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Tele Vue Pronto


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Introduction

This article is a sequel to my previous Cloudy Nights article titled "The Tele Vue Pronto and the Living Star Atlas" published in March 2003. I will describe my continuing Tele Vue experience after obtaining a tracking mount for the Pronto and some new accessories. In particular I will discuss the Pronto's deep sky, double star, and planetary performance. I will also say a little about my background as an amateur astronomer and telescope user.

The Tele Vue Pronto is a 3-inch, "semi-apochromatic" refracting telescope. I love this optical and mechanical marvel. For a physical description of the Tele Vue Pronto, see my previous article described above.

Attack of the Clone

As I described in my previous article, I purchased my Pronto along with a Tele Vue Tele Pod altazimuth mount. The Tele Pod works well for low power observing and is very convenient and easy to use.

I began to want a German equatorial tracking mount for high magnification observing with the Pronto. Eventually, I pieced together a Clone mount from various transactions on Astromart. Clone mounts are Chinese imitations of the Japanese Vixen Polaris German equatorial mounts.

My particular Clone mount consists of a Chinese CG5 equatorial head combined with an Orion Telescopes SkyView Pro tripod. With its tubular steel legs, the Orion tripod is much more stable than the stock CG5 tripod. I am happy to report that this mount is very solid and is perfect for the Pronto. Vibrations dampen out almost instantly.

When using the mount, I fasten the scope to the mount with a Tele Vue adapter, which is basically a block of anodized aluminum. The Pronto's clamshell bolts to the adapter, and the entire scope attaches to the mount using one large threaded knob. I use one 7 lb counterweight to balance the scope.

Before observing, I roughly polar align the mount by pointing the front leg north in the direction of Polaris. If I'm ambitious, I will sight Polaris through the hole in the equatorial head.

The motorized mount tracks well. I currently use the single-axis Sky View Pro drive from Orion Telescopes. The drive tracks in right ascension only. I like the single-axis drive because I don't have to worry about the declination cord getting tangled around the equatorial head.

Placing a red-blooded Tele Vue scope on a Chinese mount is rather like towing a Harley with a Yugo, yet, for about the same price as a Nagler eyepiece, I have a stable mount that tracks well for visual astronomy. I have been very happy with the mount's performance. The CG5-Vixen Polaris type mounts are ideal for the Pronto. It may be a bit of overkill for this small telescope, but I would rather be "over" than "under" in terms of stability.


The Tele Vue Pronto and the Clone mount

Observing the Deep Sky

The Pronto will provide wonderful views of deep sky objects. It does particularly well on large nebulas and open star clusters. In the following section, I will discuss the Pronto's performance while observing nebulas, galaxies, and star clusters.

For deep sky observing, I use a 24 mm Tele Vue Panoptic and 13, 9, and 7 mm Tele Vue Nagler eyepieces. In the Pronto, these eyepieces produce magnifications of 20, 37, 53, and 69x. These eyepieces are all 1.25-inch format, which I find to be more convenient than 2-inch eyepieces. I occasionally break out a 2-inch, 35 mm Tele Vue Panoptic eyepiece for ultra-wide angle views of starfields, asterisms, and large deep sky objects.

The Pronto will reveal all members of the Messier catalog. Brian Skiff used his Pronto for the 2001 All-Arizona Messier Marathon and observed 109 Messier objects in one night. I have found that the two faintest Messier objects, M74 and M76, are easy to see with the Pronto under good sky conditions.

The Pronto excels at observing large, faint nebulas such as the Veil and North American. With a Lumicon UHC filter and a 35-mm Panoptic eyepiece, both arcs of the Veil Nebula are visible in the same field. This combination will also reveal the North American and Pelican Nebulas together in one view. Short focal length refractors are unique in having such wide-field capability.

M42, the bright Orion Nebula, appears as greenish folds of light surrounding the brilliant Trapezium of stars at its core. I especially enjoy the low power view of the Orion Nebula imbedded in the starry length of Orion's Sword. M8, the Lagoon Nebula, appears as amorphous grey masses mingled with dozens of stars. In particular, the view of the Lagoon and Trifid Nebula (M20) together in one eyepiece field is an exceptional treat.

Planetary nebulas resemble greenish stars in the Pronto's wide field views. The scope provides excellent views of bright planetaries such as M57, the Ring Nebula, and M27, the Dumbbell Nebula. In particular, M27 in the Pronto's low power field lies suspended against a Milky Way backdrop of myriad tiny stars. The nebula itself resembles a ghostly grey apple core. M57 is centered between the bright stars Beta and Gamma Lyrae in the constellation of Lyra. The low power field provided by the 35 mm Panoptic easily encompasses both stars, and the nebula is a small, grey, circular object lying between. Higher powers will reveal the Ring shape of the nebula. Using averted vision, I have also spotted the 13th magnitude star that lies close to the eastern edge of the nebula.

The large galaxy M31, the Andromeda Galaxy, resembles a cigar-shaped glowing cloud in the Pronto. The entire length of M31 is visible in the 5-degree field supplied by the 35 mm Panoptic. During one outstanding winter night in Indiana, I was able to trace the spiral structure of galaxy M33.

During an observing session in southeast Arizona, I located NGC 6822, Barnard's Galaxy, in the Pronto. This large, low-surface brightness galaxy is located northeast of the Teapot of Sagittarius. In the Pronto, the galaxy appeared as an elliptical patch of light.

Globular clusters appear mainly as partially resolved glows in the Pronto.

I never really appreciated the beauty of open clusters until I observed with the Pronto. The Pronto's pinpoint resolution of stars and wide fields combine to create the perfect instrument for observing large, splashy open clusters. At low power using the 35 mm Panoptic, nearly the entire Hyades cluster is visible in one view. The Pleiades and other Messier clusters are beautiful sights in this scope along with the Double Cluster in Perseus. On decent winter nights, the Pronto will display faint open cluster NGC 2158 in the same field with bright open cluster M35 in Gemini. M46 and M47 in Puppis provide a lovely low power duo in the 35 Panoptic. Higher magnifications will reveal NGC 2438, an 11th magnitude planetary nebula that lies superimposed against the background of M46.

Double Stars

I have spent many enjoyable evenings observing double stars with the Pronto. Double stars provide a nice departure from the planets and deep sky. Many are strikingly beautiful due to differences in color and brightness between the component stars. They also test an observer's skill and the quality of a scope's optics.

My favorite source of information for double star observation is The Night Sky Observer's Guide by Kepple and Sanner. For each constellation, the authors provide a star map and comprehensive list of observable double stars. I also use Brian Skiff's double star lists provided in Wil Tirion's Bright Star Atlas 2000.

The Dawes limit for the Pronto is about 1.7 arc seconds. The Pronto will generally split doubles wider than 2 arc seconds (") in separation unless there is a large difference in magnitude between the component stars. Examples of such unequal-magnitude pairs include Sirius (4.5"), Antares (2.9"), and Delta Cygni (2.5"). These particular stars are difficult for the Pronto. The scope will resolve Delta Cygni. I believe that I have glimpsed the dimmer components of Sirius and Antares during moments of good seeing, but I have never obtained completely unambiguous splits of these two stars. I have obtained good splits of unequal-magnitude pair Zeta Orionis (2.3") in Orion's Belt, and I am usually able to split Epsilon Bootes (2.8"). The component stars of Epsilon are magnitude 2.5 and 4.9, and, in the Pronto, the dimmer component of Epsilon appears as a bright colored knot imbedded within the first diffraction ring of the brighter primary star.

Doubles of near equal brightness are much easier to resolve. Epsilon Lyrae, the Double-Double, is a famous example of such a star. Three of the four component stars are close to 5th magnitude, and the fourth is magnitude 6.5. The Pronto will readily split the four components of the Double-Double at 69x.

Observing the Solar System

The use of a German equatorial mount has enabled me to better access the Pronto's planetary performance. In the next few paragraphs I will describe the Pronto's views of the planets, sun, and moon.

For planetary observing, I generally use a 7 mm Tele Vue Nagler and a 4 mm Tele Vue Radian eyepiece. At 69x, the Nagler provides small, but sharp, views of the planets. Combined with the Pronto, the 4 mm Radian creates a magnification of 120x. On good observing nights, I often use the 7mm Nagler with a Tele Vue 2.5x Barlow to achieve 171x.

I observed Venus frequently during its 2004 apparition. The planet's disk often displayed faint mottling. At half phase, the ends of Venus showed faint cusps or extensions. In early June 2004, I had lovely views of the extremely thin crescent Venus just above the horizon after sunset.

My best observation of Mercury with the Pronto was in the morning when the planet appeared as a small crescent. In the evening sky, Mercury usually appears as a prismatic blob due to low elevation and poor seeing.

The Pronto delivered my favorite views of Mars during its 2003 apparition. I often woke up early during the summer to observe the planet in the morning sky. Mars was a striking color in the Pronto, and I could easily see dark patches and the south polar cap.

As an example of the scope's performance on Mars, I include here some notes from the morning of June 27, 2004:

"Got up early to observe Mars again. I used the Pronto mounted on the Tele-Pod. Wonderful view. To the naked eye, the planet appeared as an orange beacon nearly due south. Even at low powers in the Pronto (18x, 37x), I could see a gibbous disk. My best views were at 171x. The south polar cap was bright and bordered by a parallel dark feature. The disk of the planet appeared mottled with numerous semi-dark features. I sometimes noticed two bright features on the edge of the planet almost due north and northeast."
Jupiter is very beautiful in the Pronto. At low magnifications, I feel as though I am approaching the Jupiter system in a spaceship. At higher magnifications, the scope will reveal the Great Red Spot and details in the North and South Equatorial Belts. I can usually count six to seven discrete cloud bands on the entire disk of the planet under decent observing conditions.

My most enjoyable views of Saturn in the Pronto are at 69x with a Tele Vue 7mm Nagler. The planet resembles a jeweled orb suspended in the blackness of space. I can easily see Titan and a few other satellites. The scope usually shows the Cassini Division in the rings. On good nights, I have discerned the dim silhouette of the Crepe Ring against the disk of the planet. At higher magnifications, the disk of Saturn displays faint banding.

The Pronto provides wonderful views of the sun and moon.

For white-light solar observing, I use a Kendrick full-aperture solar filter that features Baader Planetarium material. The filter provides a white, natural-looking solar disk. I particularly enjoy low power views of the sun suspended against a black sky.

The Pronto displays the sharpest and most detailed views of sunspots and bright faculae that I have ever regularly experienced. Granulation often appears as a subtle, speckled manifestation on the disk of the sun.

Tele Vue Pronto solar observing setup

Low power views of the moon are stunning in the Pronto, and I particularly enjoy seeing the lunar disk suspended in a wide area of sky. On partly cloudy evenings, I enjoy using the Pronto at low magnification to watch clouds flow across the face of the moon.

The Pronto will reveal all of the major features of the moon. At low magnifications, I am able to distinguish the subtle shadings and textures of lunar maria. At higher magnifications, tiny features on the disk are immaculately presented by the scopes sharp optics. The scope will easily show secondary craters around crater Copernicus and will also reveal small craters on the floor of crater Plato. I can usually locate three of these tiny Plato craterlets. I have also been able to see Rima Birt, a tiny rill close to the lunar Straight Wall.

New Pronto Accessories

Focus Lever

I was originally skeptical about the new Tele Vue Focus Lever and asked: Does the already smooth and precise Tele Vue focuser need such a device?

The first time that I used the focus lever, I couldn't help but smiling. The lever makes focusing very easy, and it enables me to focus in controlled, tiny increments. I generally use the lever with the Pronto equatorially mounted. I find it cumbersome to use when I have the Pronto mounted alt-azimuth on the Tele Pod.

The Focus Lever snaps in place when pressed against one of the "mag wheel" knobs of a Tele Vue focuser. The lever can be difficult to attach. I applied a tiny amount of white lithium grease to the prongs on the inside of the Focus Lever's base, and this helped significantly. When using the lever over a few evenings, it is easier to leave the base on and unscrew the handle for storage.

Stellarvue Carrying Case & Red-Dot Finder

Tele Vue's small scopes come with a padded soft case. I decided to replace mine after the foam insert began to shred. I purchased a Stellarvue C4 aluminum case as a substitute. I have been extremely pleased with this purchase and always felt that the Pronto deserved a better case.

The Stellarvue case features a large rectangular opening to hold the scope, two large circular openings for accessories, and some holes for eyepieces. The case has room for my solar filter, Red Dot Finder, Focus Lever, and the scope's 20 mm Plossl eyepiece. I am also able to leave the diagonal attached to the scope for storage.

The Stellarvue C4 telescope case

For aiming the scope, I originally used a Tele Vue Quik Point red dot finder. The Quik Point projects a red dot upon a darkened piece of glass, and an observer points the red dot toward the desired area of the sky. The Quik Point has two brightness settings, one for day use and one for night, and a dimmer knob set on an uncovered circuit board sandwiched between the battery and underside of the finder. While the brightness controls were useful, I found that the tiny viewing window made the finder difficult to use. I often resorted to swinging my head all around in quest of the red dot.

I eventually replaced the Quik Point with the Red Dot Finder sold by Stellarvue (see first photo). The Stellarvue Finder is a poor man's Starbeam, Tele Vue's deluxe finder. It features a larger viewing window, which makes it much easier to locate the red dot used in pointing the scope. The finder attaches to the same mounting block as the Quik Point and is tightened using two large knobs. This arrangement works really well, and it is easy to remove the Stellarvue finder for storage. One large knob controls the brightness setting, and all of the adjustments require no tools.

Summary

In this update to my previous Cloudy Nights article, I have discussed the Tele Vue Pronto's performance while observing the deep sky, double stars, and the planets, sun, and moon. I have also evaluated various accessories for the Pronto made by Tele Vue and other manufacturers. I am especially enthusiastic about the CG5 Clone mount, the Tele Vue Focus Lever, and Stellarvue's C4 aluminum telescope and Red Dot Finder.

Tele Vue announced in Spring 2004 that they had discontinued the Pronto and Ranger telescope lines. They have replaced these two scopes with the apochromatic Tele Vue-76 and Tele Vue-60. What this entails for Pronto owners I can't say, perhaps they will retain value as collector's items? I imagine that, fifty years from now, Tele Vue's scopes will enjoy the same collector's appeal as the old Alvan Clark scopes do today.

My Background

I have enjoyed amateur astronomy since the mid 1980's and it is my favorite hobby. I have owned two Dobsonian reflectors and a Celestron 8-inch Schmidt-Cassegrain. I now observe with a Meade 7-inch Maksutov-Cassegrain and the Tele Vue Pronto.

I am originally from Indiana, and after college spent seven years in Arizona and was a member of the Saguaro Astronomy Club. I attended many observing sessions in the Arizona desert. I have since spent the last two years in Northern Indiana and live in a small town with decent skies

I enjoy all aspects of observational astronomy from naked eye observing to deep sky and planetary observing through telescopes. I devoted my first years of observing to the deep sky, especially when I lived in Arizona. In 1998, during the All-Arizona Messier Marathon, I observed 108 Messier objects in one night using an 8-inch Dobsonian and Sky Atlas 2000. Since moving to Indiana, I have devoted more observing time to the moon, planets, and double stars. I still pursue deep sky observing when I have a conjunction of clear weather, moon-free sky, and free evening.

I have no undisclosed interest in Tele Vue or any other vendor that I have mentioned in this article, and I have purchased my equipment via normal channels. All of the photographs that I have included in this article are my own property. I hope that this article has been helpful and informative. Please contact me at the above email address if you have any questions or comments.




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