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Equipment

 

I began in this hobby during the late 1950's with an inexpensive 60mm Tasco refractor. Quickly outgrowing the poor views offered by that scope, I moved up to a 2.4" Unitron Model 124 equatorial refractor thanks to the generous funding provided by my parents. I had that telescope for about 30 years before moving up in aperture to a Meade 10" LX200. Smitten with aperture fever I then upgraded to an orange tube Celestron C14 purchased locally on the used market. Although I knew the night sky pretty well by that time, the idea of a computerized go-to mount intrigued me. Taking the plunge, I plopped down a bundle of cash on an Astro-Physics 1200 GTO German equatorial mount; a decision that I have never regretted a day since the purchase. The optics of the C14 kept me content as a visual observer until 2001, when I decided to embrace digital astro-imaging. Yearning for higher quality and an assortment of image scales, I progressively upgraded my equipment to include some of the fine instruments shown below. Being mainly a mobile amateur astronomer, I've settled on high-end equipment that does allow, although with some effort, a compromise level of portability that suits my needs.

**NEW** A custom-built telescope by Roland Christen of Astro-Physics, Inc., this 12" Maksutov-Cassegrain instrument is sited at the Las Campanas Observatory in Chile. The optic is an f/8 design with a focal length of 2400 mm. The telescope sits atop an AP 1600 GTO mount with absolute encoders, designed for remote operation using DC-3 Dream's ACP observatory control software.

The package includes an FLI imaging train consisting of a Pro-Line 16803 CCD camera, Atlas focuser and CFW-3-10 color filter wheel with 50 mm square Tru-Balance filters.

 

12.5 RC
Pictured here is my 12.5" RCOS Ritchey-Chretién telescope with a piggybacked Takahashi FSQ-106 refractor, all riding atop an Astro-Physics model 1200 GTO equatorial mount. The Ritchey has a native focal ratio of f/9, but can be reduced to f/6.9 with an Astro-Physics 0.67x telecompressor. The exquisite optics, mechanical design and TCC interface make this scope a real pleasure to use. One of the many really great features of this RC is its carbon fiber tube with an extremely low coefficient of expansion. The telescope is not prone to the temperature induced focus changes that plague many other designs; truly a Focus-and-Forget feature as advertised by RC Optical. I've got the optional TCC (Telescope Control Center) interface installed on this scope, which makes "remote" operation from my nearby travel trailer a real plus on cold evenings!
Celestron 14 The Celestron C-14 was my first imaging scope, shown here with a SBIG ST-8XE CCD camera and Van Slyke M4 focuser. This orange tube model is early 1970's vintage and has extremely fine optics for a Schmidt-Cassegrain scope, rivaling larger scopes in side-by-side comparisons. Visually the views through this scope are awesome, with globular clusters, planets and nebulae revealing an incredible wealth of fine detail. The inside of the OTA is lined with Protostar flocking on a removable sleeve to help trap stray light and increase contrast in the final image. Additionally, I've fabricated and attached two handles to the outer circumference of the rear cell to help handling this beast when mounting or dismounting. Although I don't use it for imaging any longer, preferring instead to use the Ritchey-Chretien or Takahashi apochromat refractors, it still provides a great thrill when I observe visually through it. UPDATE: I sold this C-14 OTA in November 2004.
16 LX200 The Meade 16" LX200 SCT pictured here inside its dome at the Mount Wilson Observatory (MWO) in Southern California. Because of my involvement with the Observatory in setting up this instrument, training of operators, and coordinating the associated public outreach effort of the program, I'm fortunate to have access to this telescope for imaging. The telescope was donated to MWO by Meade Instruments Corporation in 2000 and has been the workhorse of many public and private viewing sessions as well as established research programs throughout the years. The telescope is equipped with an Optec IFW filter wheel and TCF-S focuser, SBIG ST-8XE CCD camera and an AO-7 Adaptive Optics system. It sure is nice to have an imaging platform sheltered from the wind and convenient to be running off AC power instead of the heavy batteries needed for most of my portable operations.
The Astro-Physics 160 mm EDF air spaced triplet apochromatic refractor. I was on the 155 EDFS waiting list since August 1999 but missed notification on the last production run of that instrument, so was given an opportunity to continue on the 160 EDF list. I took delivery of this fine telescope on December 19, 2005, making the total wait 6 years and 4 months. This high quality refractor nicely fills in the "focal length" gap between my Takahashi FSQ-106 at 530 mm and the 12.5" Ritchey-Chretien at 2150 mm (reduced to f/6.9). Inspection of the telescope reveals it to be another masterpiece from Astro-Physics. The fit and finish is perfection. Looking down the barrel, one has to be impressed with the numerous baffles precisely machined into both the main tube and the 4" focuser. The focuser mechanism is as smooth as silk yet obviously built to handle a large load. The first images taken with this telescope attest to its exceptional optical quality and have made a believer out of me. Legendary Astro-Physics quality at its finest.

My latest acquisition is the Astro-Physics 175 EDF air spaced triplet apochromatic refractor, shown here atop an AP 1200 GTO mount.  This telescope is the product of years of technological advancements by Roland Christen in the manufacture of fine astronomical optics.  It was so long ago that I don’t exactly recall when I placed my name on the Astro-Physics “180 list”, but I suspect it was at least 15 years or more until this beauty arrived at my front door.  The 175, like my 160 EDF and all other products made by Astro-Physics, is a masterpiece of design and craftsmanship.  At a native f/8 and 1400mm focal length, this telescope has the ability to record exquisite detail in astronomical objects.  A dedicated f/6.1 telecompressor makes for a versatile imaging platform well suited to wide field photography utilizing cameras with 35mm and larger sized CCD chips.


One might not think going from 160 mm to 175 mm would make that much of a difference in size, but that extra 15mm really does.  In side-by-side comparisons the 175 is larger than my 160 by about 10 inches.  It’s a full 16 pounds heavier than the 160, weighing in at 43 pounds stripped down (no mounting rings).  Finally, the 175 has an optical tube 1.5 inches larger in diameter than the 160.  All this makes for an observatory-class instrument best suited to a permanent mounting such as shown here.


Summing it all up far better than I can, in the words of the master himself, Roland Christen, "I am happy to say that this scope performs up to my full expectations. The design is topnotch using the best glasses available polished to a high degree of perfection………  The design is broad spectrum correction, for both visual and CCD imaging. The glass is ultra-clear BK7 crown mated to Ohara FPL53 premium ED glass. The result is magic."


They say good things come in small packages, but I can assure you they come in large packages too.

 

The Astro-Physics Traveler EDF is an oil-spaced apochromatic refractor having a clear aperture of 105 mm, a focal ratio of f/5.8 and a focal length of 610 mm, making highly accurate wide field imaging with large format cameras possible.  This model has the black pebble finish and is from one of the later Traveler production runs.  The optical tube is of aluminum construction with machined baffles running down the interior length of the tube.   Having an overall length of 19” (with the dew shield retracted) and a total weight of only 9 pounds, it’s the perfect travel scope.   My Traveler has been upgraded with the latest 2.7” ID greaseless, rack and pinion focuser with 9:1 Feather Touch Micro.   The robust design of this focuser easily handles heavy camera and filter wheel loads with no deflection of the drawtube.  A dedicated field flattener and SBIG camera adapter allow for wide field imaging with the STL-11000M camera and insure pinpoint stars right to the corners of the frame.

FSQ-106 The Takahashi FSQ-106 quadruplet fluorite apochromatic refractor is simply one of the finest 4" scopes of its class in the world today. Takahashi really pulled out all the stops when they designed and built this telescope. A buttery smooth and rock solid 4" focuser coupled with a precision camera angle adjuster make this scope an absolute joy to use. Seen here with an attached ST-10XME CCD camera, the recorded field of view is a large 1°37' x 1°05' at an image scale of 2.64 arc-seconds per pixel, making this instrument very well suited to capturing large objects like diffuse nebulae. No wonder the guy standing next to it (me) is grinning!
The Takahashi FCT-76 f/6.4 triplet fluorite apochromatic refractor is my wide field imaging telescope. When used with its dedicated focal reducer the focal ratio and length are f/4.5 and 342 mm respectively. Coupled with my ST-10XME CCD camera, that makes for a 2°27' x 1°39' field of view, allowing for a large object like the California Nebula to be imaged in one frame. I've made significant upgrades to my FCT-76 to incorporate a RoboFocus unit into its design. Basically it's a belt drive system to actuate the helical focuser for precise focusing. The RoboFocus unit rides on an adjustable mounting to allow for proper tensioning of the drive belt and setting of camera angle adjustment without losing focus. Yes, life is very good when shooting at a 4.10 arc-second per pixel image scale! UPDATE: I sold this imaging package in March 2006.
The Takahashi FS-60C doublet fluorite apochromatic refractor at f/5.9 and 355mm focal length is my latest addition to the refractor stable. Attaching a FS-78 focal reducer to this telescope reduces its focal ratio and length to f/4.4 and 264 mm respectively. While many other amateur astronomers suffer from "aperture fever", I am cursed by an equally virile yet totally different bug called "field of view mania". Always trying to squeeze out the most field coverage from high-quality telescopes, the FS-60C and FS-78 focal reducer combo was a logical step in my progression to ever smaller instruments with wider fields of view. Coupled with the ST-10XME CCD camera, this fine little telescope covers a whopping 3°15' x 2°10 swath of sky. The present configuration does not include a Takahashi Camera Angle Adjuster (CAA), so positioning is done by rotating the entire OTA in its mounting rings. Eventually I'll probably add the CAA to the imaging train for ease of operation. UPDATE: I sold this imaging package in December 2005.
The Takahashi Epsilon 180 ED is a very fast f/2.8 hyperbolic astrograph superbly matched to capturing wide field images in a short amount of time. It has a native focal length of 500 mm focal length and an effective aperture of 180 mm (7.1 inches). This small scope has an eye-pleasing yellow finish as well as a fine fit and function. The OTA is rather heavy at 22 pounds with an overall beefy construction befitting the Takahashi line of telescopes. The focuser, which houses the refractive ED corrector in its drawtube, also sports a built in camera angle adjuster to allow for just the right framing of target objects and suitable guide star acquisition.
Shown here is my 180mm Nikon EDAF setup, the widest field imaging system I own. Thanks to the efforts of Steve Mandel and his Wide Field Adapter, this telephoto lens can be coupled to my ST-10XME CCD camera to provide a rigid platform from which to image wide swaths of the night sky. Focus is achieved by means of a Robo-Focus motor belt drive system similar to the one used on my Takahashi FCT-76 telescope (see above). Imaging a 4°45' x 3°10' portion of the sky in a single frame with my ST-10XME CCD camera, this arrangement is capable capturing a large emission nebula like IC 1396 or the Andromeda Galaxy without the need to mosaic. I normally use this arrangement piggybacked on either my 12.5" Ritchey-Chretien or Takahashi FSQ-106 refractor. It would look a little silly mounted alone on my AP 1200 GTO mount and I couldn't properly counterweight it in that configuration anyway. UPDATE: I sold this lens assembly in January 2006
A stable Mount and Pier combination is essential for astro-imaging. The AP 1200 GTO German Equatorial mount is as solid a platform for imaging as can be found in the amateur arena and still be considered portable. You can have the best optics but it's all for naught if they are sitting on a poorly made mount. The 1200 GTO mount has very low, smooth periodic error that is easily guided out by conventional means and has the payload capacity to effortlessly handle any of the scopes I own. The mount rides on a 36 " high Advanced Telescope Systems portable pier, providing the kind of rock-solid stability required for long exposure astro-imaging. I was on the AP waiting list about 2 years for this mount, but every night I use it reaffirms my conviction that it was worth every minute of the wait.
The SBIG ST-10XME by Santa Barbara Instrument Group has made acquiring great images a lot easier. The nearly 90% QE at 575 nm wavelength of the Kodak KAF 3200ME imaging chip coupled with the sensitivity of the Texas Instrument TC-237 guiding chip make this camera a dream machine. At an array size of 2184 x 1472 pixels, this 6.8 micron pixel chip is a great match to my telescopes. Compared to the ST-8XE that I previously owned, I can notice a big improvement in performance with this camera and higher quality in my final images. I also use a Mandel Muscle Plate, SBIG AO-7 Adaptive Optics System, CFW-8A Color Filter Wheel, Tru-Balance LRGB Filter Set and a Custom Scientific 3nm Hydrogen Alpha filter. For video imaging of the planets and moon I use a Philips ToUcam PRO II Model 840 webcam. For astronomical applications it's pretty amazing what can be done with this inexpensive little webcam.
**NEW** The SBIG STL-11000M is currently the answer for "Wide Field Imaging Fever". This 35mm format CCD camera coupled with a short focal length optic captures large swathes of the sky in a single frame, thus eliminating the need for the mosaic techniques required on many large objects with smaller sized CCD chips. The dual head design features a Kodak enhanced KAI-11000M imaging chip with a 4008 x 2745 array of 9 x 9 micron pixels and a sensitive Texas Instruments TC-237 guiding chip. The main use for this camera is to capture monochrome H-alpha images of large emission nebula with my Astro Physics and Takahashi refractors. To overcome the relatively low QE of the KAI-11000M chip at 656.3 nm (the H-alpha wavelength), I use a 6nm Astrodon H-alpha filter with a 90% transmittance. By comparison, the 3nm Custom Scientific H-alpha filter I use with my ST-10XME has a peak transmittance of only about 70%.
The Mobile Command Center is my home away from home and a cozy place from which to conduct imaging sessions. It's a 17.5 foot Coachman Ultra-Lite travel trailer equipped with all the comforts of home, like a refrigerator/freezer, microwave, range and oven, air conditioning and heating, CD player, radio, tape player, toilet, shower and room to sleep up to four. In addition, it's rigged for astronomy as well with red interior lights, batteries, battery charger, an inverter for 120VAC power to run my laptop, and a bulkhead fitting on the side through which all of my control cables pass to the scope located outdoors. It's a great way to image in comfort on those cold nights in the mountains or deserts and has served me well since 2002. I also use a portable 1Kw Honda generator as a power source to charge up depleted batteries when imaging at a remote site without electrical service. Pictured here is the trailer at a campsite in Joshua Tree National Park, California.

To make all of the above listed "stuff" work requires Accessories. Some of the accessories I have designed and fabricated to assist in my astronomy efforts include light boxes, battery packs, Robo-Focus brackets and a 12V gang box to name a few. Purchased items include battery chargers, eyepieces, a laptop computer and various software applications for image acquisition and processing.

Pictured at left is a custom battery box I made in 2001 that housed a 105 amp-hour Gel-Cell battery and all of the circuitry, metering and outlets needed for a night out under the stars. Eventually I found this box too cumbersome to transport and went instead with standard plastic battery boxes for easier handling and storage.

To view construction photos showing the installation of my permanent pier please click here or on the photo to the left.

The pier is 316 stainless steel construction and is 14 inch in diameter x 55" high, weighing nearly 200 pounds and sitting on a 9 ton concrete footing. It's housed in a 17-foot diameter steel dome with insulated walls to maintain an optimum inside temperature. The dome itself is a two-story builing, with a finished control room on the lower (ground) floor for "locally remote" operation.

EQUIPMENT FOR SALE