TeleVue 102 Refractor Telescope Review
I have owned a TeleVue 102 refractor for about a year now and feel I have used it enough to write a review for the NightTimes. This telescope has a two-element lens with an aperture of 102mm and a focal ratio of 8.8. TeleVue makes refractors in apertures ranging from 60mm to 140mm. I believe the 102 is designed to be a lower cost alternative to the company's 101mm telescope. While they both have similar apertures the 101 has two additional lens elements near the focuser. These lenses further improve the image by reducing color fringing (chromatic aberration) and flatten the field for photography. Since I was interested in a telescope for visual observations of the sun and moon I decided on the 102 instead of the 101. If you look closely at the photos in this article you may notice the telescope looks shorter than the one in TeleVue's advertisements. This is because my particular telescope has a tube five inches shorter than a regular telescope of this focal length. I needed this in order to mount my solar filter.
The telescope is very well made. Starting at the front, the lens cap is a solid plate of aluminum that threads into the front cell. I really like this more than lens caps that slide on. On one of my other refractors I am always afraid the edge of the lens cap will hit the glass if it should fall off as I'm taking it out of the case (I now tape the cap on to make sure no accidents happen). After unscrewing the cap, the lens shade of the TV102 can be pulled forward. It is felt lined to make the sliding action smooth and to help block unwanted light from reflecting off the side. The purpose of a sliding lens shade is just to make the telescope shorter when it is put into its case.
The tube itself is thick seamless aluminum with a textured white finish. It looks like powder coating because I have accidentally banged it a few times and I didn't make any scratches in it. The texture also hides fingerprints well. The tube is attached to the mount with a felt lined aluminum ring about three inches wide. The mounting ring is kept on the telescope all the time. To balance the telescope I loosen one thumbscrew and slide the tube up or down. It is quick and easy. The mounting ring has two flat areas machined into it to accept a finder scope or sighting device.
The mount recommended for this telescope is the TeleVue Gibraltar. This is a simple non-motorized fork mounting with an adjustable height wooden tripod. Small brass knobs can be tightened to adjust the amount of friction in the movements. Honestly I'm a little disappointed by this mount. The motions up and down and left to right are smooth but I feel the whole mount is built too light. Vibration is constant whenever the focuser is touched. It works well at magnifications of 50X or less but anything higher and the image shakes too much for me. That said I do use the mount a lot because it is so easy to set up and carry. I usually keep the telescope set up next to my patio door and can easily carry the entire scope out the door in one piece. I would like to buy a heavier mount some day and keep the Gibraltar for those nights when I just need a quick astronomy fix.
Optically the telescope is very good. I have no complaints about the image. I can see no color error in the lens when looking at the moon but more importantly the figure on the lens appears excellent. Often many people argue about how one telescope has better color correction than another but I feel it's the figure that makes or breaks a good telescope. When I talk about figure I mean how well the lens is shaped not what it is made of. A poorly figured telescope will not come to a sharp focus or will show distorted star images. To my eye the TeleVue 102 shows perfect star images. I tried star testing the telescope and it looked good but then again even with my 20 years of telescope experience I do not feel qualified to judge a star test. I do know that I am very pleased with the views of the moon, planets and double stars. It is only a four-inch telescope though. Certainly someone interested in hunting down faint galaxies will not be pleased with this instrument. Most of my observing time is spent on the sun, moon and planets so this telescope fits my lifestyle perfectly.
I would recommend the TeleVue 102 to an experienced observer looking for a small lightweight telescope of high quality. It would also make a good beginners telescope if the limitations of the aperture are realized. I think the Gibraltar mount is something that should be tested before purchase. Some people may find the mount wonderful and others may not. Purchasing the right telescope is a very personal decision. The best thing anyone can do is try a telescope out at one of our meetings or star parties and see if it fits their personality. Overall, I'm very pleased with the TeleVue102 and plan on many years of fine observing.