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First Light Report: 20" f/3 Spica Eyes/Lockwood Dobsonian

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#1 Mike Wiles

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Posted 25 July 2019 - 05:24 PM

Eighteen years ago I suffered an acute attack of aperture fever after viewing M51 through a 17.5" Discovery Telescope.  There was one thing I didn't like about the experience - climbing the ladder.  So I bought the largest scope I could that kept my feet on the ground - a 15" Obsession Classic.  That scope has served me well for all of the intervening years since and I've enjoyed hundreds of hours of excellent observing with it and it has done a wonderful job of keeping my aperture fever in remission.  Returning from a dark sky trip in November of 2017, the symptoms of aperture fever overpowered me again, but I still wasn't crazy about hauling a ladder everywhere with me and climbing up and down it dozens of times each night.  I wondered if it was possible to get a larger aperture scope that would provide enough benefit to justify the cost and still be able to keep my feet on the ground.  I began to talk with opticians and scope builders about my "ultimate telescope" with a basic list of requirements.

  • Largest possible aperture without a ladder or step stool of any kind. 
  • Portable - Heaviest component less than 70 pounds
  • Compact - Needs to fit into the back seat area of my GMC truck
  • Tracking will be provided via an Equatorial Platform - no Servo Cat, or Go To system

The Optics
After several conversations with Mike Lockwood about the goals for this telescope and the fact that I'm not the tallest person in the world, I placed a deposit with Lockwood Custom Optics to begin the production of a 20" f/3.0 primary mirror and matched 4.8" secondary mirror. With an equatorial platform taking up about 6" of the eyepiece height, the focal ratio would need to be short in order to keep me off of a ladder or stool while observing.  At just 1.25" thick, the mirror set also saves on the weight of the scope - important for loading/unloading without wheelbarrow handles.  While Mike told me that it could take 6 to 9 months to complete the optics, I got a message from him just 3 months later saying that they were complete - well ahead of schedule.
The Structure
For the selection of the structure, experience taught me that I needed to select a builder with significant experience building large aperture telescopes at f/3.0 and faster.  The list of builders who have this sort of experience is very short indeed - especially when limiting my search to builders in the United States.  After discussing with three builders, I selected a Spica Eyes structure built by Tom Osypowski of Equatorial Platforms.  Detailed information regarding his structures is hard to come by.  I learned when I picked up the telescope that mine was number 39 - so that explains the lack of a lot of information or coverage.  There just aren't many of these scopes out there.  They're truly handcrafted, one at a time.  I was a previous customer of Tom's - he built the Equatorial Platform that I use.  I have been so pleased with the platform's quality that I had an extremely high level of confidence in the structure that he would build.  I contacted Tom on February 1st and received notification that the structure was complete on May 19.  Build time was 3.5 months from the initial contact.  My current client in California is only about a 2.5 hour drive from Tom's shop so I made arrangements to drive my vehicle up and pick up the telescope over Memorial Day weekend.  I was in love with the scope at first sight.  Four days after driving from northern California to Phoenix, I was headed to the magnitude 7+ skies of Portal, Arizona for first light.  The weather cooperated as perfectly as I could ask.  Here are my thoughts and experiences thus far. Constructed entirely of aluminum, the structure is the most solidly built and rigid dob I've ever laid eyes upon.  
The full setup
Laid out on the floor at home prior to packing up, there are four main parts to the setup.  The telescope is stout - 189 lbs (85 kg) total weight, but it's distributed relatively well between the parts.  The heaviest piece is the mirror box of course, at 73 lbs (33 kg) which is slightly over the design spec.  The attached, heavy duty handle makes it easy to move the mirror box about though. Not pictured are the removable 30" altitude bearings.   Note the mirror cover locks in place to protect the optics.  There's a matching mirror box cover for the back side that slides in place and keeps dust out when the telescope isn't in use.  
Interesting features:
Assembled in the house, and placed on the EQ platform, the telescope has an eyepiece height at the zenith of just 63.5" (161 cm) - perfect for me.  
The telescope makes liberal use of connecting hardware from Aurora Precision - and it's insane how well machined the pieces are.  The handscrews and truss connectors to the mirror box are machined to fit tightly together in the same orientation every time.  
The upper truss connections are even more impressive to me.  With two "registration" pins on each of the four upper connections, the UTA literally snaps into place on the truss poles. Even before tightening the knobs, the whole structure is quite rigid.  Once tightened, the entire telescope feels as though it's been machined out of a single block of aluminum - incredibly rigid.  
The mirror cell is also from Aurora Precision and is best described with the phrase "industrial art".  It's well crafted and heavily constructed.  I suspect that the mirror cell actually weighs more than the 1.25" thick optics that it supports.  Only two collimation knobs are used to achieve alignment, as the point nearest the ground is bolted directly to the mirror box and has the ability to pivot based on the movement of the two collimation knobs mounted at the extreme upper corners.  It is a brilliant solution and so easy to use.  The whiffle trees are substantial and move easily, supporting the mirror perfectly.  Finally, there are two nylon screws near the top of the mirror box that are used to secure the mirror in the cell during transport.  
A single 120 mm fan pulls air away from the mirror and is operated with a variable speed potentiometer and on/off switch.  The fan is so well isolated that no vibration is detected at 375x magnification.  A 12v battery built into the bottom corner of the mirror box supplied power for all 4 nights out.  Notice the batter charging port mounted in the mirror box just below the handle.  This port is wired to also supply 12v power to other accessories, though I've not used it for anything yet.    
At the business end of the telescope, an Astrosystems Super Duty II spider and secondary holder keep the large 4.8" secondary in place without issue.  I was happy to see the hub at the center is welded to the spider vanes to inhibit the tendency to twist under the weight of the secondary.  The upper cages is made of aluminum as well, and provides a mounting location for the Telrad, 60mm Stellarvue finder and Feathertouch SIPS focuser.  

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#2 Mike Wiles

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Posted 25 July 2019 - 05:25 PM

Hitting the Road
With my truck being relegated to basically just a camping vehicle these days, I removed the rear seats some time ago to provide more room for gear and telescopes.  The truck camper rides in the bed and provides me a place to live far from civilization for long astronomy outings.  As originally spec'd, the entire telescope - including EQ platform - fits easily into the back floorboard of the truck.  
After an easy four hour ride, I setup camp and prepared for a long weekend of observing with what was promising to be a perfect dark sky forecast. I took my time setting up the scope and answering a ton of questions from my eager observing partners.  Eventually, it was all complete and we waited for darkness and first light.  

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#3 Mike Wiles

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Posted 25 July 2019 - 05:25 PM

First Light Report
Finally, the time had come for first light.  When I put the Glatter laser collimator into the focuser and turned it on to begin aligning the optics, I was stunned to see that the laser beam was hitting the primary mirror inside the circle in the middle of the hotspot.  Despite being driven over 1000 miles and loaded/unloaded twice, the tolerances are tight enough on the telescope. I've setup the telescope four different times since - and the initial laser position on the mirror has been inside the 1/4" (6 mm) hole at the center of the HotSpot every time.  Collimation required less than 1/16 of revolution of any of the knobs on either the secondary or primary mirrors.  I pointed the telescope at the horizon and the zenith.  I moved quickly in altitude and azimuth, and slid the EQ platform through it's entire range of motion twice.  Collimation didn't shift.  At all.  
Once the sun dove behind the hills just to the west of the observing site, I uncovered the optics and started the fan in earnest to get the optics cooled to ambient as quickly as possible.  I carry a 10" rechargeable fan that I used to push air at the front side of the primary mirror, and allowed the built in fan to pull air across the back.  The mirror box is only about 8" deep in total, so air is able to flow easily around the optics and through the structure to help with temperature changes and cooling. Once full darkness had descended up on the observing site, I removed the front fan, rechecked collimation and got to the business of deep sky observing with the new telescope.  I left the rear fan running at full speed, where it's just audible as a background noise.  Later I turned this down some just to quiet the fan in the silent nighttime desert. Temperatures dropped 23º F (12º C) over the next 2 hours. The thin optics and open structure of the observing rig did a wonderful job of keeping up with the change.  
When I first began talking with Mike Lockwood about commissioning a fast, thin mirror he told me that I'd likely never seen what a cooled telescope could really do being that my main observing machine has been a 15" full thickness OMI mirror in a wooden Obsession structure.  I love that telescope, but I learned on this weekend what Mike was talking about.  Conditions that had been blamed for years on poor seeing were not present on this night, even though we all agreed that the seeing wasn't any better or worse than a typical night at this location.  I spent nearly all of my time over the next few nights observing comfortably with much higher magnifications than I'd ever been able to use previously. 
NGC 5139 - Even though it culminates at just 11º above our southern horizon, Omega Centauri was on the meridian at the end of astronomical twilight, so the three of us agreed that it was the obvious choice for the first target.  We're all familiar with the views of this object from this site with instruments of all sizes from a 63mm Zeiss refractor to a 20" f/5 Obsession.  At this low elevation there were some obvious atmospheric artifacts being induced in the image - but we all agreed that this was the finest view we'd had of this granddaddy of globulars.  With a 21mm Ethos I immediately noticed a couple of things.  1 - The telescope maintained perfect balance though it was pointed 10º above the horizon.  When I removed the eyepiece to switch to a lighter one, the telescope didn't budge.  I'm no designer, but I attribute this to the use of the 30" altitude bearings and perfectly balanced design.  2 - I was looking at Omega Centauri with 20" of aperture and a 1.2º true field of view.  The cluster was lost in the middle of a field with all kinds of black space around it. With all that aperture focusing all that globular into the smaller image scale of this wide field, the cluster was astonishingly bright, even by it's elevated standards.  I hadn't changed eyepieces or objects yet, and I already knew.....this was going to be a fun telescope.  At 175x in a 10mm Ethos, the cluster is huge, extending nearly to the edges of the field.  What I noticed most was the stars being impossibly tight pinpoints, with black space around them.  The contrast between the globular's stars and the background sky is the most notable thing from the observation.  
NGC 5128 - This beauty in Centaurus is so close by that you can't *not* look at it.  Again, the contrast was the most noticeable thing about the observation.  With the 10mm Ethos, the dust lane is sharp and well defined across the face of the galaxy and appears nearly bi-sected with a brighter middle - like looking at the great rift from millions of light years away.  
I wiled away a few hours working through the Virgo cluster high in the west, spent some time counting galaxies in the Coma cluster and then happened upon what has been the most memorable view through this telescope yet.  
M83 - Again, it was the contrast.  An absolute pinpoint of a nucleus with two sharply defined bars extending away for a few arc minutes and then turning sharply to form those beautiful, elegant spiral arms.  What struck me most though was the dark lanes between the arms.  As I continued observing, differences in darkness began to appear in the dark lanes, as well as brighter spots in the spiral arms (HII, OB assocations?).  I didn't concern myself too much, I just enjoyed the view.  This telescope rocketed this galaxy to a high place on my favorite objects list.  
M57 - I put the telescope on this old standby and basically went camping at the eyepiece.  With an 8mm Ethos, the central star was just there.  It didn't jump out at you....but it was there and required no effort beyond basic averted vision to see it clearly.  I noted galaxy IC 1296 nearby and that it too was pretty easily seen.  This was where I pushed the magnification.  With a 3.7mm Ethos, the telescope is operating at 475x magnification.  In moments where the seeing settled and the air was steady, the optics weren't even breaking a sweat.  I was able to observe 4 stars seemingly involved with the nebulosity and the central star was a direct vision object at this magnification.  The interior surfaces of the nebula were clearly mottled and uneven and the entire nebula appeard electric green in the eyepiece.  
Veil Nebula - Always a favorite, our small group spent a solid hour cruising the wisps of this supernova remnant with the telescope.  With an 8mm Ethos and an O-III filter, the nebulosity glows as if backlit by some artificial LED source in the eyepiece.  I traced the entire outline of the nebula noting how the brighter wisps faded into thinner and fainter ones as I followed until they just seemed to disappear.  There's a patchwork background of nebulosity that I hadn't noticed before with my 15" scope.  
Great friend and fellow observer Alan Strauss told me I needed to remain still while observing M101.  Uhhhhh....okay!  That won't be hard.  I could sit here all night.  
...and then came the planets.  I have listened to Mike Lockwood bang the drum about planetary observing with big aperture mirrors for quite awhile now.  Like I told him afterward, consider me one of the converted.  Jupiter at any magnification was an absolute razor blade of sharpness.  Where I was used to seeing equatorial bands, I was now greeted with a swirling mess of sharply defined festoons and bands within bands.  Viewing Jupiter this night was the best views I've had that I can ever remember.  My friend Alan commented a few weeks later that the thing that stood out most to him was how sharp the planetary views were through this 20" scope - he wasn't expecting it to perform the way that it did.  I concur.  
Just a couple of weeks ago, I set the telescope up again in my light polluted Phoenix backyard to give a quick view of the moon and Jupiter to my lady.  I've not been much of a lunar observer since I was a kid, but she is in love with the moon....so, it was time to show her the moon through the new telescope.  She's not an astronomer by any means....and she'll be the first to tell you that she doesn't have those aspirations.  I was stupefied when I looked in the eyepiece.  Stop me if you've heard this before - the contrast is unbelievable  - and not just the inky blackness of the crater shadows and brightness of sunlit portions of the lunar surface.  The subtle variations in illumination in the mare and even light differences in color were obvious and a pleasure to behold.  What was supposed to be a quick 20 minute show of the moon and Jupiter turned in to a 2.5 hour session together.  We spent the longest time comparing notes and pointing out features and seeing the smallest details.  The experience has converted me into someone who's ready to look at the moon again.  I look forward to the intersection of my travel schedule with a break in the Arizona monsoon and a favorable location of the moon so I can repeat the experience.  
I wanted big aperture with no ladder and absolutely no compromises on the optical and structural quality of the telescope.  It came with an uncompromising price tag too - but I couldn't be happier with the combination of the Lockwood optics and Osypowski structure & platform.  Mike Lockwood's reputation for ridiculously fast, sharp optics is well deserved and I'd even dare say still underappreciated.  I selected Mike as my optician for a couple of reasons.  1 - He was great to talk too and has been a great resource for all astronomy/telescope related questions since first talking with him back in December 2017.  2 - A couple of extremely experienced observers that I respect greatly both said the same thing - that the best view that they'd ever had through a telescope had Lockwood optics.  I can now say I wholeheartedly agree with their assessment. 
The Spica Eyes structure built by Tom Osypowski is as nearly perfect as I think it's possible to build at this point.  It is substantial, stiff and rigid.  It feels like it's been built for the apocalypse when you put your hands on it.  I chose Tom because of my experience with his EQ platforms and the knowledge that he's built several telescopes that were both larger *and* faster than this project - so I was confident i would get a telescope that matched my excitement for the EQ platform.  I haven't been disappointed.  Twice now I've done business with Tom.  Both transactions rank as the smoothest, most pleasant money I've spent in this pursuit in my lifetime.  I'm proud to be able to say I own one of his telescopes.  
Is the telescope truly perfect?  No.  I have two minor quibbles.

  • There is some stiction in the azimuth axis.  It's not paralyzing, but it is there.  I got after it when I got back home with some car wax and a buffing cloth which has improved it.  Part of this issue is comparing it to the buttery smooth goodness that is the motion of an Obsession.  I've been spoiled by 18 years of use with my 15" Classic.  
  • The light shroud fits really, really tight.  Getting it pulled down over the structure is a bit of a process.  By process, I mean it takes a couple of minutes.  Once it's in place - it stays in place and does a wonderful job of blocking stray light but still allowing airflow through it.  So I'll count my blessings that these are my issues with the telescope.

I realize it's been long winded, but there's little information out there about Spica Eyes scopes.  In fact, there's really not much beyond a different CN thread that was posted a few years ago about a 24" scope Tom built.  I submit this review and future experiences and observing reports as part of that body of knowledge.  Tom Osypowski tends to fly under the radar when discussing premium telescope builders, but his handiwork is among the absolute best out there.  He and Mike Lockwood have earned every bit of credit that they get for their skills and contributions to our hobby. 
A great shot of the observing site in Portal, Arizona, the 20" f/3 telescope described here, and the truck/camper that gives me shelter whilst far from civilization for long periods of time.  The light domes are greatly exaggerated in this long exposure.  The one just to the left of the truck is from Lordsburg, NM - 40 miles (64 km) away.  The light dome to the right is from El Paso, TX - 160 miles (255 km) away.


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#4 herschelobjects



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Posted 25 July 2019 - 05:56 PM

Thanks for a great report on an awesome telescope. These instruments are built like battleships. I acquired my SpicaEyes scope (built in 2012) second hand and got it at an incredible, bargain-basement price (which I will never reveal). Mine is a 22" F/3.3 with Kennedy optics. It is also the Slipstream version, featuring Dan Gray’s impressive Si-Tech drive system, mated to Argo-Navis. As far as I know, it is the only SpicaEyes Slipstream telescope in Canada (someone correct me, please, if I am wrong about that). Now that you’ve got this thread going, maybe other SpicaEyes owners could post pictures here of their scopes. Here’s mine (I top out at about 6-foot tall BTW)...



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#5 starzonesteve


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Posted 25 July 2019 - 06:47 PM

Great write up, Mike. Glad to hear you got yourself a scope you can really love. Hope it brings you many years of joy.



#6 Dougeo


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Posted 25 July 2019 - 08:33 PM

Beautiful scope Mike, congratulations! Those dark skies of Portal Look amazing! Enjoy it!


#7 a__l


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Posted 26 July 2019 - 12:32 AM

What is the weight of mirror box + altitude bearings?
How was it easy for you to install with only two hands on a rocker?


Is the battery inside the box used as a counterweight for balance?

I once read information about the dangers of gas emitted when charging a battery for a mirror coating.

It seems to me incompatible alongside these two things. Near each other. Am i wrong?

Edited by a__l, 26 July 2019 - 12:46 AM.

#8 Mike Lockwood

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Posted 26 July 2019 - 11:55 AM

Great report, Mike, thanks for posting and for your kind words.


It was fortunate that I already had a 20" f/3.0 ready for figuring, and fortunate again that I had a gap in my schedule that allowed me to finish it early.  You were lucky, that doesn't usually happen.


It is always rewarding and fulfilling to see someone go through the process and get to the point that they understand how to get the most out of their optics by utilizing cooling, good collimation, and a good structure.  That is always my ultimate goal when I make optics for someone - to give them good optics and to also give them the knowledge to make the most of them.  (Comparing with your 15" will be an eye-opener when it comes to the effect of mirror cooling.)


I will note that this is a 1.25"-thick Pyrex mirror.  Though not easy to fabricate, this is a good balance between cooling quickly and being able to support the mirror properly.  As mirrors get thinner than this aspect ratio (16:1), the sensitivity to mirror support during fabrication becomes very high, and the difficulty goes up greatly.  Good, modern interferometry shows this.  Though it is implied in another thread right now, one can't just keep making mirrors thinner and maintain optical standards because the complexities go up exponentially for fabrication and for mounting in the telescope.


As I always say, don't be afraid to push up the power/magnification, and enjoy your telescope.  I hope to see you at Okie-Tex some year.

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#9 Starman1



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Posted 26 July 2019 - 02:29 PM

It's interesting, I have found, how much the seeing at my site improved when I went from a 2-3/16" thick mirror with 1 fan to a 1.25" thick mirror with 3 fans in the same diameter.

I concur with both Mikes--a lot of what goes for poor optics these days, and/or poor seeing, is merely inadequate cooling.

1.25" on a 20" mirror?  Noice!

#10 Mike Wiles

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Posted 26 July 2019 - 02:55 PM

What is the weight of mirror box + altitude bearings?
How was it easy for you to install with only two hands on a rocker?

The mirror box is 73 pounds (33 kg), a little heavier than I had hoped when I commissioned the scope.  It hasn't been a problem though, as I was targeting 70 pounds or less.  It is built like a tank.  The heavy duty handle attached to the skyward side of the mirror box makes quick work of loading and unloading the mirror box.  When the mirror box and bearings are dead lifted by this handle, the whole thing lifts in a way that keeps the mirror leaning back into it's cell while it's being installed onto the rocker box.  I then just slide the bearing over the rear teflon pads on the rocker box and the entire thing slides into place.  

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#11 Kunama


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Posted 26 July 2019 - 08:30 PM

That is a beautiful scope Mike.  Love the design !!!  Great First Light Report, I hope the scope gives you years of happy stargazing.


In fact I liked the design so much I contacted Tom O. and asked him if he would mind me cloning the scope here in Australia.

Tom O. very kindly encouraged me to go ahead and build my scope based on his design while adding personal touches to mine.....


I think you can see some similarities:

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Edited by Kunama, 26 July 2019 - 08:31 PM.

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#12 nirvanix



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Posted 27 July 2019 - 03:09 AM

Mr Wiles, you obviously haven't been listening to the right folks at CN. You need a 6" f/10 with a maximum CO of 19% to "properly" view the planets. Kidding of course, and glad you're able to put another nail in that coffin.


Great report. You've got the dream scope of many, so we'll live vicariously through your future observing reports. grin.gif

Edited by nirvanix, 27 July 2019 - 04:11 AM.

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#13 tommm



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Posted 28 July 2019 - 09:36 AM

Very well built scope with a lot of attention to details that matter. And very thorough, informative report!  Thanks!

#14 Saturnalia



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Posted 11 August 2019 - 03:30 PM

A very enjoyable report and something to aim for.


I love big Dobs grin.gif

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#15 Rmorales6


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Posted 10 November 2020 - 09:20 AM

A 20" f/3 is my dream scope. It's awesome to read a review like yours. I'm many years away from owning one but won't stop dreaming!

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