tap, and a bottle opener.  Probably not on the entry-level line, though.  wink.gif

Many years ago I read an article in the NYT where Volvo of America was clamoring for cupholders in their cars saying it was costing sales.  The Swedish engineers--ever safety conscious--replied that drivers shouldn't be drinking (normal beverages) and driving at the same time.lol.gif   Not sure if that logic applies to Ed's beautiful creation.  Of course we can see that Volvo eventually relented as has every other manufacturer in the auto universe since there isn't a new car made without cupholders and hasn't been for probably at least 20 years.  What the Swedish engineers couldn't have realized is how many other even greater distractions have been added to driving!

 

Chesterguy


Edited by Chesterguy1, 05 August 2017 - 01:14 PM.

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#41 Aperturefever

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Posted 06 August 2017 - 12:09 AM

Really looking forward to seeing your pics and words, Ed, as I am cobbling a quick 24-incher together. And particularly keen to hear about your cooling system ... nothing better than a high-end reflector thread!



#42 opticsguy

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Posted 06 August 2017 - 09:00 AM

Hello Aperturefever;  "cobbling a quick 24-incher together"??   Quite sure we would all like to know more. New mirror?  A new thread?   No pics?  Did not happen.  smile.gif lol.gif smile.gif


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#43 phonehome

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Posted 08 August 2017 - 01:59 PM

It's guess it's time to meet Elvira

 

Her BEST assets:

 

65” eyepiece center height at zenith (at minimum lift height)
Go-to/tracking mode
Push-to/tracking & hybrid/tracking operation modes
Zero-power/no track “float” mode
Electronic Alt & Az clutch system with hand sensor
Electric leveling w/15 degree maximum slope accommodation
Electric adjustable viewing height 

Electric load/off-load from transport unit
Electric primary collimation w/speed control
HEPA filtration system w/mirror cool down protection & speed control
Blue-tooth & no cord-wrap USB port
360 degree rotating cage w/mounting ring
USB charging at pedestal platen
5 piece quiver w/adjustable illumination
Auto heaters for Telrad, Laser, eyepiece & secondary
Pedestal or pedestal-less mini-control box operation
etc...

 

And some of her vital stats:

 

Optics: Lockwood primary & secondary: 24”/610mm, FL 66.25”/1683mm, f2.75, 1.7” edge, 6.5” m.a. secondary, L=16.3”, traditional Newtonian design w/0.63”offset, 27% obstruction
Primary & secondary coatings by Zambuto
Whiffletree/edge roller mirror cell, 18 point [Plop] by Aurora Precision (modified)
Spider/secondary holder Super Duty Type 5 by AstroSystems (modified)
Starlight/Paracorr SIPS coma corrector, Aurora Precision filter wheel
Aluminum construction (mostly 6061 alloy), weight 364 lbs. not including transport unit
Electric lift range 7.7”, total lift capacity 6,300 lbs.
SiTech (Sidereal Technology) Servo-I control system
12 volt 180 watt-hour lithium iron phosphate power system
Mirror box dimensions: 27”x27”x5” (sans truss-tube connections & filter assembly)
Rocker box dimensions (sans bearings & Alt shafts): 32”x32”x4.325”
Ground board dimensions: 29.7” diameter x 4” height

Minimum ground board to earth clearance 1.25"
Footplates (3) @ 5.25” diameter w/D-70 rubber pads
Cage dimensions: 29.4” O.D., 26.20” I.D., 15.0” high, weight 38 lbs.
Truss tubes: H.M. carbon fiber 1.25” O.D., connectors by Aurora Precision & Moonlight (combined)
24-channel rotating slip ring, 8-channel traveler, 8-channel cage cable, 25-channel Pedestal

 

Pixs with more to follow:

Attached Thumbnails

  • Elvira Lowered5A.jpg

Edited by phonehome, 08 August 2017 - 05:00 PM.

  • Doug Culbertson, ctcables, Mike Lockwood and 7 others like this

#44 phonehome

phonehome

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Posted 08 August 2017 - 02:04 PM

Maximum elevation height + transport

Attached Thumbnails

  • Elvira Elevated+Xport1.jpg

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#45 phonehome

phonehome

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Posted 08 August 2017 - 02:10 PM

Note the outward angle of truss tubes

Attached Thumbnails

  • Elvira Elevated2.jpg

Edited by phonehome, 08 August 2017 - 02:11 PM.

  • ctcables likes this

#46 phonehome

phonehome

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Posted 08 August 2017 - 02:13 PM

Through the cage

Attached Thumbnails

  • Elvira MB Down.jpg

  • ctcables likes this

#47 phonehome

phonehome

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Posted 08 August 2017 - 02:22 PM

Elvira half-loaded.  Is that ok to say here?

 

Elvira Half Loaded.jpg


Edited by phonehome, 08 August 2017 - 06:12 PM.

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#48 phonehome

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Posted 08 August 2017 - 02:23 PM

Docked clearance

 

Attached Thumbnails

  • Elvira-Transport Fit.jpg

  • ctcables and havasman like this

#49 havasman

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Posted 08 August 2017 - 02:33 PM

She's stunning!



#50 rowdy388

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Posted 08 August 2017 - 03:53 PM

Niced curves too!




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