Meade LX90 Telescope

LX90 with Meade Dew Shield and ScopeTronix accessory tray. Photo taken at Montebello Open Space Preserve, Palo Alto, California, August 8, 2003.
I got my Meade LX90 telescope in mid-July 2002. So far I have a Lumicon off-axis guider (including a focal compressor) and T adapters and a JMI electric microfocuser. I also got a Minolta Maxxum 7 camera (with mirror lock) for astrophotography. I doubt the Nikon Coolpix 990 has the chops for anything but moon shots: it just doesn't have the ability to do long exposures without a lot of random noise appearing in the images.

My initial impressions of my LX90 were extremely favorable. I expected to take some lovely pictures with it.

My scope is mounted on an equatorial wedge, which is the only way to get decent astrophotographs unless you get a field derotator. I figured the fewer motors involved in tracking, the better the result will be. This turned out to be the right idea. When the LX90 is in equatorial mode, the scope rotates around the right ascension axis only, negating the field rotation observed when the scope is mounted alt-az.

The camera is a Minolta Maxxum 7, using a 28-300 mm Tamron f3.5-5.6 aspherical zoom lens. The camera can be hooked up to a piggyback 1/4"-20 mount. I did my first piggyback astrophotos with this camera on the 10th of August 2002; they turned out rather well, considering they were absolutely my first film-based astrophotographs. I shot a wide-field view of Cygnus with hypered Fuji 800 film purchased from Lumicon. I have yet to master Lumicon's so-called "Easy Guider", which is neither easy to use nor (as yet) useful for guiding. I haven't seen ANYTHING but blackness through that guider. Maybe I'm just using it wrong.

LX90 with Baader film solar filter attached
I have a Telrad finder on the right side of the optical tube assembly (from the perspective of the scope's user). Even though the LX90 comes with a small finderscope (pictured), the Telrad makes it possible to perform gross telescope alignments much more quickly. It's also useful at star parties: when a visitor wants to know where in the sky that object in the eyepiece is located, you just point to the Telrad and say, "Pretend that's a gunsight. Whatever's circled in red is in the eyepiece." Eureka! It's very easy to understand that idea, and it's great to be able to identify a particular piece of the sky with a particular deep-sky object.

The counterweight system is from Losmandy. Very nice: it moves back and forth along the rail for balancing the declination axis, and the counterweight can be moved along the axis of the center bolt for balancing the right ascension axis. The 2.5 lb weight supplied with the rail kit is sufficient to balance the scope when equipped with the 1.25" star diagonal and the two finders. I recently purchased an Orion Short Tube 80 (focal length: 400 mm, f/5) for use as a widefield piggyback system. I can use a T-adapter to connect the Minolta camera to the ST80, and use the LX90 to manually guide the system during astrophotography.

I also recently purchased an additional five pound weight from Losmandy. Now that I'm using the ST80 and a 2 inch star diagonal and widefield eyepieces, the original 2.5 lb weight supplied with the balancing kit is not quite enough to bring the whole shebang into balance. I got a 5 lb weight from Losmandy recently, and that works fine with the additional equipment attached. I also need a small off-axis weight to compensate for the slight imbalance around the right-ascension axis caused by the OEM finder scope.

LX90 covered with an aluminized Mylar "space blanket" to shield it from the heat at Fremont Peak's southwest parking lot.
Now that I've had the scope for about a year, I have developed a real affection for it. It doesn't have the aperture of the bigger LX200 scopes, but it's very portable. The tracking is extremely good, much better than I was expecting, at lower magnifications. Unless the scope is drift-aligned, a technique which I have not yet mastered, it does drift off target at higher magnifications. It is a very easy scope to set up, even with the equatorial wedge set up, and the Autostar hand controller is very easy to use.

The biggest problem I've had with the scope so far concerned the handset, incidentally. I bought the scope on clearance at Lumicon in Livermore, just before they closed their doors to drop-in visitors, briefly went out ot business, and then started back up in Simi Valley. The scope had been on the show floor and was probably manhandled by kids before it was sold, because it had a short in the curly wire connecting it to the base of the scope. I returned it to Meade for a replacement, only to have exactly the same problem with the replacement handset! I sent that one back to Meade as well, and the third one I've received works just fine. It was insanely frustrating to use the intermittently-functional handset. I would just get the scope aligned and the power to the handset would shut off, requiring me to realign the scope. Argh! Deeply irritating. But once that problem was resolved, I have had no serious problems with the scope.

It has taken a great deal of patience to learn the proper techniques for using this piece of equipment. It's fairly complex. But it has been worth it. On July 26, 2003, I had my best experience using my LX90 to date. I spent the whole night observing Mars, a month before the closest opposition in tens of thousands of years. The seeing was outstanding. The upper atmosphere was almost completely still, affording me the best chance yet to use my modest high-magnification lenses (10.5 and a 5.2 mm Orion Lanthanums). I could easily discern the south polar ice cap, and occasionally the atmosphere would stabilize for a split second and afford me a view of some surface features. I need to collimate the scope and get some better eyepieces, but the image was not too bad, even in comparison to the immense 10" Astrophysics Makutsov scope with Zeiss optics and a binocular viewer owned by the guy I parked next to at Fremont Peak. This is a very nice scope, and there's plenty I can do to improve it. Better lenses, proper collimation, and maybe a good Barlow lens to get even higher magnification will let me get even better planetary views. And there is a LOT I can do with digital photography. Next year I may get a small CCD camera and try my hand at deep-sky object imaging.

LX90 with dew shield and dew removal system at Lake San Antonio, California
Addendum: August 9, 2003: The last couple of weeks have seen some significant additions to my LX90 armamentarium. I now have a ScopeTronix LX-series accessory tray, which is probably the most useful thing I've bought for the scope to date. The accessory tray consists of a quarter-inch thick plate of powdercoated black aluminum that sits between the base of the equatorial wedge and the tripod. (It screws into the six holes on the top of the tripod very securely.) It has a pair of easy-to-see spirit levels set at right angles to one another, which makes leveling the scope much simpler. The most important feature of the tray is the array of holes for 1.25" and 2" eyepieces. The tripod itself has a small eyepiece tray with three holes for 1.25" eyepieces, but this tray (integrated into the tripod leg spreader) is comparatively difficult to get to. Worse, if you have more than four eyepieces, it's necessary to decide which eyepieces to keep near the scope and which to leave in the case on the table, which means you have to get up every time you want to use one of the other eyepieces. And you are out of luck altogether if you're using 2" eyepieces. Now I can just line them up and use them whenever I want! Much less running around and much more observing. The ScopeTronix accessory tray has made me a very happy camper.

I also just got my first (but definitely not my last) Tele Vue eyepieces: a 7mm Nagler type 6, a 13mm Nagler type 6, and a 22mm Panoptic. These eyepieces have a (forgive the phrase) stellar reputation in the amateur astronomy community. I used them on Mars as it nears opposition, and boy howdy, it is one HELL of a view through those babies. I also got a 2.5x PowerMate, also from Tele Vue, which is like a Barlow lens but better. I used it with a number of my cheapie eyepieces to good effect on Mars and the Moon. Although the atmosphere limits the useful magnification of any scope to around 300x to 400x most of the time, I tried the 7mm Nagler with the 2.5x PowerMate on the Moon last night. Yee haa! It was like looking down at the moon's surface from close orbit (albeit with tired and perhaps slightly intoxicated eyes). As they say in Canada, "Beauty, eh?" Tele Vue will be getting a lot more business from me. Eventually I'll replace my whole collection with Tele Vue eyepieces.

The final important accessory was a Kendrick dew removal system, which I power with a 40 amp-hour deep cycle battery I can lug around in the car. It's overkill, but I don't think I'll have any dew problems when it starts to get cooler. So far I haven't had a real reason to use it. Most of my observing sites are high and dry. But that will change as the weather grows damper this fall.

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