This auction is for a 1988 Celestron (Vixen of Japan) 1.25-inch Plossl Ocular 45mm; also known more widely as the 45mm Silvertop. It will come with BOTH original dust caps.
These Vixen of Japan-released (Ah, some with the Vixen mark still had their glass coming from other Japanese firms) oculars were some of the very best designs of their kind on the market ever. The funny thing is though, we experienced collectors all recite these as "Silvertops" when referring to the silver satin plossls and matching 2x barlow. But in truth, and depending on the year in the Celestron catalogs, these are "Deluxe Plossls" and a "Deluxe Barlow". The term "Silvertop" was a name us customers attached to them over the years due to their very brilliant, silver appearance. By the mid-1990s, the name stuck for good.
What is very interesting about the Deluxe Plossls is that when you received them with their orange boxes (oldest models had cardboard boxes, not pressboard) and plexiglass "pill" capsules, they are called "Plossl Oculars". Never does the box actually state "Deluxe" on the plossl model labels. So, we can call the "Silvertops" either Plossl Oculars or Deluxe Plossls and remain correct-to-code.
When viewing the label on the original box (should you have one), it should read:
CELESTRON
PLOSSL OCULAR
11/4" 45mm
In order to align the bidder and future seller properly; when we are speaking of "Silvertops", us collectors are specifically referring to the all-silver satin-bodied Celestron plossls with "((V)) or (V) JAPAN" on the chrome barrel. The characters on the silver bodies are always etched and always orange.
If the top of the eyepiece has a black ring and/or the characters are no longer etched, but a laminated, red film print, even though many of these are also from Vixen of Japan, they are not part of the "Silvertop" group.... Though I personally still include the rare 50mm 2-inch plossl that Vixen sourced Celestron for their heavily bells and whistles-modeled Compustar 8.
Barrel size: 1.25-inches
Design: 4-element plossl (2)(2) concave-convex doublet configuration
Optics: multi-coated
Field of view: 33 degrees
Eye relief: 18mm
Exit aperture: 27.7mm
Threaded for filters: yes
Materials: milled aluminum and brass, optical glass
Weight: 4.6 ounces
The Plossl Ocular Silvertop first came about in spring of 1984 (the same time when the orange Celestars went to black gloss) and was made available in exactly (5) focal lengths: 45mm, 36mm, 26mm, 17mm, and 10mm. Featuring only fully coated optics at the time, these always came in a thick, orange, 2-piece cardboard box with a small white label. This was before mpn codes were commonplace and so codes never appear on the labels.
Depending on the size (50mm and 45mm excluded), the eyepiece would be stored inside a clear plexiglass cylinder with a white nylon plug lid, and with an orange center; overtime called the "pill bottle" or "cyclops". When the next generation came about near 1987, additional focal lengths were added to the family. Another big change was that the optics were now multi-coated. And a final, lesser-observed change; the boxes, though still orange and with the white label, were now a thinner 1-piece pressboard.
If you are looking to complete the entire set of "Silvertops", it can definitely be a difficult, yet highly rewarding experience. In some cases, the only way to get certain models was to get it with the telescope. In other cases, not all years offered all the models at the same time. By 1989 only (5) focal lengths were available. By late 1990, only (3). By January 1991, they were gone forever with the exception of the 22mm and the Ultima line took center stage until eventually alongside their less complicated plossl brethren; the "Halloween Plossls" of early spring of 1994.
It should be side noted that in the middle of 1990 and into 1995, Celestron and Vixen were still tossing around the Silvertop concept (so to speak) in that some of these focal lengths in "Silvertop" fashion were still being included with carried-over telescope models. These would be the silver body, but with the black ring on top. The characters were not etched, but a printed laminate logo; the ones with a Roman-like "V" stamped in the center were generally direct-from-Vixen. These were multi-coated just as was the previous generation. However, the optical configuration was now (cemented plano-convex)(cemented plano-convex) instead of the higher resolution capable (cemented concave-convex)(cemented concave-convex) format.
I have completed the task of acquiring a complete set and it took me 9 years. Below is the to-code inclusive set as it would have appeared from Celestron. Note that not all Silvertops were separate purchasable items:
50mm (only with the Compustar 8)
45mm
36mm (C14 1987-1989 only)
30mm (JAPAN only with the C11 and C14 Astro and exceptionally rare and valuable)
30mm (Taiwan offered as a separate purchase for a very limited time)
26mm (NJ JAPAN; a rare, corporate mistake of NJ supplying outside of Tele Vue)
26mm (widely inclusive until 1991)
22mm (S-55F refractor and 2nd gen RFA kit)
17mm
15mm
10mm
7.5mm
2x Deluxe Barlow
Aside from the 50mm Silvertop, which was a 2-inch barrel, ALL other models are parfocal.
Like most of the Silvertop family, the 45mm was not inclusive to any telescope setup or accessory kit during its entire run. Despite it never having gaps in availability in the catalogs, its popularity was not strong because these were expensive plossls in their day AND their field of view, at 33 degrees, was looked down on by many backyard observers. Back then the Ultima 42mm had yet to debut and nearly all other competing plossls at the time never crossed the 40mm focal length before becoming a 2-inch ocular. Those 40mm plossls were yielding 38 to 42 degrees field of view, so the 45mm Plossl Ocular had a hard sale.
The largest focal length I ever knew in a 1.25-inch barrel was the elusive Criterion 50mm Hastings and equally rare 50mm Ramsden (none of you will likely ever see one in person), and these eyepieces gave way-in-the-backseat, narrow views of 22 to 25 degrees!
At 45mm, this eyepiece is going to be VERY low power and most of your observing subjects will be Orion's Sword region, the Double Cluster, M24 star cloud, M31, The Pleiades, The Beehive, the Moon, and Jupiter on lesser-seeing nights. For those in the Southern Hemisphere, this would be fantastic for the Magellanic Clouds, Omega Centauri, 47 Tucanae, The Jewel Box, The Coal Sack, and NGC3195. Eye relief will be huge and so those needing to keep their eye wear on during observing should have no issues achieving the full field of view.
On a lasting note, wonderful as this vintage plossl is, when pushing very, very low power in a schmidt or maksutov cassegrain system, you run the risk of projecting the central obstruction; generally, the shorter the focal ratio on the cassegrain, the more prevalent the central obstruction becomes at low power. If using this in, say your Meade 8-inch LX200 optical tube, you will see a dark, donut-shaped region in the meniscus. It is an optical effect similar to the mesh screen on your window. If you press your face up to the screen, you see passed the obstruction in front of your eyes. But as you back away from the screen, the background is darkened and the obstruction becomes noticeably amplified.
Now with reflectors, particularly longer focal ratio models with smaller secondary mirrors, this is not NEARLY as noticed as in the cassegrains.
In refractors, this eyepiece (all Silvertop plossls in this case) shows its true flat field design capability. Pinpoint sharpness across the visual plane with no loss of contrast.
This auction ad was completely, organically written by Veradale Mobile Observatory, not an A.I. software device; an actual honest-to-goodness, real human with over 20 years experience with now over 1000 telescopes made from today and all the way back to 1948.
Packed with great care.