Pentax Binocular Lines in 2023 – A Scavenger Hunt

I wrote about some of the better Pentax binocular lines about five years ago in this review. I don’t remember now how difficult it was to gather that information, but I can tell you it was more of a scavenger hunt than a picnic to glean what I could for this current article that will cover all the Pentax binocular lines available in 2023.

I will rant a bit because the Pentax site is…well, not exactly messy, but certainly not visitor-friendly. Some of the information about a given set of binoculars you can get on a product page, but some of it is only on the related store page. A page may tell you the cost of both the 8×42 and the 10×42 models in one of the Pentax binocular lines, but then it only gives you specifications for the 8×42.

I could go on, but that’s not why you’re here. In fact, I’m here to give you all the pertinent information in one place so you don’t have to scavenge like I did. That said, I’m not going to give you every tiny detail here – after all, there are some specs I never did find. And I won’t be rehashing all the info about the Pentax binoculars lines I covered five years ago. For the Papilio and ZD lines, click the link in the first paragraph above.

What I have compiled for you here is the data for these Pentax binoculars lines.

• U series
• Jupiter
• S series
• A series

Plus, I’ll cover the unique VD 4×20 WP, a 3-in-1 binocular / monocular / telescope device.

Is There Rhyme or Reason to the Pentax Naming Convention?

Before I delve into those four lines, I’ll mention a few conventions that Pentax uses throughout. As to whether there’s really a rhyme or reason to this, you be the judge. Personally, I don’t understand why, with the exception of Jupiter and Papilio, Pentax only uses single letters (actually, letter pairs, as you’ll see) to name their lines. For that matter, why do two lines not use such letters? Also, I don’t know why they picked the letters they did – U, S, A, and Z.

Each of the lettered lines begins with the given letter for the series followed by either a “D” (for roof) or a “P” (for Porro). Why didn’t they use “R” for roof? I dunno. Maybe “roof” translates into a word starting with “d” in another language.

Update: I didn’t realize how right I was. “Dachkantgläser” is German for “Roof glasses”, so UD, for example, now makes perfect sense. Of course, this raises the question as to why, if my interpretation is correct, a Japanese company is using German terminology.

The model name then normally shows the size (like 8×42) of the binoculars. And finally, there may be a “WP” (for waterproof) or an “ED” (for ED glass). If there’s nothing following the size numbers, I think it’s safe to assume that the binoculars are not waterproof and do not use ED glass.

I think that all the WP models have nitrogen purged tubes. I’m as confident about that as I am about all models having fully multi-coated lenses. Note: My confidence level is not high for either.

I could only find a handful of models that definitely use BaK4 prisms, but that doesn’t mean much. The lack of any reference at all to the quality of the prisms was painfully obvious. I don’t take this to mean that the binos use something less than BaK4. I’m just not willing to assume anything in either direction on this.

Now on to the individual lines.

Pentax U Series Binoculars

Generally speaking, of all the Pentax binoculars lines, the U series is the least expensive, ranging from about $50 to $130 (MSRP). These are compact optics that have a bit of flair; i.e., color built into them. You can get the UD 9×21 and 10×21 in basic black or navy, green, pink, or orange. As you can see from the pictures of the orange model below, the colorful models are actually two-tone.

The UP 8×21 and 10×21 come in black, navy, or pink. You can get the UP 8-16×21 zoom binoculars in black, brown, or green.

The UP models also come in 8×25 and 10×25 sizes – both as waterproof (WP) and standard types. The WP models weigh just a bit more (at 12.3 ounces) than their counterparts.

Pentax Jupiter Series Binoculars

I suppose one reason Pentax went with “Jupiter” for this line is that these are larger binoculars intended for skygazing. But they might just as well have used “H” for the “Heavens” line, right?

The Jupiter line – sizes 8×40, 10×50, 12×50, and 16×50 – retails just above and below $100. These are Porro tubes that apparently are not waterproof. These weigh in the vicinity of 30 ounces.

Pentax S Series Binoculars

The Pentax S series is probably the line with the widest range of style and pricing. A pair in this line can cost you anywhere from about $100 for the most basic to about $400 for the best with ED glass.

The SP 8×40, 10×50, and 12×50 sizes come both with and without waterproofing. There is also a basic SP 16×50 and an SP 20×60 WP (shown below).

The SD models are at the top of this line. All are waterproof. The SD WP 8×42, 9×42, and 10×42 also have special coating that repels liquids and dust. The SD ED models – 7×42 and 10×42 – are the only ones outside the Z Series and the top of the A Series to have ED glass.

Pentax A Series Binoculars

The A Series feels like a mish-mash of sizes and styles. Here is a list of what is available.

So, they’re all at least waterproof, and the best have ED glass. The smallest weigh about 16 ounces; the largest are about 22 ounces.

Since the AD ED models are a little smaller than the SD EDs, they cost a little less. The same is true when you compare the SD EDs to the ZD EDs.

Model	Size	~Cost
AD ED	7×32	$330
AD ED	10×32	$350
SD ED	7×42	$380
SD ED	10×42	$400
ZD ED	8×43	$700
ZD ED	10×43	$880

Pentax VD 4×20 WP 3-in-1 Device

For the Pentax VD 4×20 WP, a picture is definitely worth a thousand words.

A short video might be worth at least as much.

I have questions (perhaps problems) with the VD 4×20.

As a pair of binoculars, it doesn’t magnify very much – only 4x. Even the cheapest binoculars normally magnify 7x or 8x. The same is true when you (and a friend) use these as monoculars – still only 4x. The objective lens size isn’t great (literally) either – only 20mm.

Apparently (as shown in the video), you can just pull the tubes apart to create the monoculars. I wonder how hard it is to put them back together properly. And how many times can you do this before something breaks?

When you put them together end to end to make the telescope, it’s still only magnifying 16x. And that setup has to allow light to pass through two “objectives” and two “eyepieces”. I can’t imagine getting a very bright image through all that.

All this makes them feel more like a toy than a tool.

However, this is a toy that costs you in the neighborhood of $250. Would you spend that much for this kind of “toy”?

I think this was a bit of an experiment on the part of Pentax. It cost them plenty to make, so they had to charge the price they do. They didn’t want to take a change on a larger pair because it may not have worked well and would have cost proportionally more. Notice that no one else is apparently making a gadget like this. Even Pentax has only made this one model.

All that said, if you want to try them out, be my guest.

In any case, there you have all that’s available in 2023 in the form of Pentax binoculars. If you didn’t find anything you like here, maybe try the Athlon lines next.