TV-85 reviews

    Here are some excerpts from a review of the TV-85 in the September 1998 Sky & Telescope magazine:

    "The TeleVue 85 is a real work of art . . .
Focusing the TeleVue 85 is truly a pleasure. The high-quality, 2-inch, rack-and-pinion focuser is buttery smooth . . .
Most of my visual tests were done in early May, when a waxing crescent Moon and a generous amount of haze limited naked-eye stars to 4th magnitude and brighter. The seeing, however, was quite good and ranged between 7 and 9 on a scale of 1 to 10. My tests were made with the scope on either a Losmandy GM8, G11, or a Vixen Super Polaris equatorial mount. All offered stable, vibration-free views.
One critical visual test of the optics involved checking a bright star's image inside and outside of focus. I did this with a TeleVue 15-mm Panoptic eyepiece used with and without TeleVue's new 5x Powermate "Barlow." In each case the scope showed textbook-perfect star images on both sides of focus, signs of a well-corrected lens.
Dawes' limit states that an 85-mm objective should resolve double stars separated by as little as 1.3 arcseconds. My first double-star test was Gamma Leonis. This beautiful pair has a 4.4-arcsecond separation and components of magnitude 2.2 and 3.5. It is considered easy for small telescopes. I centered the star using a 35-mm Panoptic eyepiece, which yielded a tack-sharp 17x image. Switching to a 7-mm Nagler upped the magnification to 85x, which easily split the double. I then tried the 15-mm Panoptic and 5x Powermate to obtain 200x. The stars were sharp Airy disks surrounded by extremely clean concentric diffraction rings. A wonderful view!
My next target was the 4th-magnitude double Gamma Virginis, with a 1.7-arcsecond separation. The stars were easily split at 200x. Pushing further, I tried the 7-mm Nagler with the Powermate for 428x. The stars appeared sharp and clean with perfect Airy disks surrounded by concentric diffraction rings. The only image degradation was due to the seeing, not the optics. Truly awesome! I had the same visual impression, both at 200x and 428x, when I turned the scope to the 1.6-arcsecond double Xi Ursa Majoris. Incredible!
The tightest double I tried was 35 Comae Berenices. While I was not able to split the 1.1-arcsecond components, at times I felt the star looked elongated.
While a typical eye can resolve Dawes' limit with as little as 12x per inch of aperture, most observers are more comfortable with 20x to 30x and some even prefer 50x or more. Using the TeleVue 85 at 428x called for a remarkable 125x per inch of aperture! But that's not the end of the story.
The biggest surprise came while I was viewing Epsilon Boötis, a beautiful blue and yellow, 2.9-arcsecond double. With the star riding high in the east, I fitted my 2.5-mm Vixen Lanthanum eyepiece to the Powermate. This is equivalent to a 0.5-mm eyepiece, yielding a magnification of 1,200x with the TeleVue 85. Before looking into the eyepiece I considered this an act of futility. But the view almost blew me off my chair! When the seeing allowed, the star images had classic diffraction patterns with an obvious dark separation between the rings.
After the double stars, my next target was the Moon, since I wanted to test the scope for signs of color aberration. If any was present, the Moon's bright limb projected against a dark sky would be where I'd find it.
The evening was very steady with the nearly first-quarter Moon high in the western sky. I began with the 20-mm Plössl. The 30x view was incredible with the brilliantly lit Moon standing out in sharp contrast against a jet-black sky. There were no signs of internal reflections to degrade the image.
Upping the power to 40x with the 15-mm Panoptic gave an even better view. Numerous craters along the terminator were razor sharp and the ghostly bluish glow of earthshine was clearly visible, a breathtaking sight. Next I added the Powermate for a 200x tour of the lunar surface. Mountain ranges, rays, rilles, and microscopic craters stood out in sharp, bold relief. For nearly an hour I watched mesmerized as the shadow cast by the rim of Theophilus moved across the crater's floor. Turning to the lunar limb, I could make out just the slightest violet coloring. It was so faint that unless they were specifically looking for it most observers would likely have missed it.
Deep-sky views with the TeleVue 85 were equally impressive. At 17x with the 35-mm Panoptic, stars in the open cluster M44 shone like diamonds against a dark background. Nevertheless, moonlight and haze prevented pushing the scope to its limits on faint, diffuse objects such as nebulae and galaxies.
In addition to being a top-rate visual instrument, the TeleVue 85 doubles as a very high quality lens when coupled to the optional field flattener, which increases the focal length slightly to 660 mm (f/7.8). This combination delivers a field about 3° by 2° on 35-mm film, which is perfect for photographing objects such as the Lagoon and Trifid nebulae, the Pleiades, and the Andromeda Galaxy. Photographs made without the field flattener showed elongated star images as little as 1° from the center of the image. With the flattener, however, stars were very much sharper. In my opinion the optional field flattener is a must for those interested in doing serious astrophotography.
The TeleVue 85mm f/7 APO refractor is truly an incredible instrument with superb, well-corrected optics. The scope's mechanical construction is also first class all the way. Whether you are traveling half way around the world to photograph a total solar eclipse or just casually observing from your backyard, the TeleVue 85 offers today's amateurs an extremely powerful, compact instrument capable of delivering stunning images of the universe around us. This scope is a real gem!"

    Here are some additional excerpts from a review of the TV-85 on Cloudy Nights.com:

    "If you have any interest at all in nature viewing (and of course you do if you like astronomy), you really should have a look through a TV-85. Looking at common birds like Jays and Cardinals is like seeing the bird for the first time. I'm lucky that I live close to Van Cortland Park, where there is a nice mix of woodland and pond environments. It's also very easy to just put the 85 over my shoulder and take it on the train down to Central Park where there is major flyway and migratory route, not to mention many kinds of waterfowl in and around the reservoir. Minutes turn quickly into hours with the TV-85 and a Panoptic eyepiece.
As for astronomy, the scope is simply a joy to use. I sing in the Met Opera Chorus and getting home late at night after performing some of the great works of Wagner, Verdi, etc. I'm a little wound up! Even a quick half hour session on my roof does wonders for my state of mind. I also have a very nice 6" Dob now, but it's rather inconvenient getting in around mid-night to wait a half-hour or so for the scope to cool down. Of course, that's not an issue with the TV-85. I peck my sleeping wife on the cheek, grab my scope and Telepod and I'm on the roof observing in minutes.
I just bought the Nagler 3-6mm Zoom and it's a perfect match in the 85. It gives a range of 100-200x and the scope on a steady night can easily handle this on the moon and planets and of course, doubles. Jupiter's Red Spot and 4 clear bands are the norm. The first time I saw a shadow transit on Jupiter, it looked like the Almighty had put a crisp, black dot on the planet's surface with a huge fine-point marker! Saturn is absolutely gorgeous with the Cassini Division a crsip, black line available totally circling the planet at the moment. I've seen 4 moons with direct vision.
Looking at the brighter clusters and nebula in a Panoptic is something I'll never tire of. M45, M44, M35, M36 and others have that almost 3-D quality to the image. The Double Cluster is spectacular with stars everywhere and great color contrast. The Trapezium is easily resolved even at 32x and the stars are crisp points of light suspended in the gas cloud. Amazingly, the TV-85 reveals as much of the gas cloud as does my 6" Dob. Contrast does matter after all! At 75x, I've clearly seen the E star in the Trapezium and I'm sure on a good night I can get the F star as well, though maybe not at that power. Rigel's companion shows up clearly at 75x as well and all 4 components of Sigma Orionis are easy. The Winter Albireo is stunning with great color contrast. I can't wait for the real thing in summer! The comet Ikea-Zhang is a spectacular sight now even in binoculars, so I don't have to say how great it looks in the TV-85. But it's gorgeous. Please make it a point to try and see this comet as it continues to brighten. I can see that I'll be getting a serious lunar atlas, because the amount of detail that I can see even on the 5 day old moon is stunning. I'll be counting craterlets in Plato this weekend in the Nagler Zoom!
I could go on, but you get the gist. I'm very, very pleased with this telescope. It has fantastic optics, it's very portable and versatile as far as mounts and accessories, and 85mm is a nice amount of aperture for the majority of observing that most amateurs engage in. I'm aware that the price of the TV-85 is not unsubstantial, but I can honestly say that not once have I thought about that when I'm at the eyepiece. I'd be willing to bet you won't either!
Oh yeah, did I mention that Castor at 200x looks like a pick-up truck's headlights coming at you on a country road at midnight?"

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