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Tele Vue Ranger Review

Tele Vue’s classic ‘Ranger’ small refractor from the 1990s uses the same optics as the astronomy-oriented Pronto, in a smaller and lighter package more suited to terrestrial use (but perfectly good for astro’ too). It was widely adopted by birders and Tele Vue even made a stay-on case for it.

The Ranger employed a unique sliding bar, ringless mount and a drawtube/helical focuser combination that was simple to use and helped keep weight down, which many loved and some didn’t. The Ranger was eventually discontinued in favour of the smaller and more sophisticated full-apochromat TV-60, but the newer scope continued the Ranger’s mount and focuser.

Between them, the Pronto and Ranger introduced numerous people to astronomy in the Nineties and re-booted the interests of many others (self and Ed’ Ting included). I owned the Pronto, but I thought that twenty years on it was time I took a fresh look at the Ranger to see how it stacks up in a modern world of cheap Chinese small refractors.

At A Glance

Telescope

Tele Vue Ranger

Aperture

70mm

Focal Length

480mm

Focal Ratio

F6.8

Length

40cm

Weight

1.5 Kg (incl dovetail mount rail)

 Data from TeleVue/my own measurements.

Design and Build

Like the Pronto, the Ranger was proudly made in America and has an artisanal feel to it mostly gone from the market now. This was an item produced in reasonable volume, but retains an ATM feel – the way a really skilled engineer might make a little scope for himself. It’s something I think people increasingly value in Tele Vue products.

Unlike the TV-60 which is unique among TV’s range, past and present, the Ranger has features that connect it with other Tele Vue scopes. The tube has the familiar ivory pebble powder coat; the combined cell and hood are a miniature of the Renaissance’s; the metal parts are finished in contrasting glossy black-anodising (long replaced with satin in newer TVs) just like my TV-76’s.

Ranger with its contemporary small APO – Takahashi’s FC-60. Tak’ is longer; they weigh the same.

Optics

The Ranger shares its 70mm F6.8 (480mm F.L.) doublet lens with the Pronto. The spec says it uses ED glass, but a famous telescope designer has said it was a cheap ED that delivered only modest benefits in false colour correction.

In the past I’ve agreed and said that the Ranger and Pronto are achromats. If so, then they perform better than a 70mm F6.8 achromat – more like one at F8 to F10. Still, the Ranger and Pronto are not apochromats like the replacement TV-76 and TV-60. We’ll settle with describing them as a semi-apo towards the achromat end of the scale.

Interestingly, the Ranger lens has no visible foil spacers. That would usually mean a lower-performing cemented design, but investigation with a laser reveals a larger air-gap – a technique often used to deliver improved correction (for false colour, but potentially field curvature too).

Tube

The TV-60 that directly replaced the Ranger has an all-CNC tapered tube with integrated sliding dew-shield. The Ranger was much more conventional. It has a fairly long aluminium body, coated in pebble ivory like almost every other Tele Vue all the way up to the NP-127 (though many birders chose the optional green pebble coat, whilst some opted for living-room-classy brass).

Although the Ranger is about five inches longer than the TV-60, it is virtually the same weight: 1.5 Kg including the sliding dovetail. It’s also exactly the same weight as Takahashi’s FS-60C including its clamshell. This low weight gives the Ranger a significant usability advantage compared with the optically-identical but twice-as-heavy Pronto.

The Ranger’s dew-shield is short and fixed and combines with the lens cell. The lens is fixed into the tube with bolts and isn’t collimatable. The focuser threads neatly on. Unlike a Pronto (and many other Tele Vues) which has a screw-in metal cap that takes ages and screeches, the plastic lens cap just clicks into place like a camera’s, even though the hood is internally threaded.

Internally, like all Tele Vues, the Ranger has no baffles. Instead it’s lined with flocking material that looks like coarse sandpaper painted flat black.

Focuser

Whilst the Pronto had a single-speed r&p focuser with the famous ‘mag’ wheels, the Ranger uses a more unusual system with a drawtube for coarse focus and a helical for fine. The biggest downside is that it doesn’t allow for 2” eyepieces, unlike the Pronto’s.

Some people didn’t like this focusing system that carries on into the TV-60 today. I’m not one of them. For one thing it gives the Ranger loads of focus travel – so much that astrophotography is possible with no extra extensions. For another, you effectively get a fine focuser which the Pronto didn’t have unless you paid for an aftermarket unit and managed to fit it without losing a shim or cross-threading a screw (as many did).

The drawtube and helical unit are simple but very robust and well-engineered. They work well with no slop, but after a few years the grease goes hard and you need to disassemble the helical part and clean then re-grease it. I explain how here in a separate article elsewhere on this site.

The focuser drawtube has machined-in ridges and is painted matte black to kill internal reflections.

Focuser with drawtube retracted and extended.

Mounting

The Ranger, like the later TV-60, avoids the Pronto’s heavy clamshell in favour of a sliding bar to which the tube fixes with a clamp. It’s a system that makes the Ranger very easy to balance and saves weight

The sliding bar has the usual TV pair of ¼-20 threads on the bottom that fits Tele Vue’s Panoramic mount and a single ¼-20 thread for a substantial photo head. Or you can affix TV’s own Vixen dovetail for Vixen and Skywatcher mounts, which I did to mount the Ranger on a Vixen SX2 for testing.

TV-60 experience suggests the Ranger will work much better on a Tele Vue Panoramic mount than their heavier scopes do.

I mounted the Ranger on a basic Manfrotto fluid head atop one of Berlebach’s cheapest and lightest ash tripods. The result was a one-hand grab-n-go outfit that worked really well. Having adjusted the sliding bar to the perfect balance point, I was able to slacken the fluid head to get really smooth panning. I found it stable up to quite high powers and ideal for quick looks at the Moon from around my drive and garden. This is where the Ranger beats the Pronto, which was too heavy for the same head.

Incidentally, Tele Vue once made a hardwood table mount for the Ranger called the ‘Executive’ mount. It’s a rare item I’d love to own.

Ranger on Vixen mount with TV-Vixen dovetail plate attached to its sliding bar.

Ranger mounted on a lightweight fluid photo head.

Accessories

Various accessories were available for the Ranger, including:

·        A padded and semi-waterproof stay-on bag

·        A rubber lens shield that screwed into the threaded lens hood

·        The Quick Point red-dot-finder that attaches via a small dovetail adapter (which itself screws into a slot atop the Ranger’s visual back)

·        A Vixen mount dovetail adapter that screws into the 1/4-20 threads on the Ranger’s mount bar

The Ranger was supplied with a 20mm Plossl; other focal lengths are obvious accessories.

Ranger in its stay-on case, ready for birding!

Ranger makes a very decent terrestrial telephoto lens.

In Use – Daytime

True to its multi-use spec’, the Ranger makes an excellent daytime spotter or birding scope. With a mirror diagonal, it may deliver a left-to-right reversed view, but sharpness and resolution are at levels few prismatic scopes can deliver. Colours are vibrant, detail excellent.

Crimson Whitethorn berries on branches 50m away have an almost hyper-real level of clarity and detail at low power. The same is true of autumn leaves on the beach tree opposite, or waders out on the bay sands.

At 32x, I watch a crow stalking about in the fields opposite with an extreme clarity no binoculars, no prismatic scope, can ever give – tiny droplets of water gleaming amid the feathers. This is why birders once valued the Ranger and Pronto so highly.

With flat-field eyepieces like Naglers, the view is undistorted right to the field stop and even a Tele Vue Plossl deliver a very sharp view across almost the whole field.

However, the Ranger does have limitations. Watching a Jackdaw sitting on a branch partially silhouetted against silvery bay waters, at 32x with a 15mm Panoptic, the black feathers are rimmed with a touch of purple and green. My usual test of branches viewed against the sky at ~100x yields a wash of violet in focus.

It’s the same with anything that has very high contrast. But I wouldn’t want you to think this is a deal-breaker; for most things at modest powers it is not and the Ranger delivers a great daytime view. But it’s worth noting that the Ranger shows much more false colour than a TV-60.

So, in bright conditions the Ranger is best at powers not much over 50x. Beyond that, the view is still sharp and detailed, but now bright objects are creating quite a lot of purple false colour that is starting to wash-out contrast.

Another issue is that short lens hood: skylight washes onto the lens and washes out the view. Mine came with the rubber lens hood accessory and that’s why.

The Ranger makes an excellent telephoto lens during the day. The focuser drawtube has so much travel you don’t need an extension tube for targets further than about 10m, making photography very easy with a T-adapter and a 1.25” nose-piece. Results are good, but again high contrast areas do show more purple fringing than through a true apochromat.

In Use – Astrophotography

Despite the 1.25”-only focuser, the Ranger makes an adequate casual astrograph. Images are quite flat across an APS-C sensor, stars only distorting at the edges. Likewise, illumination only drops off in the corners.

Now, though, that semi-APO lens shows its true colours, literally, because white stars show quite a lot of violet bloat. The Pleiades, for example, are much more colourful than they should be. But for galaxies, brighter nebulae and clusters, the Ranger’s sharp optics and reasonably fast f-ratio produce good results. As usual the subs below are straight from the camera.

For its modest image scale, the Ranger takes a good sharp image of the Moon.

M31: Fuji XM-1 APS-C: 85s at ISO 3200.

M45: Fuji XM-1 APS-C: 42s at ISO 3200.

Cropped Ranger image of the Moon with slightly boosted contrast.

In Use – The Night Sky

General Observing Notes

The thing that really hit me using the Ranger, after reviewing several clever-but-complicated Borgs and Takahashis in the same size range, was just how wonderfully simple and fun it is to observe with. No messing with interchangeable visual backs, yet there is loads of focus travel for any eyepiece and getting a good balance is super easy – just slacken the clamp thumb screw and move the tube on the bar.

The Ranger’s short length means the eyepiece is always in a convenient position and its light weight makes handling easy too. The short focal length means you mostly don’t need a finder.

The Ranger only takes 1.25” eyepieces, but this really isn’t much of a disadvantage because a 32mm Plossl or 24mm Panoptic give 3.2° of true field, which is more than enough for most things.

Cool Down

A light aluminium body and simple doublet lens means the Ranger cools super fast and delivers good views straight from a warm house.

Star Test

All Tele Vues are good optically, but oddly this Ranger has a perfect star test with identical Fresnel rings that zing out either side of focus. There is just a little violet out of focus in the star test to confirm this isn’t a full-apochromat.

The Moon

Just after full, with Mare Criseum starting to be picked out with terminator shadow, the Moon through the Ranger surprised me. A cold hard ball full of detail was much as I expected at 32x. At 96x with a 5mm Nagler it was still a great view, albeit with a purple fringe off the limb. At 137x with a 3.5mm Nagler, the view was still good. Yes, the purple was now bright and obvious, but it wasn’t washing out the detail and everything stayed sharp and contrasty. Short focus achromats don’t do that, Tele Vue’s own Renaissance included, washing a lot more violet across the Moon’s craters at powers over 100x.

Back at the Moon, I enjoyed the embayments and cliffs and craterlets around Mare Criseum, bright Proclus with its odd shape. Nearer the limb, I could make out Hummocks on the floor of Gauss, the central peak in Hahn. I found the Messier twins and their bright rays. Next night, the strange straight rille like a clock hand in Petavius was easily resolved in poor seeing.

One frosty November Monday morning of excellent (8-9) seeing, I got up early and looked out on a last quarter Moon, high in the sky just off the meridian, with Albategnius on the terminator. With a 3.5mm Nagler giving 137x, I could make out the craterlets like a string of beads along Rima Hyginus and Rima Ariadaeus disappearing into the lunar night.

The view was sharp and full of detail: running down the terminator, I enjoyed Mons Piton shining alone in Mare Imbrium near the ‘ring wall’ of Archimedes, the sharp peaks of the Apennines, the slumped walls of Tycho in extraordinary detail. Clavius and its arc of craters.

On another night, a bright gibbous Moon did show quite a lot of false colour at 137x with a 3.5mm Nagler, though, where an FS-60Q did not.

Increasing magnification to 192x with 2.5mm Nagler, the view stayed surprisingly sharp. But now a wash of pale lilac started just back from the dark limb, spoiling the view and reducing contrast. In this respect, the Ranger outperformed the TV Genesis, but the Takahashi fluorite doublets alongside could take higher powers in the excellent seeing and without that wash of false colour.

Overall, and despite the purple rinse at high power, the Ranger gave a very satisfying view of the Moon.

Mars

I caught Mars low in the dawn sky at the beginning of an opposition year when it was quite bright but just 3.8” in size. The Ranger showed a nice little orange disc with just a trace of false colour at 96x with a 5mm Nagler.

Venus

At 96x with a 5mm Nagler, Venus at Magnitude -4 in a bright dusk sky showed lots of violet and purple either side of focus.

In focus, the 14 arcsec gibbous disk was crisply defined, but had a broad ring of muted purple around it. Interestingly, compared with a Takahashi FS-60C, the Ranger generated much more false colour but defined the bright planet more clearly.

Deep Sky

Early before dawn one frosty November morning, Gemini, Orion, Leo and Auriga hung in front of my balcony twinkling coldly. I set the Ranger out and went deep sky observing – honestly more fun than I’ve had with a scope since I can remember.

Swapping between just three (of TV’s own) eyepieces were all I needed – a 32mm Plossl (my most used eyepiece for 20 years), a period 15mm Panoptic and a 5mm Nagler T6 giving 15x, 32x and 96x respectively. But even just the standard 20mm Plossl, included with the Ranger new, would give great deep sky views at 24x.

The Ranger’s optics give a very flat field with the perfect lens squashing all the light into the tiniest stars across the field to give strong star colours. For deep sky, false colour just doesn’t intrude visually, even on brighter O-A stars.

I flitted between Orion’s sword, the diamond Pleiades, brilliant but faintly misty, Auriga’s clusters, the Double Cluster in Perseus. I split Castor and enjoyed some simply beautiful star fields. Everything looked gorgeous, more so than in a 60mm because the Ranger is grabbing 36% more starlight.

With Rigel low in mediocre seeing and strong moonlight, I was still able to pull Rigel B out of the glare, better than in an FS-60Q alongside. On another night, I just about split the Double Double in terrible seeing too.

I had a good view of the Ring Nebula, it’s shape easy to pick out with averted vision through a Nagler 7mm at 69x – much better than the FC-60, with a third less light gathering aperture and that uncoated fluorite element. Similarly, globular cluster M15 was easier to pick out from Moonlight through the Ranger’s 70mm ED lens than the FC-60’s 60mm fluorite one.

Here, I felt, I could really channel Al Nagler: astronomy at its simplest and most rewarding. The Ranger is a very nice deep sky tool.

Tele Vue Ranger vs TV-60

TV-60 and Ranger – photographed in January almost exactly a decade apart.

This is a most interesting comparison for me, because Tele Vue replaced the Ranger with the TV-60 and you would expect that the TV-60 would be better all round, but as I’ve hinted that’s not quite true.

The TV-60 is certainly smaller than the Ranger, but they weigh the same. The TV-60 has near-perfect apochromatic optics, whilst the Ranger is at best a semi-apo. But for astronomy the Ranger generally takes high powers just as well, albeit with more false colour that spoils the view of the Moon a bit above 100x.

The TV-60’s lack of false colour does allow higher powers during the day, but 36% greater light gathering area and 13% higher resolution generally means the Ranger performs rather better at night.

An extra 10mm means a lot for this size of telescope and the Ranger gives significantly better views of DSOs and potentially resolves more detail on the Moon (though in a less perfect manner).

The clincher for me is that I prefer the classic white tube of the Ranger. It costs a lot less used, too.

Unless you really need the tiny size of the TV-60, or will use it mainly for the Moon, I’d recommend the Ranger.

Summary

Big aperture; massive goto mount; quadruplet fluorite; 100° monster eyepieces; huge rotatable focuser: the Ranger is a reminder you really don’t need those things to enjoy astronomy. In contrast, the Ranger is gloriously simple, relaxing to use and extremely versatile; it was thoughtfully designed that way.

The Ranger has beautifully sharp optics and very high quality mechanicals. It’s likely to be rugged too (this one is still perfect 20 years on). At current prices it’s an absolute bargain – much cheaper than a truly just-an-achromat Borg 60mm, for example.

However, despite the quality of its optical figure, the Ranger is, if not an achromat, a very modestly corrected semi-apo. Still, this seems less of an issue for astronomy than for terrestrial use – it will happily take high powers on the Moon which short-F achromats won’t. Even during the day, for birding or nature viewing, spotting-scope magnifications (i.e. up to 50x) give perfect views.

So, I would be very happy with the Ranger as my only quick-look and casual travel scope, I just wish TV had put the TV-76’s apochromatic optics in the Ranger instead or turning it into a more limited 60mm format for the TV-60.

But the bottom line is that I loved the Ranger for astronomy and for birding too. I just enjoyed the view, on everything I looked at – thanks Al’.

I really like the Ranger: pure essence of Tele Vue. In some ways I prefer it to the TV-60, yes for its classic looks but also because it grabs more light for deep sky.

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