I re-entered astronomy by purchasing a 10" LX200 scope on eBay (before I knew about Astromart). This was a good starter system, but as I learned more, I craved more aperture, and also had my eye on the LX200R version - which incoporated "Ritchey-Cretian Like" optics for flatter field, and less coma in the corners. In mid-December 2007, I found a 12" LX200R scope (and accessories) for sale from an astro-imager in Florida. I negotiated the deal and bought the scope just before Christmas. The scope was packed-up and shipped by the seller, and was delivered by Fed Ex the last week of December. My joy was quickly dampened when I opened the box ... take a look at: 12 LX200R DISASTER I have written a fairly complete REVIEW of the 12" LX200R for Cloudynights, which includes my data and perceptios of both the OTA and the LX200 fork mount. Overall, I am quite pleased with the OTA - which I have now de-forked and mounted on a Paramount ME. The LX200 fork mount was incredible for the price, but I bumped up against its limitations in terms of pointing and tracking accuracy, as well as periodic error (which could be corrected from about 25-30 arcseconds to about 5-6 arcseconds - still not good enough for high-level astro-imaging ... unless you're using an adaptive optics accessory, which will correct most of the LX200 errors. The Meade LX200 telescope has been a standard of amateur astronomers for several decades, and has always been my 'dream' scope. They come in 8"-16" versions (this is the nominal diameter of the primary mirror), and the 10", 12" and 14" models are considered to have a reasonable aperture for imaging, but are still relatively portable. I had planned to take the scope to dark remote sites, but even the 12" is quite heavy, and probably not handleable by a single person safely. The LX200 scopes come with the OTA, an 8x50 (i.e., 8 power and 50mm in diameter) finder scope, the fork mount and drive electronics, the hand controller, and the Giant Field Tripod (as well as a 2" diagonal and 26 mm eyepiece). This model includes a GPS receiver, and automatic alignment and leveling capabilities. The "R" in the LX200R was intended to denote that this scope incorporates a new generation optical design, which - although not having classical Ritchey-Chretian mirror curves - is supposed to provide "Ritchey-Chretian like" performance - i.e., flat field and very little coma at the corners of the image. This is increasingly important as CCD chips get larger - or, perhaps I should say "large CCD chips become more affordable for amateurs", as the scope must cover a larger field-of-view (FOV) with minimal distortions and field curvature. Meade got in a bit of trouble over the "R" designation, as the companies that actually make Ritchey-Chretian scopes did not appreciate Meade calling this a Ritchey-Chretian, as it does not use the Ritchey-Chretian mirror curvatures - which are hyperbolic. Hyperbolic mirrors are more difficult (i.e., costly) to grind and polish, and more difficult to test. So, Meade changed the name of this scope to the LX200ACF - with "ACF" denoting "advanced coma-free". Thus they are advertising the resulting performance, without advertising the optical design, or confusing the public with misleading designations. In any case, I have found that the LX200R does have very good optical performance, although probably not on par with the 'real' Ritchey-Chretian scopes, as manufactured by RC Optical Systems and Optical Guidance Systems, among others. |
I finally got the 12" LX200R scope back from Meade, with fully replaced optics in late March 2008. The system I had bought (through Astromart) also included a JMI Wheely Bar, anti-vibration pads, 2" flip-mirror system, dew shield, and several other accessories. I ended-up buying some additional accessories for this scope, as shown in the photo to right, including a Feathertouch Micro focuser (replacement for the LX200 focuser knob), 3D counterweight set (bar and sliding counterweights, which you can see below the scope) - which is needed to balance the scope when the Megrez 90 is riding on top, dew heaters (such as the one around the front of the scope), a Telrad 1x finder, etc. |  |
 | The scope is shown at left mounted on the Meade UltraWedge - which is a more robust version of their wedge (vs. the "Superwedge"). This allows the scope to be equatorially mounted - i.e., with the Right Ascension (RA) axis parallel to the earth's axis. You can see the control handpiece for the scope in a holder to the left of the fork. In this view, the Megrez 90 refractor is mounted in Losmandy guidescope rings on Losmandy dovetail adapters (DAs), riding on a Losmandy dovetail on top of the scope. The coiled cord seen to the left of the scope connects the Meade Zero-Shift Microfocuser to the electronics in the base of the mount, allowing focusing via the handpiece (or via computer). The focuser is called "zero-shift" to differentiate and improve upon the normal SCT focuser (knob that moves the mirror on a tube), which definitely shifts the image around, as the scope is focused. It is basically a Crayford style motorized focuser, but without an absolute position reference (or stepping motors). Therefore, while it is great to use visually with the scope, and it can be used with the MaximDL and other focusing routines, it isn't really capable of working with FocusMax in an unattended robotic set-up. |
Here you can see the corrector lens and secondary support for the 12" LX200R scope. I later replaced the screws on the secondary with "Bob's Knobs", which allow much easier collimation of the scope, without requiring hex wrenches (that can fall into the corrector when it's dark at night and you're trying to reach up to collimate the scope). You can also see - inside the scope - the tube on which the primary mirror rides, when focusing the scope. The edge of the primary mirror can also be seen. This is a 12" scope, with 305mm aperture and an f/10 optical system, resulting in a focal length of 3050mm. Actually, with my current optical train, my working focal length is 3260 mm, which is quite long and makes it a challenge to center objects, focus precisely, and guide well-enough to get round stars.
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 | Here, the scope is set-up for basic imaging, with an SBIG ST-4000XCM CCD camera and AO-8 adaptive optics accessory mounted to the Meade microfocuser. On the left fork is mounted a Kendrick Premier dew heater controller, which provides regulated heating of several dew strips - on the front corrector, on the finder, on the Telrad, and even on eyepieces, if needed. Just to the left of the dew controller, also on the left fork, is tied a 2.5 lb weight that helps keep the drive loaded to the East - i.e., against the direction of motion - in an attempt to reduce backlash and keep an even equatorial drive motion. |
Here, you see the entire system - the Megrez 90 and 12" LX200R scopes on the Meade fork mount, on the Meade UltraWedge, on the Meade Giant Field Tripod, on the JMI Wheely Bar which, in turn, is sitting on Meade anti-vibration pads. On the wheely bar are mounted power supplies, a Celestron PowerTank17 (17 amp-hour battery) and inverter - still thinking about field operation (which never happened). The only wires to the scope are the mains power and USB to connect to the computer. I tried several different approaches to long-distance (100' / 30 m) commnications, including multiple 5m active USB cables, and also USB-to-Ethernet converters that allowed connection via Cat 5 cable. However, I ended-up sitting outside in the cold many nights operating the scope under direct vision. There were always things I had to change or adjust, so I was not anywhere close to remote operation at this stage. |  |
 | Here is a view of the back of the scope. You can see the SBIG camera (with its power, computer, and guider connections, as well as cable to the AO-8); the 3D counterweight (just below the scope); the Feathertouch Micro focuser (gold knob); the finder (left) and Telrad (right); and Megrez 90 riding in guidescope rings on a Losmandy rail at top. The bump on the top of the left fork is the GPS receiver, which operates in conjunction with the Meade electronics to set-up the scope. |
Here is my set-up circa mid- to late-2008. The scope is rolled out on its wheely bar to marks on the driveway. AC power is connected (orange extension cord at middle left), and the USB is connected to my MacBook Pro (running Parallels). I imaged like this for close to a year, before the Dell laptop (mounted on the wheely bar), RoboFocus, and other items allowed me to begin operating the scope remotely - from my office in the house. |  |
 | Here's another view of the scope showing the dew controller, 2.5 lb weight on the East fork, and the Megrez 90 and finder scopes on top. The Meade 12" LX200R (ACF) is a relaively inexpensive scope these days, at a list price of $4,500 including the OTA, mount and electronics, Giant Field Tripod, etc. This means you're paying about $2500 for the OTA and $1500 for the mount, plus about $500 for the tripod. And you can include all of the accessories in the OTA price, so the actual OTA is probably closer to $2000 - new. This compares to (much better) scopes like the RCOS (12.5" with controller for $24K), the Optical Guidance Systems (12.5" for $20K), the Ceravolo (12" astrograph for $19-24K, depending on accessories), or the Planewave (12.5" CDK for $10K). And a "$1500-class" mount is considered quite cheap these days (1/10 the cost of a Paramount ME). Nevertheless, the mount does a creditable job, and is surprisingly robust. I was pleased to be able to change cameras, and work on the scope without the image shifting. The mount carried an incredible load, by the time I was done - about 70 lbs - and still had quite decent pointing and tracking. The pointing was certainly good enough to use with CCDAutoPilot, as that will perform corrective moves. And the tracking is good enough (if you're well polar-aligned) to make at least 5-10 minute exposures. [However, I must admit that I had an AO-8 from the beginning, so really didn't have much experience with unguided exposures.]
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I decided to make the cabling neater, so used some cable wraps (?) to bring the multitude of cables from the scope to the electronics (etc.). However, as nice as this looks, the cables become heavier and stiffer, which sometimes can cause drag on the scope and prevent good guiding. So I later took these back off, opting for functionality rather than aesthetics. At this point, I had added the AstroHub (on the right side of the wheely bar), a dew power supply, a Meade MySky (which can find objects - such as alignment stars, as well as directly driving the scope to whatever is targeted by the MySky), and a RoboFocus (controller seen on left leg of the Giant Field Tripod). The Meade handbox is velcroed to the leg of the GFT. |  |
 | One more view of the "neat" cabling. |
The 12" LX200R is a BIG scope. You can't really get an idea of how big until you see a picture with me next to the scope. The scope itself (OTA, fork mount and electronics) weighs around 70 lbs. So, with the Megrez, Losmandy bars, counterwieghts, CCD camera, etc. the entire system (including the wheely bar and all of the electronics on it) weighed close to 200 lbs. Later, when I added my ball bearing driveway mount, I had to roll the scope out on the wheely bar, and then lift each leg onto the ball bearing - and I can tell you that it felt like much more than 70 lbs (or maybe 70 lbs feels much heavier in the middle of the night!?!?) |  |
 | I finally de-forked the LX200R OTA, sold the fork mount, and mounted the OTA on a Paramount ME in May 2009. In this photo, I have the dew shield on the LX200R, which makes it look like a pretty big scope. You can also see the remote guide head "e-Finder" sticking out from the Versaplate below the dew shield at the front of the scope. |
My current optical train is shown at right. It consists of 1) Optec adapter to 2) Optec TCF-S focuser to 3) another Optec adapter, to 4) Optec Pyxis rotator, to 5) still another Optec adapter, to 6) the SBIG AO-8, to 7) the SBIG ST-4000XCM CCD camera (now, the STL-11000M C1 camera). The working focal length of the scope is 3260 mm, so it's actually operating at about f/10.7. |  |
 | This is perhaps a strange view - taken in the observatory with the scope facing upward towards the dome slit. This is prior to selling the Megrez and replacing it with an FSQ-106EDX III astrograph. |
This is what the 12" LX200R OTA looks like currently - mounted on the Paramount ME on a permanent pier in the observatory. |  |
Meade LX200R LX200ACF telescope Ritchey Chretien astro-imaging astrophotography scope astro-imaging astrophotography deforked Paramount ME observatory