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William Optics Megrez II

Posted by Doug Peterson   05/16/2004 12:00AM

A new best buy? The Orion 80mm ED is the current champ in bargain-priced ($495) high quality optics, but the new Megrez II 80mm ($595) challenges it and falls short in the color correction department, while being superior in just about every other respect. Its nearest competition continues to be the newly-discontinuted TeleVue Pronto 70mm at $775 OTA + $95 tube ring.

Compared to the Orion, the compact scope from William Optics is 9 inches shorter, narrower-tubed, has a superior rotating crayford focuser, beefier mounting block, and just plain looks cooler, with it's retractable dewcap, gold highlights, pebbled white finish. For a mere $55 bucks more the optional package deal gets you a very nice 2" diagonal (already a bargain at the $129 it normally streets), pushing the scope into almost-a-steal territory.

The original Megrez had a subjective color error halo 40-50% of an achromat. The new lens improves on that according to WO. If the new lens has 60% (i.e. 40% less) of the color of the orginal, we are talking about approximatly three times the color correction of an achromat, approaching the Meade ED and other "almost-apos". Nose to nose, it is color-similar to the Ranger/Pronto ED, but with an aperture advantage. There is still a significant but tight violet halo around bright stars, and the TV 76 is still the compact scope to beat.

Mine arrived with the collimation completely wacked, despite the nice fitted foam "back-packaging", and no signs of shipping damage. The good news, unlike the orginal, is that the cell has three collimation screws that--when loosened and tightened in the correct fashion--allow the rear element to be scooted laterally.

(Draw out the dew cap, carefully remove the spring clip just inside, draw back the dewcap completely off the cell. Do not pinch the lens--as you loosen one screw a fraction of a turn, finger-tighten the others.)

The result was a round, well-corrected star test. No sign of astigmatism or flare, the spherical correction was quite good, with the outermost fresnel ring dominating on both sides of focus (5 rings and a 550nm Edmund interference filter used for analysis). A slight brightening of the center of the pattern on the outside of focus may indicate a slight zonal or axial imperfection, but I do not believe this is a significant problem at this price point. Similar contrastiness on both sides of focus indicate no obvious signs of edge roll or roughness.

Cosmetically, the glass is spotless, and all four surfaces are multicoated, another big second-generation improvement. The foam-ring baffles are not as black-hole-like as they could be, but do the job, and allow you to adjust them if you feel the need (mine were placed just right--neither vignetting nor internal tube reflections were apparent). The focuser is very smooth and very tight--flat trails were visible in the plated finish of the drawtube. The anodizing is very nice indeed, and the overall impression is one of a much more expensive scope.

Recommended for bargain hunters.

Click here for more about the William Optics Megrez 80mm II OTA. -Ed.