Swift Ultra Lite 8x42 Roof Prism
Wayne Mones, December, 2005

I began my birding career with a pair of WWII Navy binoculars that I bought in a surplus store in downtown Manhattan.  They had independently focusing eyepieces and must have weighed 3 or 4 pounds.  The focus was so slow that I was forced to concentrate on things that didn’t move much, so I really learned to identify waterfowl and wading birds.  I never really believed that anyone could reliably identify anything that moved as fast as a warbler.

 The world changed for me in the mid 1960s when I finally bought a pair of good center-focusing poro prism binoculars.  The experience was like being admitted to birding paradise after years of soul-cleansing in purgatory.  When, in the late 1970s, I entered the big leagues with a pair a top roof prism bins, I felt like I had been duped.  Phase correction was still several years away, and my expensive new roofs were less satisfying than I had anticipated.  The new roofs were certainly sharper, and the physical dimensions were more pleasing than my poros, but the image was not as bright, and the contrast was not as crisp as the image I saw through my poros.  In short, I didn’t feel like the difference was worth the additional cost. 

Today’s top binoculars from Zeiss, Leica, Nikon, and Swarovski are truly incredible instruments.  People who are not ready to go into debt for a pair of binoculars owe a debt of gratitude to these industry leaders because the advances they have pioneered have trickled down (perhaps in diluted form) to the lower price ranges.  For many users, mid-priced bins are still the best value.  There are several mid-priced binoculars currently on the market which cause one to seriously question the need to spend $1,500 or more for an alpha binocular.  In fact, several elite birder friends (one of whom is the former head of a major national birding organization) tell me that they will never again spend more than $250 for binoculars. 

The Swift Optical Company has been in the business of pushing the limits of what is possible in the lower and mid price ranges for almost a century.  The new Ultra Lites continue the company’s tradition of offering great products at modest cost. 

Comfort, Focus, and Handling:

The first thing you will notice about the new Ultra Lite is its appearance  The rubber armor consists of a soft base layer covered by a hard rubber exterior layer.  The two layers are different colors which give the binoculars a very distinctive look.  I tested a pair with black exterior and blue interior armor, but they are available in other color combinations.  To my eyes they are very hip-looking, but beauty, as they say, is in the eye of the beholder.  More important than the appearance is that the binoculars are among the most comfortable to hold and that the two layers of armor should make them more durable.

The front-to-rear balance is near perfect, and the focus wheel is large and well placed.  The focus wheel responds to a very light touch and rotates 1 1/2 turns from infinity to closest focus, which means that they focus fast enough to ensure that you won’t miss any birds, without being too “nervous.”  (Binoculars that focus too quickly can be just as irritating as those which focus too slowly.)  Generally, I find that 1 to 1 ˝ turns is about right.  People with small hands will especially love these binoculars.

 Weighing in at 22 ounces, the Ultra Lites are easy to carry.  The strap lugs are metal buttons which fit into keyhole fittings on the strap.  It is a very neat arrangement, which works well and did not interfere with my hands, but I would like to see it replaced with standard strap lugs.  Swift’s proprietary system demands that you use the manufacturer’s strap, which is comfortable enough, but why impose restrictions?  Many birders prefer straps which take the weight off their necks, such as one made of soft neoprene, or a shoulder harness.

 The diopter adjustment is on the right barrel.  The movement of the diopter adjustment is fairly stiff and incorporates click stops, both of which keep it from migrating out of adjustment.

Eye Relief and Field of View

The Ultra Lites offer 19.5 mm of eye relief which worked well for me while wearing eyeglasses.  The solid eyecups twist up and have click stops allowing the user to adjust the amount of eye relief to his or her needs.

 Different people need different amounts of eye relief depending on whether they have deeply set eyes and on the type of eyeglasses they wear.  Swift is on the right track here in providing a generous amount of eye relief coupled with adjustable eye cups.

 If you wear eyeglasses you can get more from your binoculars by considering your birding needs when you purchase your next pair of glasses.  The amount of eye relief you need depends, in large part, on the thickness and size of your lenses and how they fit on your face.  If you are serious about birding and want to get the most from your binoculars, I suggest that you have your glasses made according to the following specifications:

·        Use hyper index (ultra thin) lens material

·        Ask for anti-reflective coatings

·        Use the smallest lenses that will accommodate your prescription

·        Select frames that fit as close to your face as possible.

·        If you wear bifocals or progressive lenses ask your optician to start the progression (from distance to reading) or the reading window of the lens about two millimeters lower than normal.

 The Ultra Lites have a close focus which goes down to 6 feet, which makes them fine for butterflies and dragonflies.

The angle of view is 6.5 degrees which translates into 328 feet at 1,000 yards which is certainly sufficient.  I would, however, love to see a wider field of view.  Two of the most important qualities in a birding binocular are brightness and field of view.  I lead many bird walks each year and find that beginners have the most difficulty finding birds with their binoculars.  A wide field of view makes it easier to find birds and easier to keep moving birds in your binocular field.  In a binocular in this price range a wide field of view will result in significant edge distortion, but (in my opinion) the image quality at the edges doesn’t matter as much as being able to find the bird.  Most users will ignore the edge distortion because they will instinctively move the bird to the “sweet spot” of the lens – the sharp center.

 Image Quality

The first thing you will notice about the Ultra Lites is their incredible brightness.  The advancements in lens coating technology in recent years have been very important in binocular design.  Especially important is the advance in manufacturing techniques which make it feasible to apply near state-of- the-art coatings to modestly priced binoculars.  Brightness is a major contributor to the apparent quality of the image and to the enjoyment of use.  The Swift Ultra Lites appear to be among the brightest bins I have tested in the mid-price range.  The color rendition appears to be quite natural.  Contrast is also very good.

 The resolution exceeds that of most roof prism bins that I have tested in this price range.  As one would expect (in a modestly priced binocular) the resolution falls off considerably at the edges.  There is an average amount of purple/green color fringing.  The field is much flatter in the center than I have come to expect in this price range.  Predictably, there is some barreling at the edges.

A Few Words On The Ultra Lite 8x42 Poro Prism

Along with the samples of the roof prism Ultra Lites, Allison Swift sent me samples of the poro prism Ultra Lites which merit a few words. The poros incorporate the same dual density armor and great looking color combinations as the roof prism model.  They also have the same eye relief and twist up eyecups.  They weigh only 3 ounces more than their roof prism cousins.

 What’s different?  Swift has incorporated a slightly elliptical shape into the armoring of the barrels which makes the poros fit like they were made from a mold of my hand.  I, frankly, love the way they feel and find them to be even more comfortable to use than the roof prism model.  The focus wheel is between the bridge elements which means that however you hold these bins, your fingers just fall on the focus wheel.  I should add a caveat here warning you that I have fairly large hands.  People with small hands will, undoubtedly, prefer the roof prisms.  Comfort is very important so please be sure to buy what is comfortable for you.

 Regarding image quality, it is still much easier and cheaper to make a great poro prism binocular than it is to make a roof prism.  In lower and mid-priced binoculars you should get the best image from a poro prism model.  A poro prism binocular is a simpler design, and does less damage to the light path.  The Ultra Lite poro is no exception.  I love the roof prism Ultra Lites and recommend them highly.  I would, however, choose the poros because they provide a superior image and because they are more comfortable for me.  The two models appear to be about equal in brightness and offer identical fields of view.  The poros are, however, significantly sharper, and offer a flatter field with less color fringing.  They are also about $50 less expensive.

By-the-way, Swift offers both Ultra Lites in 10x42 configurations.  I confess to being prejudiced against binoculars which magnify the image more than 8 times because I believe that brightness and field of view are more important than magnification.  I have also found that one can extract more information from an image that isn’t moving.  (Remember that ten power binoculars also magnify the movement of your hands ten times.)  For myself, I find that ten power bins are simply too tiring to use.  For whatever it is worth, most of the people who participate in my bird walks agree.  However, if you like 10s, you will find that the Ultra Lite 10x42s (poro and roof) offer the same high quality, relative brightness, and features as the eights.


I confess to have always been prejudiced in favor of Swift products.  Based on my experience with the new Ultra Lites (and a recent review of the Swift Audubon HHS) my strong inclination toward this company is well founded.   If you have large hands and don’t mind the sort of un-cool and bulkier appearance of poro prisms, I urge you to consider them.  Both roof and poro models offer images that are among the sharpest and brightest in their price range. Both models are among the best handling binoculars in their price range.