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Tele Vue Renaissance Review

Everyone loves a nice retro brass scope for that clubby den or seaside terrace. Trouble is, most brass telescopes are … well, rubbish really. Which, in fact, is where Tele Vue came in all those years ago – supplying brass telescopes that really worked.

One of Tele Vue’s early brass telescopes, one that innovatively used the quadruplet Petzval camera-lens design, since much copied, was the Renaissance.

The Renaissance on test here is a commemorative edition for the return of Halley’s Comet in 1986. Even though it’s an early example, many of Tele Vue’s later signature features – the focuser, clamshell, tube design - are already here. And like all Tele Vue’s, it was made by hand in the USA. Unlike most later Tele Vues, this version comes as a complete set, with an early version of the Panoramic mount as well as the usual accessories (all with matching brass features).

I love classic scopes and have tested a few, but optically classic scopes can be a mixed bag. Some (like the Swift I tested a few years back) are top notch in every way. More often, classic scopes evoke powerful nostalgia, but don’t really work that well. In this review, I aim to find out which of those camps the Tele Vue Renaissance is in.

At A Glance

Telescope

Tele Vue Renaissance

Aperture

100mm

Focal Length

550mm

Focal Ratio

F5.5

Length

32”

Weight

~5 Kg

 Data from Tele Vue/Ed’ Ting/Me

What’s in the Box?

The Renaissance came complete with a hard case, mount and tripod, 2” diagonal and a 26mm Plossl eyepiece (and instructions).

Design and Build

The Renaissance went through several iterations over its thirty year life, eventually morphing into a brass version of the doublet TV-102. However, older models were all a quadruplet Petzval design, like a Tele Vue Genesis but with brass bits.

Although this Renaissance was made at Tele Vue’s earliest site at Pearl River, NY (they later moved to Suffern and then Chester), there was an even earlier model, with a different style of focuser body (less like modern Tele Vues). Fellow reviewer Ed’ Ting reported that these earliest Renaissances performed a little worse than this one (Ed’s review is nineteen years old now, but still well-worth seeking out). Still, this version lacks the sliding dew-shield and fluorite element in the reducer that benefited later versions.

This particular Renaissance version is unusual in that it was produced to commemorate the much-hyped (though utterly anticlimactic) return of Halley’s Comet in 1986. It has a brass plate on the focuser saying so.

The Renaissance is, as it appears in the pics, a beautiful thing with all those matching brass components. Tele Vues from this period have a friendly, less serious feel than their later imaging-oriented products. The (typewritten) instructions talk about wonder, majesty and thrills, advising:

“The Renaissance, like the era for which it was named, should be used for exploring … anything and everything”.

Optics

Like the TV Genesis, the Renaissance is a Petzval. This means it has four glass elements in two groups – an air-spaced 100mm doublet up front and a cemented doublet reducer/flattener at the back (actually mounted in the front of the focuser tube). The front doublet has a long focal length (probably natively about ~F11) which the Petzval lens reduces by about half (down to a fast 550mm, F5.5, in the Renaissance). This design reduces the OTA length as well, but not by quite as much.

There is some misunderstanding about Petzvals. The four-element design allows greater freedom to correct field curvature, astigmatism and coma, so the Renaissance should have a flat field with stars in focus and pin-point to the edge. But it doesn’t correct for chromatic aberration: the false colour level is much the same as it would be with the front doublet on its own. So, in this case, the false colour is similar to what you might expect with an ~F11 achromatic doublet, i.e. decent but not perfect. The modern NP-101 has a similar design but is a proper apochromat because it has an F11 ED doublet up front which gives very good false colour correction (even an F9 ED doublet, like TV’s own TV-102, is a well-corrected scope).

The punch line to this is that the Renaissance, like the Genesis, performs at best like a semi-apo, albeit a fast one that combines a flat field with the reduced false colour of a slower objective.

In these earlier models, neither the doublet nor the Petzval lens contain fluorite or ED glass. Later ones, termed ‘SDF’, had SD glass in the objective (and fluorite in the reducer) and so much better correction. The Petzval lens in the SDF was also a bit larger (purportedly 66mm instead of 60mm) for better coverage. The lenses and cell appear similar to modern Tele Vues. The objective is multi coated, but perhaps not quite to modern Tele Vue standards.

Optical design from the renaissance booklet.

Tube

The tube is solid brass. That means it looks classy, but is heavy and acquires a dull patina over time. It does show up finger marks. To keep it shiny you need to polish it regularly with something like Brasso and then car wax (it hasn’t been lacquered, which in a scope of this age is a good thing).

Like all Tele Vues, the lens is held in a permanently collimated cell, nudged by hand into alignment on an optical bench and then connected to the tube with blind rivets – it sounds a bit crude, but typically works very well. I once saw an (admittedly much smaller) Tele Vue refractor fall off its mount onto tarmac and it suffered no ill effects, so it’s a robust approach.

Unlike modern TVs, there is no sliding dew-shield, just a very short fixed one. The lens is protected by a screw-fit metal cap, again familiar to all owners of TV scopes (except for the TV-60).

As with all Tele Vues, the tube has no baffles, but is lined with flocking paper that may or may not be black-painted sandpaper – it looks like it. I have seen this paper come loose, but in this case, it’s still in perfect condition.

Focuser

Despite being over thirty, this Renaissance shares many features with recent Tele Vues, including the focuser, which has a cast and machined body and a 2” rack-and-pinion drawtube. The focuser is single speed, like other Tele Vues until about a decade ago, but for the Renaissance the drawtube and focuser wheels are made from brass to match the tube (as are the set screws on the visual back and diagonal too) instead of chrome with ‘mag’ wheels.

Mounting

The Renaissance has the black anodised clamshell that you find with all other Tele Vue scopes (apart from the largest NP-127). The base of the clamshell has two ¼-20 threads spaced to match fit any Tele Vue mount, along with a single central one. Studs thread into these holes and are secured to the swing cradle of the mount by black Bakelite knobs. It’s all familiar TV and very classy. The only thing this clamshell lacks is the finder dovetail you get with later examples.

The mount is an attractive thing. It looks like a modern Tele Vue mount, except with brass fittings. Actually, it’s a bit different – an early version of Tele Vue’s lighter Panoramic mount. The swing cradle is formed from one curved piece, not bolted together; and the bearings are smaller. The tripod lacks a tray, having a spreader at the bottom made of sheet metal instead. The wooden parts look like walnut, but may be stained ash.

The tripod is less solid than a modern Tele Vue (perhaps due to the lack of a bracing tray): it is all too easy to get it out of shape when moving it. Consequently, compared to a Gibraltar (or even a modern TV Panoramic), this mount is a bit more wobbly. All in all, the mount (surprisingly) is the least functional part of this classic scope rig and the scope would perform even better on a rock-solid (sorry) Gibraltar.

Clamshell has three ¼-20 threads. The outer two hold the studs that attach the Renaissance to the Panoramic mount.

Accessories

The Renaissance comes with a brown hard case, lined with red velvet. The 2” mirror diagonal and clamshell have unique matching brass thumb screws and so are part of the ‘set’. Only one eyepiece was supplied, a 26mm Plossl that is an absolute beauty.

In Use – Daytime

Daytime views seem outstanding at first, wide and flat and detailed. But look at high branches or a bird in silhouette and there is quite a lot of proper, old-fashioned false colour: apple green and purple. Now that so many spotting scopes and binoculars use ED glass to reduce false colour, this is a reminder of the way things once were. Even so, the Renaissance is sharper and brighter than most terrestrial scopes, even today.

The Renaissance was intended for daytime photography. Mine came with a glossy promo’ flier detailing its photographic potential. Meanwhile, the instruction leaflet calls it, “… a fast 550mm F5.5 telephoto camera lens for 35mm single lens reflex cameras.”

This turns out to be true: the Renaissance gives excellent, sharp photos. The false colour that limits it for deep-sky astrophotography isn’t a problem at all.

For terrestrial photography, the Renaissance makes a surprisingly sharp telephoto with minimal vignetting (APS-C at least).

In Use – Astrophotography

The wide flat field and fast F-ratio would make for a great astrograph … and they do in the otherwise similar NP-101.

The Renaissance (how I prefer typing that name to ‘NP-101’) was designed for 35mm film, so on APS-C coverage is unusually good for a Petzval and flatness is excellent too. But the Renaissance shows what I mean when I talk about ‘violet bloat’. Almost every blue or white (O-A) star has a bright blue halo. The result is genuinely attractive, but not authentic.

The central region of Auriga with M36 is filled with sharp stars, but there is too much violet bloat for anything but casual imaging.

Despite the small image scale, snaps of the Moon come out very sharp indeed. Zoom right in to the image of a Moon/Jupiter conjunction below and you can see Jupiter’s equatorial belts and a hint of GRS – evidence of very good optics.

The Renaissance makes casual deep sky snaps easy and rewarding and takes super-sharp photos of the Moon. But it suffers too much chromatic aberration for ‘serious’ imaging.

Moon and Jupiter: conjunction imaged through Renaissance.

In Use – The Night Sky

General Observing Notes

The deep sky view is a fraction less sparkly than an NP-101, blame the old-fashioned coatings.

False colour isn’t a problem for visual deep sky, but is more so for the Moon, planets and imaging. This is one big reason why this isn’t a budget NP-101 (or other modern Petzval - Takahashi FSQ etc).

With Tele Vue eyepieces the field is very flat, but some others struggle with the steep F5.5 light cone. Though the field is flat, there is some distortion of off-axis stars by coma and/or astigmatism you don’t get with a later TV petzval.

The focuser is decent, but has a bit of image shift at high power (probably due to age and wear). It’s not as buttery and precise as later single-speed TV focusers that have the ‘mag wheels’. Depending on your eyes, there is just enough (or just too little) outward travel to bring a 55mm Plossl to focus.

These earlier clamshells don’t have a finder mount and there is no other obvious way to mount a finder. But with a 550mm focal length giving a maximum field of 4.8° you just need a low power 2” eyepiece to find stuff.

The dewshield is very short and affords little protection – against dew, but also stray light (and knocks). Later versions have a sliding dew shield like recent Tele Vues.

I think the brass tube makes the Renaissance a bit heavier than the otherwise similar Genesis model, but it is still easy to move about setup on its mount, ideal for quick looks.

Cool Down

Like other Tele Vue quadruplets I have tested, cool down is fast and benign, again making for a great quick-look scope.

Star Test

The star test looks good with near identical rings either side of focus. Some say Petzvals can go out of collimation, but not this one. In fact, the only bad one I’ve ever seen was an NP-127 and that may have been the result of a knock during shipping (and Tele Vue fixed it for free anyway).

Basic optical quality is very good, but in focus star images are a little less pinpoint than the best modern scopes, due to the field-flattener.

The Moon

At 21x with the standard 26mm TV smooth-top Plossl, a gibbous Moon in a twilit sky looks wonderful – sharp and detailed and full of contrast; there’s just a pale band of violet around the limb to distinguish this from a modern apochromat.

By 37x with a 15mm Panoptic, that rim of false colour is a feature of the view, but the Moon is still sharp and starting to show some of my favourite features, from Alphonsus and Arzachel to Plato on the terminator.

With a 5mm Nagler giving 110x, the Moon fills the view. Sharpness and detail are still excellent, typical of any quality 4”, but whereas an NP-101 would be all whites and greys and black space, that rim of purple is prominent. Overall, it’s still a great view, though. Smaller craters and rilles are on view that you’d struggle to see in a 3” scope of any quality. At this power the mount seems wobblier than the (apparently similar) modern TV Gibraltar.

At 157x with a 3.5mm Nagler T6, getting perfect focus is a hit and miss affair: the mount is too wobbly, the focuser too coarse. The Renaissance wasn’t designed for this kind of magnification, but still the Moon is sharp and full of detail once you manage to tweak it in. I noted craterlets in Plato and Gassendi and lots of rilles round about. However, the limb of the Moon is now surrounded by a border of bright purple; the Lunar highlands have a purple wash too.

Venus

At 110x with a 5mm Nagler, Venus shows a perfectly clean, brilliant crescent. There is none of the softness, stray light, ghosts, spikes or problems getting focus which Venus sometimes causes. But this is where the semi-apo in the Renaissance shows, because surrounding that crescent is a bright halo of Imperial Purple.

Mars

Mars at only 4” showed a crisp tiny ochre bauble at 110x with a 5mm Nagler, with just a trace of stray red light around. Upping the power to 157x with a 3.5mm Nagler it remained crisp, but at these powers the mount and focuser are the main issues anyway.

Jupiter

At 157x with a 3.5mm Nagler T6 Jupiter shows significant cloud belt structure, with the GRS almost on the Meridian and a dark storm or two visible and a hint of banding in the polar hoods. It’s a sharp view, but with a slightly yellowish cast and a distinct purple border around the planet. It’s an enjoyable view, but not a match for a modern 4” APO.

Deep Sky

Tele Vue’s Petzvals are always perfect for deep sky and the Renaissance, old though it may be, is no exception. As usual, the 13mm Ethos is my favourite deep sky eyepiece, giving 42x.

The Pleiades are super-sparkly diamonds on velvet. The clusters (M36-38) in Auriga populous and lovely with their surroundings full of stars to the field stop. Smaller nebulae like the Ring in Lyra and globular clusters like M15 stand out well from the background, but are most notable for the context that the wide, flat field gives – surrounding them with sharp, pin-point star fields.

Viewing deep sky like this, with one widefield eyepiece, no finder and just pushing the scope around is addictively simple, a bit like binoculars: a real antidote to your filter wheel, cooled camera, bias frame acquisition and whirring robot mount.

A scope like this isn’t ideal for doubles, but split Epsilon-Lyrae in mediocre seeing.

Summary

The Renaissance still looks fantastic and overall performance is much, much better than most classic scopes, especially if visual deep sky is your thing. Pop in an Ethos or a Nagler and the deep sky views give a taste of that immersive feel Tele Vue are famous for.

Don’t think the Renaissance won’t do high powers on the Moon and planets, though – it will, sharp up to 100x and beyond. But the Moon has a halo of purple at higher powers, as does Venus. Daytime views are excellent too – bright and wide and detailed - but high contrast areas reveal some false colour. The Renaissance gives great views, but it is not a cut-price NP-101: it is at best a semi-apo.

Despite the flattener, off-axis aberrations are slightly worse than recent Petzvals too, though the field is flat for imaging and coverage excellent on APS-C. Deep-sky images reveal bright violet bloating on blue-white stars. However, the Renaissance does work very well for casual imaging, as a terrestrial telephoto lens or for snaps of the Moon.

The other area in which the Renaissance falls behind modern Tele Vue’s is the mount: it looks a lot like a Gibraltar, but lacks the tray and is less solid and stable.

The Tele Vue Renaissance is a wonderful ‘classic’ scope and is highly recommended. Visually, it does everything well, albeit with a bit of false colour. It is fast and has a flat field, so you can have fun with terrestrial photography and astrophotography too, but there’s too much false colour for ‘serious’ imaging.

Roger Vine 2018

 

 

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