Evostar 100ED Doublet APO Refractor

Observing with the Sky-Watcher EvoStar 100ED 100mm Refractor

Turning the telescope to the first quarter Moon, the Apennine Mountains snap into focus revealing a cornucopia of jagged mountain ridges, canyons, and numerous small craters in razor-sharp detail.  Not far removed, reaching skyward the crater wall of Archimedes pops into view in bold relief against the smooth flatlands that transverse the distance between it and the Apennine Mountains.  This is lunar observing at its best – HD style.  The gas giant Jupiter displays its swirling equatorial bands in high-definition with festoons, and tonality within the bands.  The great spot is clearly visible, discreetly contrasted from the surrounding Jovian landscape.  Saturn’s storied surface phenomenon is simply stunning.  Hunt down double stars like Epsilon Lyrae, the “double-double” in Lyra.  A 100mm refractor will provide a crisp well defined image superior to even a larger reflector.  Always a star-party favorite, Alberio located in the tail of Cygnus never fails to please as it is a beautiful double.  Alberio appears like a gold sparkler and its companion looks blue-green.  It is a perfect refractor object.  Compact globular star clusters lend themselves well to a refractor. Located outside our galaxy the globular M2 will probably resolve more stars in a 4″ refractor than a 6″ reflector.  M4, M10 and many other globular cluster can be seen well with a 100mm refractor.  M13, the fantastic globular in Hercules is a stunning sight in a 100mm refractor.  The bright central cores of prominent nebulae can be seen and the brightest stars can be resolved.  This is just the beginning of an incredible journey of exploration possible with a SW ED-APO 100mm refractor.

Virtually Eliminates Residual Chromatic Aberration

The Sky-Watcher ED-APO design assures virtual elimination of residual “false color” (i.e. chromatic aberration) normally present in 2-element achromatic lens designs which utilize standard crown and flint glasses.

Sky-Watcher APO refractors utilize the finest extra-low dispersion (ED) glass available, FPL-53. This results in the best color correction for an ED doublet lens.

Schott Glass Used in Selected Models for Crown Element

Select models of ED-APO refractors will benefit from the inclusion of Schott glass being used for the positive front Crown element in the objective.  Schott is the recognized world leader in glass utilized for precision optical lens systems, including medical instrumentation, and famous-brand camera lenses.  While Schott glass is only used in selected models, all other models utilize top-quality, Grade-A glass from perhaps less famous but, nonetheless, highly respected, high-quality glass manufacturers.

Precision 2″ Crayford-style Focuser is Standard
Optical focus is achieved by means of a mechanically ultra-smooth, backlash-free, precision 2″ Crayford-style focuser-assembly with 1.25 adaptor.  This focuser operates at 2 speeds for fine and ultra-fine focusing adjustments.

• Evostar 100ED Doublet Refractor witgh 2-speed backlash-free 2” Crayford-style focuser
• Aluminum Hard Case, foam-lined.
• Right-angle 8x50mm viewfinder with bracket;
• 2” dielectric diagonal with 1.25" adapter
• Two 1.25” LE (Long Eye relief) eyepieces (20mm and 5mm);
• Tube rings and Vizen dovetail.