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Meade LX-200 8



Optics

The optics on my scope are good, though comparing them to excellent refractors makes them seem less than perfect. For a Schmidt-Cassegrain telescope, however, they're excellent. You have to remember:

1. SCT's have a large secondary, which lessens contrast and reduces the quality of planetary images. Meade's f/6.3 version has an even larger secondary than most SCTs. For this reason, and because the addition of a focal-reducing lens(such as the one made by Celestron) can reduce the focal ratio to give wide fields(but without increasing the secondary size-as is done on the f/6.3 version), I most wholeheartedly recommend the f/10 version of the scope. Note that if your interests are primarily planetary, you should not buy an SCT. The Schmidt Cassegrain an be above average in every type of viewing, but is truly exceptional in none.

2. Meade markets this scope with a 1-1/4" diagonal and a narrow-field(though excellent) eyepiece. Most buyers opt for more of the same eyepiece type when purchasing additional eyepieces. I recommend highly the purchase of a 2" diagonal for the scope so that 2" wide-field eyepieces can be used. The recent reduction in the price of this scope allows for this without breaking the budget. And Meade makes some excellent ultra-wide angle eyepieces.

Please be aware that I am a very experienced observer, and have owned and lookedthrough scores of different scopes. The optics on this scope are good enough I have only extremely rarely desired better-even on the planets.

So, buy the f/10 and a focal reducer. You get 2 scopes in one that way: you get the Wide field and short focal length for summer Milky Way viewing, and the long focal length for galaxies and Planets.

Mechanicals

Face it, this isn't a $10,000 scope. It sounds like a coffee grinder when it moves to a new object, and you can almost always hear the motors when it's tracking(in a quiet spot). But it finds objects so well I rarely have a problem identifying the object I've selected (the exception is when there are 5-10 galaxies in the center of the field-telling which one is your target often requires an advanced atlas). The high precision software really does bring each object to dead center. Only the professional observatories normally get that level of precision-certainly no other amateur scope currently does!

So, it tracks perfectly, is very stable(a rap on the tube dies out in <1second), finds any object you select the proper coordinates for (more on that later), and lasts for years. My scope is 6+ years old, has been to the field >100 times, and has never needed servicing.

During that period, I've only had to collimate the scope 3 times, and that was only because I was being particularly fussy. Otherwise, I would never have collimated it at all. Definitely a plus over a Newtonian scope.

It's heavy, though. You cannot separate the tube assembly from the mount(though you can separate the assembly from the tripod-which is the industry's best SCT tripod), so the ensemble is fairly heavy to lift. This, plus the increased flexure in the mount for the 10" leads me to recommend the 8" over the 10".

Software

This has problems. It has a huge number of objects that are not truly deep-sky objects: stars. Also, it has a fairly large number of objects in its memory that are beyond the capability of an 8" scope (unless you're an owl on the Moon).The true number of objects in the memory of relevance to the observer is probably around 12000(an estimate). Also, there are other problems:

1. A significant number of objects in the memory have no information available for the object other than position. Meade used too small an internal memory to allow for details about every object.

2. Due to inaccuracies in the NGC, a significant number of the fainter objects are mis-plotted in the database. The scope is dead accurate in locating the plotted position-the problem is the objects aren't there. This isn't Meade's fault per se-the computer databases available many years ago were not corrected per the most recent "cleanups" of those lists. But, they are cleaned up now, so it's time for Meade to come out with a more accurate database.

3. There are 1000's of objects visible to an 8" scope that are not in the database!! Planetary nebulae, nebulae, open and globular star clusters abound that are much brighter than the fainter objects in the database, but are not contained in the memory. Fortunately, the GoTo function allows pointing the telescope to any coordinate you can enter, so you can see those objects. But you will have to find them in a program other than Meade's. I recommend Megastar or Deepsky 2000, both of which have the ability to contol the LX200 with a computer connection cable right from a laptop in the field! I've done this with mine. My only criticism is that the light from a computer screen destroys night vision enough that it makes the faint objects the computer makes findable hard to see. But finding the Tombaugh, Ruprecht, Dolidze, Trumpler, Collinder, Stock, King, etc. clusters by pointing and clicking makes it all worthwhile.

So, the pointing accuracy is nearly perfect. Resist the temptation to synchronize the position of a faint object with the drive position, though. More often than not, I've found the scope is dead-on-the object is not where the database's coordinates say it is. Of course, this only applies to the very faintest objects. Most brighter objects are exactly plotted.

Conclusions

I give the scope a B+. It could be quieter. Its database could be more complete and useful. It should be manufactured with a fixed mirror and a rear-mounted focuser to eliminate image shift( which is negligible in this scope)-- no one uses an 8" scope to watch birds!. But I've observed thousands of objects with it. And I LOVE spending all my time viewing, not ¾ of my time searching. I star-hopped from 1965-1994. I paid my dues, and learned the sky. But would I go back? NEVER! My only regret is that I didn't do this before 1994. I envy the observers who start with a scope like this-they will never know how hard it is to just find some objects. They'll spend their time talking about observations, not how to make a scope more stable; talking about obscure deep-sky objects, not about how little they can find in the night sky.

And it's CHEAPER than it was when I bought it in 1994. Meade has gone mad. Buy one before they recover their senses. You are buying a scope that could keep you busy observing for the rest of your life. Would you see more in a larger scope? Well, yeah, but I've got 8000 observations in my log now, and I've not begun to exhaust the capabilities of this scope in the Northern sky and I don't have any observations in the Southern 1/3 of the sky!

Take it from a user. If you can afford it, BUY IT.
05/22/00

Addendum to my review of the Meade 8" LX200 SCT: (July 11, 2000)

Reading reviews of other GOTO scopes and seeing that high-power views were often compromised by vibrations in the motor drives, I performed an experiment while viewing several close double stars at very high power:303x and 432x. I centered the stars, focused, evaluated the images (allowing for the less than perfect seeing)--please note that I did this test after my scope had been sitting out for 6 hours to allow for thermal problems to dissipate--and switched off the drive. The result: NO DIFFERENCE. The images did not get steadier. No change. Of course, the images drifted very quickly out of the field at those powers, and I did have to align the scope again to get the drive to work, but I was gratified to see that after 6-1/2 years, the drive was still smooth and vibration free.

It'll be interesting to see if the new LX90's drives hold up as well.

Addendum #2 (October 15, 2000)

Collimation:

I found that collimating the scope with the eyepiece used in a "straight-through" fashion resulted in perfect collimation only when the eyepieces were used "straight through". All diagonals differ from the perfect 90 degree angle that would result in perfect star images when they are used. After 7 diagonals, and a constant repetition of having perfect star images become comatic when the diagonal was added, I realized that because this scope is used only in the alt-azimuth mode, the diagonal is never rotated. Therefore, I recollimated with the diagonal in place, giving me the same perfect star images with the Diagonal that I saw without it.

Astute stargazers will note that this results in perfect star images only in the center. With a Nagler eyepiece, the star images at the edge of the field will now be slightly worse than before. Who examines the star images at the edge of an 82 degree field anyway? And the degree to which they are worse is miniscule.

The perfect thing to do is to adjust the angle of the diagonal mirror in its holder so that a perfectly collimated image is the same whether straight through or with the diagonal. This could be a particularly long procedure, however, with no guarantee of success, especially if you're being fussy. My EZ solution results in better planetary images, better focus on globulars and planetaries and utilizes the collimating screws in Exactly the IN-USE configuration of the scope. My star images now are small round dots with a couple diffraction rings surrounding. Before, they were, at best, oval. **Warning** If you rotate the diagonal in use, this technique will not work. Then, you are better with the straight-through collimation.



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