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Tele Vue 24mm Panoptic

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To say that my first experience with a wide-angle eyepiece was inspiring would be an understatement. Having previously believed that Plossls were panoramic, I was blown away by an expansive (albeit rather poorly corrected) 65 degree field, and instantly transformed into a wide-angle addict. As a long-time lover of open clusters, I felt that wide-angle eyepieces allowed me to travel to them, increasing the magnification without cutting off any of the stars. I felt as though I were among the stars, and the experience to this day makes my body feel lighter. Simply put, I crave immersion. Years later, my eyepiece collection contains a healthy number of such oculars, but for a long time I opted to save money, and upgraded through generations of inexpensive designs with smudgy edges from field curvature and abysmal lateral colour. Leafing through the pages of Sky & Telescope, I would dream of owning a fleet of Tele Vue Nagler eyepieces. That dream seemed a long way off, and frankly it still does! But Tele Vue have also attempted to bring us Nagler-like performance at a more attractive price, albeit it over a smaller field. They’re called Panoptics, and in the 1.25” format, the 24mm is king. The question is, how does it measure up?

Essentially, the 24mm Panoptic takes the true field of a 32mm Plossl and puts you, the observer, deeper into it. That’s because it has the same 27mm field stop diameter – the largest possible in a 1.25” (31.7mm) format barrel. The increased magnification, according to Tele Vue, results in a darker sky background for better contrast, and improves the visibility of finer details in extended objects. There’s nothing controversial about the theory here, and all the while, the apparent field expands to a generous 68 degrees. This value is common for wide-angle eyepieces, because it corresponds very well with the acceptably sharp portion of the human eye’s vision span. So without moving your eye, you can enjoy the whole field with the edge resting close to what we generally consider to be the mid-periphery of our vision. The result? Immersion. You’re closer to the field, and the sensation shifts from looking down a well to standing very close to a porthole on your own private spaceship. Naturally, the sacrifice is eye relief, so comfort will be a crucial factor in evaluating this eyepiece.

From the many discussions I’ve had about the 24mm Panoptic over the years, it feels as though it’s been around forever. Not so; it was actually brought to market in 2002, making it the second youngest member of the Panoptic family (after the 41mm) which was itself introduced 10 years prior to that. It just feels like a classic, and that must be a testament to its design and execution. The astronomical community has thoroughly embraced it and some have even called it the finest 1.25” wide-angle eyepiece available – fending off all competitors for overall image quality, field-of-view and value. Also, fans of binoviewers have often lauded the 24mm Panoptic as the premier option for low power. Quite a reputation. Optics aside, I suspect that the mechanical construction has also contributed to its meteoric  success.

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On the outside, the 24mm Panoptic is every bit the high-performance ocular it claims to be. The fit and finish is absolutely sublime – not unusual for Tele Vue – and it bears emphasising that the eyepiece handles beautifully. All 230 grammes are solidly housed and comfortably lifted thanks to its large grip. The machining on the barrel is among the best I’ve ever seen, with shallower tapering at the front side of the recess than seen on, say, the Type 6 Nagler. This provides additional support in compression clamps, and I’m happy to report that it’s entirely snag-free. Inside, Tele Vue have cleverly opted not to blacken the first few millimetres of the filter thread, so there’s nothing to come away and potentially settle on the field lens or filter. Additionally, the thread is mechanically perfect, accepting a variety of manufacturer’s filters without complaint. Granted, it does look rather like a mushroom, but the housing is just right, and there’s more to its shape than meets the eye. Rarely mentioned is the ‘volcano top’ style profile of the upper third of the eyepiece, which leaves ample room for the observer’s nose when tackling the 15mm of eye-relief. In my opinion, this alone is a tremendous selling point in favour of 24mm Panoptic, and I can see why it’s so popular for use with binoviewers.

My only complaint relates to the eyecup. It’s comfortable and easy to fold, but it’s a diabolical magnet for bits of crud. Whether it’s dust, tiny flecks of hair or something else, it just seems to collect and is very difficult to clean off without entirely removing and rinsing the thing. Fortunately this is easy to do, but within minutes of handling it’ll all be undone again! I should note that this is a common problem with eyecups across the board, but there’s room for improvement here. That is a small gripe, and to conclude, the design is first class; the attention to detail exceptional.

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Does this trend continue with the most important facet of all: the optics? Put simply, yes. But simply doesn’t cut it here – we need to take a detailed look. Securing the eyepiece at the back of my 80mm F/7.5 refractor, I slewed to the first quarter moon, focused down, and was met with a staggeringly high-contrast image. At this low power (25x) I surveyed a full 2.7 degrees of sky, and even without tracking I scarcely noticed the stars entering and exiting the field until a few minutes had passed. Eventually I took it upon myself to scrutinise a star near the edge as it moved off, looking for field curvature. There was none to speak of. The many field stars (and there were many, even in the moon glow thanks to the Panoptic’s deep contrast) appeared razor sharp to the field stop. To convince myself I positioned Luna at various points in the field and monitored the focus of the smaller, visible features. It looked absolutely phenomenal, notably better than the Vixen 22mm LVW, and substantially better than the Baader 24mm Hyperion – two eyepieces I’ve used recently in the same telescope. A very good start.

During this initial test, I did become aware of the dreaded pincushion distortion known to affect the Panoptic range. I do feel, however, that the severity of this effect has been greatly overstated in most reviews. Negative distortion is present when panning over the Moon or a busy star field, but it’s there by design, unmitigated to balance the Panoptic’s 6-element design for a sharp, flat field, even in fast telescopes. It’s actually somewhat less intrusive than in its competitors, so I’m not convinced that the criticism is fair, particularly when measuring the 24mm Panoptic’s pricing against its big brother – the 22mm Nagler. The pincushion is virtually imperceptible on untracked star fields, and one would have to be a real encyclopaedia of stellar cartography to notice it whilst tracking. As for reports of “sea sickness” when panning quickly, I can’t personally make comment as I’ve never been susceptible to any kind of vision distortion or motion sickness.

Granted, geometrically critical observations cannot be trusted if made through the 24mm Panoptic, but this eyepiece is about the visual experience, and that remains untainted by the distortion. On deep-sky objects such as M42, M45 and M31, the views were superb and highly memorable. Only later in the test did I realise I’d had no trouble with the eye-relief at all. From experience, I would put it at slightly less than the stated 15mm to get the full effect, but it’s still perfectly comfortable. I should note that the 24mm Panoptic is compatible with Tele Vue’s astigmatism-correcting Dioptrix lenses, though you will need an adapter. Viewing comfort – perhaps the biggest hurdle faced by this eyepiece – is superb. It’s so good as to be a non-issue, which is exactly the way it should be. Nothing prevents you from enjoying the sharp, high-contrast porthole on your spacecraft. The field stop melts into the blurriness of your peripheral vision, but should you choose to look you’ll find it to be a pleasing knife-edge, with only the thinnest film of lateral colour present. Even the extremities of the field exhibit virtually zero chromatic aberration, and to top things off, scatter is nowhere in evidence. The sheer image fidelity across the entire field is as good as almost any eyepiece, with fewer elements, on-axis. Only the finest orthoscopics, monocentrics, and Tele Vue’s own newer designs can best it.

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The design has been figured for a wide range of focal lengths. I found little to no compromise in image quality from F/10 down to F/4 in a full six different telescopes, and continued to compare it with my Tele Vue 32mm Plossl, of which I am very fond. In each case, I discovered that I preferred the view in the Panoptic, despite the tighter eye-relief. Perhaps a spectacle wearer might disagree on that point, but it would be hard to disagree with the benefits of being carried deeper into the stars without any other compromise worth noting.

It’s clear to me that Tele Vue have spared no effort in crafting a brilliant eyepiece with the 24mm Panoptic. I put it to the reader that anyone could improve their collection with one. Its versatility and finely tuned field render it a genuine upgrade to any 32mm or 40mm Plossl, as It takes you into the sky whilst delivering the promised contrast and, some pincushion aside, delivers beautifully corrected views in a wide range of instruments. If you purchase this to replace a stock 25mm eyepiece, you’ll struggle to explain to others the unquantifiably tremendous improvement to the viewing experience. If you’re okay with the eye-relief (and the asking price) the 24mm Panoptic deserves to be your low power 1.25” eyepiece. Highly commended.