Equipment Review

By Bill Dellinges (1/03)


Swarovski 8x50 binoculars

Purchased: Eagle Optics, $1104.


Circumstances had recently allowed me to consider buying a high end binocular for stargazing. My needs were for a general use, relatively low power,  portable binocular. I looked at Leica but their eye relief was too short to my liking. Zeiss was out for the same reason and I didn’t care for their looks. The classic Fujinon 7x50 FMT-SX was out because I wanted more than 7x  (plus the 7.1mm exit pupil has been getting bad press lately, the point being the pupils of an aging relic like myself can’t open to 7mm…maybe 5mm (?). I didn’t see a Nikon that fit my needs. Several years ago I had bought a pair of 7x42 Swarovski roof prism binoculars for birding and found them to be superb. Thus I turned an eye to their 8x50 roof prism model. The controversy about porro prism binos being better than roof prisms was a concern, but Alan Adler’s comment on this issue (S&T, Sept. 2002, p.98) laid those concerns to rest. Though tempted by the Fujinon 7x50 due to its reputation and relatively low price (~$500), the “Swar’s” would give 8x, an exit pupil of 6.25mm (aperture/power), and be lighter and smaller. Minutes after unpacking them, I knew I had found my optical nirvana. The huge eye lenses offer 21mm eye relief, enough for me to see the full 7 degree real field with my glasses on. The apparent field (power times real field) is 56 degrees, giving an almost Nagler- like experience. Like the 7x42’s, there are neat depressions under each barrel to accommodate your thumbs. They are a bit heavy at 41 ounces (the Fuji’s are 53oz!), but since you’re not likely to hike with them, that’s not a problem. Like the 7x42’s, the optics are first class. Both pairs give me the impression there is no glass in them-it’s like a magnified image is somehow magically placed in the barrels for you to enjoy. I’m reminded of the phrase some scope owners say about how you need to buy a mount that “gets out of your way” so to enjoy viewing. Well, the Swarovski optics get out of your way too, their lack of aberrations is uncanny. This is not to say stars won’t flare near the edge of the field. Stars are a MOST unforgiving test object. No binocular can keep a star a pinpoint object near its edge-that’s just the nature of the beast because of their short focal ratio. So the only question is how far from the center of the field of view do you begin to see deterioration of stellar images? Most binos can keep a star from flaring out to about half the distance from center to edge. I found the Swar 8x50 could maintain a pinpoint image out to about 2/3 the way-that’s pretty good. (Note the star test is a critical test, terrestrial views are much less demanding). Misc info: close focus: 16.5’, twist down eyecups, nitrogen filled, multi coatings on all air to glass surfaces, water proof, phase corrected, tripod adaptable, made in Austria.


Performance: Titan (mag. 8.4) could be seen. The Hyades can fit in the 7o field. Pleiades glorious. Doubles (tripod mounted): I split Delta Ori (52”, mag 2.2 & 6.9), Zeta Lyr (43.7”, 4.4 & 5.7), Struve 747 (Orion’s Sword) (36”, 4.8 & 5.7), Albireo (34.5”, 3.1 & 5.1). Unable to split: Eta Per (28.4”, 3.8 & 8.4), Struve 745 (Orion’s Sword) (28”, 8 & 9), Trapezium (widest pair, B-D, 19.2”, 6.3& 7.5). I split: Theta Ser (22.4”, 4.6 & 5), 78 Cam (21.6”, 5.3 & 5.8). So it appears they can split doubles down to about 21.6” as long as the components are not dimmer than about mag. 8 or overwhelmed by a bright primary. This list of separations just demonstrates their resolution, their real purpose and best application is, of course, perusing star fields. In this respect-wow. They seem to “gulp” in the stars, the wide field rich in bright sparkling stars against a black background providing a beautiful porthole view to space. These binoculars are top quality and built like a tank. I can’t imagine a finer pair of 8x50 binoculars.