VSI Imaging Products at Work, Helping to Image the Real Universe

SLIDER 2 SKY & TELESCOPE Test Report (July 2002)

"Try not. Do. Or do not. There is no try." - Yoda

The 16" RC Telescope of Keith Quattrocchi, MD, PhD

Located in Lewiston, Maine

A very impressive 16" f/9 Ritchey-Chretien scope by RC Optical Systems on a Bisque Paramount ME equatorial mount. The scope has a 45 arc-second pointing accuracy (yah, I said arc-second) using Bisque's T-Point model software and a 350-point error correction grid. The imaging train consists of an RCOS field flattener and VSI Mega-Port Sidewinder optical manifold with an SBIG ST10-XME CCD camera at the output of the Sidewinder. The scope also has a Takahashi 106 FSQ refractor with SBIG STL11000 piggy-backed on the RC scope. Keith guides with an internal SBIG 237 CCD or an off-axis guider (402 XME). See his Sidewinder comments at our COMMENTS link.You can find more info on this spectacular installation at Keith's web site at www.maineastro.org.

The Backyard Observatory of Dale Mais

Located in Southern California

Dale's installation is anything but typical, and he's doing real science, too. In conjunction with the University of Denver and Dr. Robert Stencel (known as Dr. Bob by the locals), he's monitoring Mira-type long-period variable stars trying to catch any short-lived flare activity. The scope is a 14" Celestron SCT with a piggy-backed 5-inch f/6 Astro-Physics refractor. These two scopes are then mounted on a German equatorial Paramount by Software Bisque. The imaging train (inset above) uses our VP Slider to instantly switch between a Santa Barbara Instruments Group ST-8E CCD camera and filter wheel, to a SBIG spectrograph connected to another ST-8E CCD camera. In addition, there is a spectral calibration lamp, various motorized focusers and a mass of wires dangling from the scope's imaging train. All this is supported by one Slider. Whoa! Could any other similar commercial device even come close to supporting this extreme [over] load? I'll leave this question rhetorical, because you know the answer. You can read more about Dale's equipment and research by referencing the article in Sky & Telescope magazine (May 2003 issue, page 51) or visit his web site.

The Portable Telescope of Scott B. Schneeweis

Located in Pearl City, Hawaii

Scott's Celestron C-14 OTA is mounted on a Losmandy HGM Titan. VSI's Giant 2" Hexagonal Turret, with integrated 2" filter slot adapter, is loaded with 6 Televue Nagler eyepieces including a 31 Nagler (the hand-grenade!). He is using this as a portable assembly. While the total weight of the rig runs approx 240 pounds, everything breaks down into manageable components; the heaviest is the Optical Tube Assembly itself at 45 pounds. The Van Slyke turret, with eyepieces adds 12 pounds and approximately 9 inches of back focus (easily compensated for by the C-14 primary focuser). With the Astro-Zap rigid Dew Shield in place, and the OTA dovetail slid far forward in the saddle, tube counterweighting is not required to offset the addition of the turret.

Additional non-stock items include an after-market extended counterweight bar, AP illuminated 8x50 finder plus Televue Starbeam and Robin Cassady 23 pound stainless steel counterweights. The mount seems to handle the OTA well however future plans include migration to the Paramount ME to accomidate this OTA as well as a larger 18" Classical Cassegrain currently under development by Astrophotographer Richard Crisp.

A Permanent Home Observatory with Full Robotic Control

Located in Nevis, Minnesota

This observatory installation belongs to Rick Johnson. His 12" Meade LX200R is on a Paramount with pointing and imaging robotic control from inside his house via a notebook computer. Rick's imaging train holds a VSI MacroGlide OMEGA 3" focuser installed directly to a VSI Sidewinder Optical Manifold. His imaging camera is an SBIG STL11000, with an SBIG ST10 as a guiding camera. And the STL CCD camera's silver finish matches VSI's glass beaded finish perfectly. Note the 2" Televue eyepiece used for visual observing and/or target acquisition.

Installing a VSI optical manifold has many advantages besides instantly observing [through an eyepiece] what your imaging camera sees, and guiding using its built-in off-axis guider capabilities. You can also visually observe the night sky using the optical manifold as a simple diagonal, without having to disassemble your entire imaging train and rebalance your scope. And when you want to manually [knob] focus using an eyepiece, a simple turn of a knob disengages the Hurst stepper motor from the MacroGlide focuser's gear train.

He uses a mirror on the back of the scope as a safety interlock. When the scope is parked, an infrared eye hits the mirror and returns to the receiver. The roof won't roll unless the circuit is complete. Most of the time, Rick runs his scope entirely from the house and can't even see his observatory.

The scope is 16' above ground level. There's a reinforced concrete pier separate from the observatory structure that carries the scope. It extends into a large base 4 feet underground (see picture at right).

Since the changeover to a VSI imaging train, Rick says his corner imaging resolution has improved considerably. Flex in the Meade "Micro Focuser" was killing one corner of his images because the focuser couldn't hold the STL series camera parallel to the image plane. All VSI products are guaranteed zero flexure under any load, period!

Emmanuel Schalit's 16" RCOS on a Paramount

Located in Paris,France

Emmanuel calls this installation an amateur endeavor. Looks professional to me. The hi-end components include a Paramount German equatorial mount, a 16" RCOS Ritchey scope, a VSI Sidewinder and SBIG STL11000 CCD camera. Just for the record, Mr. Schalit noted that this is not him in the picture below. It is his friend, Thierry. However, Mr. Schalit did have this to day about the Sidewinder. "The Van Slyke Sidewinder (signed by Paul) is an incredible device allowing you to do both off axis guiding (note the SBIG remote guide head in black, above left) and visual work without any change in your imaging train." You can see a slide show about the installation of this equipment and more at his web site.

A 36" f/4.8 Robotic Newtonian

Located at Kingsland Observatory, Ireland

The VSI custom built focuser (see MACHING link for more info on this focuser) has an Apogee AP8p CCD camera attached offering a field of view of 20 minutes x 20 minutes of arc. This scope has been upgraded to operate as a robotic telescope in preparation for a statistical sky survey in collaboration with the Planetary Space Science Research Institute in the UK. The VSI focuser was custom designed with a full 2" internal clear aperture drawtube built-in. Custom machined many years ago, this focuser is very similar to our giant MacroGlide focusers and was upgraded from its original DC servo motor to Robo-Focus control recently. The scope's builder, Eamonn Ansbro is on the hoist at the focusing station.

Steve Bell's Super Astroimaging Newtonian

Located in Elizabeth, Colorado

I don't know much about Steve's super Newtonian but he installed a Sidewinder optical manifold a while back (above left), and recently completed the installation of a new VSI CYCLOID Crayford Disk Rotator (above right). In the near future, he's going to install a VSI MacroGlide OMEGA 3" focuser to replace his existing AstroPhysics rack & pinion focuser. He said that the current AP R&P focuser shifts his image around the chip a bit when focusing, but tolerable for now. The only sure way to achieve zero flexure is to install a robust Crayford focuser, like VSI line of super focusers. He still hasn't sent me a story about his scope, but he is installing a new primary mirror, so after that, I suspect a story will be coming. Although the above left picture shows a Robo-Focus stepper motor installed to drive the rotator, that's been replaced with a DC servo motor because the stepper motor did not rotate the disk fast enough - patience is a virtue! Now he can easily switch between stepper and DC servo motor. He uses it exclusively to remote rotate his entire imaging train in the Z-axis to find adequate guide stars. If you're an astroimager, you know how difficult it can be to locate a useable guide star. Steve is very impressed with the rock-solid, zero-flexure operation of his new VSI CYCLOID rotator.

VSI's Sidewinder optical manifold can install on any scope, even Newts, as you can see. You can create some amazing configurations using its myriad of different output ports, and it even has a special pick-off mirror port with dual-axis mirror control (see ROTATORS, MACROGLIDE FOCUSERS and SIDEWINDER links for details).

Steve has recently installed a VSI 3" MacroGlide focuser on his CYCLOID and, even more recently, installed a rock-solid VSI Spider assembly (see picture below and VSI's SPIDERS link). You can also visit Steve's web site.

Jeff Bennett's Zerotator and MasterGlide Focuser Installation

Located in Ojai, California

Jeff docked a VSI 4.5" ATLAS Zerotator directly to his Meade 12" RCX's 3.25" threaded visual back. Then he installed his VSI 2" MasterGlide focuser onto the output of the manual Zerotator. VSI has dozens of port rings that will adapt our Zerotator, Sidewinder or Targetron (the former all use the same 2.9" proprietary port rings) to any configuration you can concieve. In this instance, Jeff used our SR325 3.25"-16tpi female docking port ring on the input side of the Zerotator and our RR325 3.25"-16tpi male reverse port ring on the output side duplicating the scope's visual back 3.25" threads on the output of the Zerotator. This combination allowed him to "sandwich" the Zerotator between his scope's visual back and his existing VSI focuser. Now he can rotate his entire imaging train, including the focuser, with a single touch. The more you load the Zerotator's radial ball bearings, the more stable your imaging train. The same principle applies when you load the tapered-race roller bearings on a German equatorial mount. See VSI's ROTATORS link for more info about our manual and auto rotators.

The University of Denver's Meyer-Womble Observatory

Located atop Mt. Evans, Colorado at an altitude of 14,148 feet

The Mt. Evans observatory packs a pair of 28.5" reflectors mounted in a unique double ended yoke. DU claims to have the "world's highest operating observatory." The above right inset is the observatory facility that houses the dual telescopes. The structure is designed to handle very high winds. The left inset is a close-up showing VSI's Versa-Port Flipper (now discontinued) inserted in the business end of the left tube assembly.

Clint Lincoln's New Tak that has EXTENDED BACK FOCUS!

Located in Frederick, Maryland

This is Clint Lincoln's NEW Takahashi TOA-130 Ortho-apochromatic scope (130mm lens at 1000mm focal length) that has plenty of back focus to accept a long, extended imaging train, like the one pictured above. Clint even has a VSI micro-fine secondary focuser (MGF1) piggybacked in the imaging train and the scope's [coarse] primary focuser has "in-focus" room to spare. It was designed to offer the imager more than adequate back focus as well as being highly corrected for chromatic aberration. From the sky side, the aftermarket imaging train includes, a new VSI MGF1 focuser, a [1998 vintage] Versa-Port Slider, and a CCD camera. From the Tak's 2.7-inch primary focuser, there is about 10 inches of back focus allowing a CCD camera to be in focus with plenty of other stuff in between. In the pic, the CCD camera is in focus and the primary [Tak] focuser is still racked-out about an inch. Whoa! The Tak tube assembly is mounted on a Celestron CGE w/Nexstar GOTO, and that mount is installed on a STEEL PIER in Clint's backyard.

Finally, a Tak with plenty of back focus! In Japan, guiding is primarily done with attached guide scopes. They do [did] no off-axis guiding so their scope's have [literally] no back focus range. Previously, with the focuser racked all the way in, you barely had enough back focus for a diagonal and eyepiece, let alone an extended imaging train of any kind. This has been their way for decades. No one really knows why. Maybe they think their guide scopes look so cool that they can't part with them? The facts are that guide scopes cause flexure and less than perfect images over long guided exposures - gravity works! You can easily eliminate all flexure and image guiding problems by using an off-axis guider (like VSI's Slider), that guides on exactly what your camera sees, so flexure and other guiding problems are taken out of the equation.

Tom Porter's Televue NP-101 w/piggybacked Epsilon Autofocuser

Located in Peyton, Colorado

The Televue NP-101 is mounted on a rock-solid MI-250 from Larry at Mountain Instruments (see our ASTROLINKS link for MI's web site) with the "goto" being provided by Gemini. A VSI MicroGlide Epsilon focuser (MGF1) is docked to the output of the Televue's focuser using our standard MR224 Docking Adapter coupled to our A2LT 2"-24tpi Threaded Barrel-Nose Adapter (see SLIDERS link, ADAPTERS link). If you wanted more back focus for a longer imaging train installation, you could remove (unscrew) the stock Televue R&P focuser and dock the Epsilon or Omicron model directly to your Televue's 3"-24tpi threaded visual back using another of our standard MR324 docking adapters. The CCD camera at the output of the Epsilon is a SBIG ST10 docked to the Epsilon with our AZP2T Zero-Profile T-Adapter (see SLIDERS link, ADAPTERS link). Anything is possible with the myriad of VSI adapters, converters and port rings that are "off-the-shelf" available. And if we don't stock it, we'll machine a custom adapter for your special installation. Is this super mount overkill? Probably, but such stable accuracy is envied by many. Periodic error is less than 2 arc-seconds (that's seconds, with an S) and the firmware (version 3) has simplified achieving good polar alignment.

You can find more info about Tom's installation at his web site.

Steve Linscott's VSI Bifilar Optical Micrometer with Remote Video Output

Located in Baytown, Texas

Steve's astrometric configuration includes a Celestron C8 on a Losmandy German equatorial mount and a Van Slyke Digital Bifilar Micrometer. The BFM's reticle lines are 10 microns, the digital readout has a resolution of 0.0005", and the 4" diameter position angle indicator has a 0.1 degree vernier scale. Steve machined a sleeve for his video camera so he could switch between the BFM's eyepiece and his video camera (shown installed in the picture above). He views the images on a small monitor, which permits comfortable remote observing in any position, and also eliminates possible parallax problems caused by eye placement at the eyepiece. You can find more info about Steve's installation at his web site.

John Maher's Takahashi Mewlon 210 Installation

An old Monster 3 focuser (now MasterGlide) docked to a Takahashi Mewlon 210. John had a custom ring machined locally to dock the VSI focuser to his Tak, but VSI can also custom machine docking rings for any scope, if we don't already have one in our extensive docking ring inventory. John also said that, "Your focuser is by far light years ahead of anything else I have ever used and a perfect match for the Tak product." Understand, this is the old [now discontinued} Monster focuser. It's replacement, the MasterGlide focuser, is also light-years beyond the old Monster focusers.

Mark Starr's C5 and VSI Imaging Train

Located in Tampa, FL

You don't need a large, fancy, expensive scope to use VSI products. Mark's vintage Celestron C5 was created around 1977. Note the orange tube. He also had the optics refurbished, added a computer, dec and focus motors, and installed an oversize finderscope, not to mention a Slider 2. These modest upgrades re-created a portable scope with very functional and frustration-free astroimaging capabilities. A lot of astro-fun for a reasonable investment.

Ken Crawford's Imaging Train and Rancho Del Sol Observatory

Located in Diamond Springs, CA

The above close-in picture shows Ken's C14 visual back, Slider 2, SBIG 10XE main imaging camera, and his 237a guiding camera at the pick-off mirror. If you want to find out more about his unique, multi-scope observatory, visit his web site.

The Leeward Community College Observatory

Located in Pearl City, Hawaii

This college observatory recently installed a 20" Cassegrain scope, fitted with Byers drives in both axis, from John Stiles of Optical Guidance Systems (OGS). Note the VSI Super Power Focuser (now discontinued) and the VP Slider at the lower right in the picture above. Also note the 12" diameter custom mounting plate above the focuser, which was machined by VSI, according to John's specs. With this custom threaded mounting plate installed, now any standard 3.25"-16tpi Meade/Celestron large format threaded accessory (not just VSI stuff) can be simply and securely screwed onto the visual back of the OGS scope. The observatory's director, Fritz Osell, has purchased many other VSI products for use on this scope and others at his observatory complex, like the VSI remote controlled Dual Filter Wheel (discontinued) and the VP Flipper DFM (which is also discontinued).

February 24, 2007

Re: Thanks for quick response on Cycloid Auto Rotator

Dear Paul,

A couple of months ago, we inquired about your Cycloid Auto Rotator for a project which was on an extremely tight deadline. We are researchers on a plasma machine called the DIII-D Tokamak which is a "star on earth" - a fusion machine that is being developed as an energy source (it replaces the heat source in an electrical plant which is currently using fossil fuels). We want to Thank You for your quick response and your solid product which enabled us to make a tight deadline.

Roughly once a year, the tokamak (a vacuum vessel about the size of a house) is opened for calibrations for a couple of months. We were calibrating an optical instrument that can measure the electrical current profile of the tokamak plasma. This "Motional Stark Effect" (MSE) diagnostic does very precise measurements of polarized light. Just before starting the calibration, a member of our team came up with a new technique that involved spinning an optic (a large "quarter wave plate") in front of a fixed polarizer - this provides both linearly and circularly polarized light to the system. Unfortunately, we had less than a week to put this system together, and so we started looking for a way to quickly make this polarization generator.

I use one of your off-axis guiders in my (personal) astrophotography endeavors. However, I wasn't up to date on the availability of your Cycloid rotators. One of the members of the team found your Cycloid during a search on the web, and he asked me if I knew anything about Van Slyke Instruments! I called you the next day, and you indicated that this wasn't really made to rotate at 60 rpm, but perhaps we could modify the basic design. (This was Wednesday, and I knew you normally only ship on Friday). We called our purchasing people and asked them to rush the order. You assembled a unit for us and shipped it overnight on Friday - using Fedex as opposed to your normal USPS. You even tested the unit to see how fast it would turn with the existing drive mechanism.

When it arrived, we made a simple modification of the drive mechanism and had the unit running at over 60 rpm in short order. A precision stepping motor was used to keep the rotation speed exact. We started calling this "The Wheel of Fortune" and it was used to successfully calibrate our diagnostic. It rotated at a very precise rate with the stepping motor (we took FFT's of the modulated light).

We want to Thank You for your quick response, your "can do" attitude, and for working with us with a "non-standard" request. The basic strength and quality of your product made it possible for us to modify it for our test. I'm enclosing a few pictures of the "Wheel of Fortune."

Sincerely,

Steve Allen, PhD (pictured above)

Lawrence Livermore National Labs At General Atomics

San Diego, CA

Tony Hallas' Astroimaging Train

Located in Foresthill, California

If you don't know who Tony and Daphne Hallas (pictured above right) are, you're new to astronomy, or never browsed an issue of Sky & Telescope or Astronomy magazine. Their pictures have graced the pages, and covers, of these magazines for many years. Their efforts are what we all aspire to achieve. Other accomplished astroimagers pale by comparison. To have the world's foremost astroimager use your equipment is the ultimate compliment. The astroimaging train above left (from left to right) comprise an SBIG USB ST-10E CCD camera for astroimaging, a Versa-Port Slider 2 for target acquisition and guiding, and a SBIG STV for tracking (top center). The scope is a 14.5" f/8 astrographic Classical Cassegrain on a 12" Schaefer mount. To see the best astroimages ever taken from a ground based telescope, visit Tony's web site.

The Vega-Bray Observatory located in Benson, Arizona

The scope is the second largest Maksutov in the United States

Dr. Ed Vega is pictured above next to his 20" f/9.5 Maksutov telescope, which is mounted on a German equatorial mount with a 16" Byers drive. The lower right inset is a close-up of Ed's imaging train featuring a VSI [digital] Super Power Focuser (now discontinued) remotely controlled from an attached warm room.

Dr. Ed Vega passed away on December 16, 2003. He was diagnosed with brain cancer on November of 2001 and has been battling, and [supposedly] winning the battle, as there had been no recurrence. However, due to the fact that he had been receiving chemotherapy during these past two years, his resistance to other illnesses was low. He contracted pneumonia, which his system could not fight. The astronomical community has lost a comrade - an amateur astronomer of great renown. He will be deeply missed by myself and all who knew him, and his observatory at Skywatcher's Inn. - PVS

Chuck Kollar's Copernicus Kintaro Observatory

Located in Pittsburgh, Pennsylvania

This very advanced amateur installation is housed in a 3-meter Observa-DOME. The scope is a Celestron C14 Schmidt-Cassegrain mounted on a restored Cave German equatorial mount retrofitted with Byers drives in both axis. Positioning is completely computer controlled. To eliminate lateral image shift induced by his primary focusing mechanism, Chuck has installed a VSI Analog SPF, and is using a Versa-Port Slider 2 with his ST-7 CCD camera.

An imaging train close-up belonging to world famous astroimager Gregory Terrance

Visit his web pages at http://www.frontiernet.net/~gregoryt

Gregory Terrance's spectacular images have graced the pages of Sky & Telescope and Astromony magazines for many years. Above is Gregory's imaging train attached to his piggybacked refractor. The imaging train consists of a Versa-Port Slider 2 and a very large format CCD camera. Note the dial indicator (upper right) - an ingenius, and simple way to achieve "ballpark" focus every time.

Telescope Creations by Paul B. Van Slyke

NOTE: The following telescope installations and creations are only the biggest & best out of many dozens of telescope projects, since childhood. There will be no more efforts on my part [like the following], for personal reasons, so this is my meager epitaph. Over the years, I have actually enjoyed building telescopes more than observing through them. I can only hope my legacy, such as it is, will help to instill a new generation of Amateur Telescope Makers. Unfortunately, we are becoming a dying breed. - PVS

Black Forest Observatory's 30" Cassegrain Telescope

BFO was the Largest Observatory in Colorado

Black Forest Observatory's 30" Cassegrain is attached to a massive German equatorial mount, driven by a 20" Byers drive. Starting from the skyward side, a custom 2.75" motorized rack & pinion focuser adorns this instrument, which was built many years ago by Paul Van Slyke. Next in line is a custom, large format Versa-Port Flipper, a VSI motorized [dual wheel] 2" filter wheel, and an SBIG ST-6 CCD Camera.

FYI, the scope was sold, dismantled and transported to Gunnison, Colorado in 2002, where it resides [nonfunctional, but reassembled for display] in the Gunnison bank, until funding can be raised to construct a proper observatory for the scope. If you are interested in "The BFO Story," click on picture at left. - PVS

A Unique 10" Fork-Mounted RC Scope

Designed and Built by Paul B. Van Slyke

Project Started: 10-09-95, Completed: 11-10-01

This Ritchey-Cretien scope was built to satisfy my demanding obsession for quasi-perfection. In the beginning, this was to be a scope like no other, and with all the features no other possessed. Although I do know that nothing is perfect, least of all this scope, you must understand that the creative effort itself is the importance of this mission - not the end product. Traveling a path, without knowing the destination, is why we do anything, even though curiosity sometimes "kills the cat" and delays our inevitable journey, either to the creation of a simple telescope, or to a literal journey to the stars themselves (see "Why Space?" link for info on the importance of reaching the stars). The fun is in the striving for that unachievable perfection, maintaining full knowledge that you will never attain that which you truly desire - the quest will be reason enough. A person, who [literally] tries to achieve perfection, never accomplishes anything. Perfection is not possible, so this person [inevitably] never reaches his goals in life. This is sad, because there are a lot of people like this in the world. My philosophy on this debilitating attitude is simple, just do it! What emanates from your effort should be at least satisfactory, and satisfactory is good enough for Vulcans. If people wish to glorify the outcome of your efforts, then so be it. If you are interested in more info on this scope, click on picture at right. - PVS

An Innovative 17.5-Inch Binocular

by Paul B. Van Slyke

Amateur Telescope Making Journal, Issue #1, Fall 1992

Reprinted in the New "The Best of ATMJ" ©2003 (vol. 1 of 2, page 19)

This dual telescope was one of the first really large (700 lbs.) giant binoculars created in the days when light-grasp fever was engulfing the astronomical community. It had two unique features over the other creations of the era. 1) It was all-metal construction, where all the big binos back then were made of wood. Personally, I don't consider telescopes made from wood to be true telescopes. They are dysfunctional and expedient Dobsonians, etc. Is this a snobbish attitude? No, because I grew up in the days before John Dobson's "nature" revolution. Back then, all telescopes were made of metal, period! Yes, I'm a dinosaur, and proud of it! 2) This binocular/telescope could be converted into a multi-mirror telescope by converging the two independent light cones into one. More on this accomplishment in the article. If you are interested in more info on this binocular scope, click on picture at left. - PVS

Four-Speed 17.5-inch Newtonian

Sky & Telescope Magazine, February 1986

Before the creation of Black Forest Observatory's 30" Cassegrain, I designed and built this smaller Newtonian scope on a German equatorial mount, with worm drives in both axis and multiple speed control from tracking to slewing. The truss tube assembly even rotated, at the push of a button, to provide a comfortable viewing angle at the Newtonian focus. This scope was temporarily housed in a small roll-off roof observatory until the 20-foot domed observatory, that would eventually house the 30-inch Cassegrain, could be completed. I sent the pictures and article to S&T and, to my surprise, they published it almost immediately. Click on picture at right to access article. - PVS