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Home > Reviews > Telescopes > Refractors > Battle of the High-End refractors
Battle of the High-End refractors sought the finest portable refractor. I own a 2001 TeleVue85 (600 mm FL f/7.0), of which I am very fond. At a star party in Arizona in April, I had been stunned by the clarity and beauty of the images an Astro-Physics Stowaway provided; I thus narrowed my field down to TeleVue and Astro-Physics, excluding Takahashi and other makes on the basis of specimens seen at star parties. I sought my answer by a direct comparison. A friend was offering a 2002 Stowaway (92 mm aperture, 604 FL, f/6.6) for sale; he joined me for the test session. To this we piggybacked my TeleVue85 onto a Gibraltar mount equipped with Sky Commander. Having calibrated the Sky Commander to Polaris and Antares, no finder was needed. We used pairs of Takahashi LE-30 mm, TeleVue Panoptic 19 and Nagler 9 mm eyepieces, with a TeleVue enhanced diagonal for the TeleVue and an Astro-Physics Maxbright for the Stowaway. For wide fields we used a 22 mm 2 inch Nagler. The magnifications were 20x, 32x, 66x for the 1.25 inch eyepieces, 27x for the 2 inch. A single 3-6mm Nagler provided higher powers (100, 120, 150, 200x). We used one eyepiece with a Meade moon filter for lunar views. The ‘scopes had been in my garage during the day and were at ambient temperature. We observed Jupiter, the Moon, and three double stars (The Double-Double, Polaris, Mizar), from 9-930; frustrated by low clouds, we went inside and returned from 1130-0200. Atmospheric conditions were much better in the second session, we observed Messier objects in Sagittarius and Hercules. On very bright Jupiter the TeleVue kept better color than the Stowaway, details were clearer with the smaller aperture ‘scope. Performance differed more with the Takahashi eyepiece than with the others, TeleVue’s eyepiece quality is clearly superior to Takahashi’s. The Jovian moons were rounder and had more substance on the Stowaway. Markings on the planetary surface varied more with seeing than between the telescopes, especially at magnitudes of 150-200x. The Great Red Spot was not clearly seen even at 200x. There was more contrast between the planet and the blackness of space with the TeleVue, which was our preferred telescope for this object. Looking at craters near the lunar terminator, with the filter in place, the Stowaway offered a greater dark-light contrast on the moon and relative to space. Sadly, there were no stars to occult. Approaching the lower limb of the moon, the TeleVue had a deeper depth-of-field and required less refocussing. The fine focusser on the Stowaway is really outstanding, providing superior certainty of focus. We agreed that the Stowaway was more pleasing for viewing the moon. Looking at Messier objects, it was easy to see differences between the small ‘scopes. Consistently, the TeleVue showed diffuse objects (for example the Dumbbell nebula) to better advantage, they were more readily seen and had more definition. The Stowaway showed more contrast and more stars in pinpoint clusters, for example M13. Three times I did not see a low intensity object on the Stowaway but found it on the TeleVue, then could see it on the Stowaway; this may be a bias, however, as the Stowaway was used as the primary scope for the Sky Commander, so an object centered on the Stowaway would be a third of the way to the edge on the TeleVue and thus in a more sensitive portion of the retina. We disagreed as to which telescope was better on double stars, curiously the Stowaway owner thought the TeleVue provided clearer distinctions and I thought the Stowaway was better. The grass is always greener... On wide, busy star fields (including the double cluster in Perseus) I found some out-of-pointiness laterally with both scopes when using the Takahashi eyepiece, the Stowaway was worse. Also, some spherical aberration was noted with both telescopes, the limb of the moon was slightly distorted near the edge of the field. This was more evident with the TeleVue; the next day I looked at brick chimneys with both telescopes and confirmed this observation. Taken as a whole, the TeleVue and Stowaway varied more in style than in substance; I found less difference between them than I had expected, and the differences went both ways. I think that an open-minded observer could go on and on between these two fabulous telescopes, always preferring the one in use at the time. One is reminded of the barmaid at the Spouter Inn in Moby Dick, endlessly asking "Clam? Or Cod?" as she offers chowder to the patrons; both are good, and the choice will ultimately be one of taste. Do I have my answer? Yes and No! I preferred the Stowaway for the objects I like most, globular clusters; but the difference was not universal over all classes of objects, and the seller was asking more than I cared to pay, so I took my TeleVue85 to Mauna Kea. We had a great time there. But if I can find a used Stowaway at a reasonable price, I just might buy it for my next trip -– perhaps after enjoying another night or two of testing. Click here for more about the TeleVue TV 85. -Ed. |
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