Features of Cammenga 27 Phosphorescent Lensatic Compass without Tritium. SC Some compasses are set up differently. Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. Price Paid: Around $70, Reviewed by $71.89 . They told me it would cost $60 to replace the lens. Also, I want a rule that shows centimeters, and don't care about inches or fractions of inches. I just bought the tritium compass about one month ago, glad I did. The two types of photoluminescence familiar to most of us are fluorescence and phosphorescence. The lensatic compass is used by those in the U.S. Armed Forces. First, off it was like coming home again. It is a bit heaver than you average compass but it worth the extra weight for a piece of mind. any other answers are just folks avoiding cognitive dissonance. The sighting lens recently fell out, however. But that's a story for later). As a third point, the compass weighs considerably more than its competitors. Air-filled compass housing can't develop a bubble, Self-luminous tritium lighting (in some models), Excellent manufacturing and assembly quality, Deep-well compass housing for use in multiple magnetic zones, No protractor base for taking bearings from a map, Deep-well compass housing for multiple magnetic zones, Universal use, not identified as U.S. gear. How does radium paint behave under a black light/UV flashlight? With each compass, you carry the added assurance of Tritium-based, self-powered lighting that needs no recharging. To put it simply: When it comes to performance and accuracy, Cammenga leaves all other compasses behind. Despite the name, these transitions still happen, but they're statistically unlikely and so the trapped light leaks out much more slowly than in fluorescent materials. The phosphorescent ones need exposure to light in order to work, but the Tritium ones die after a decade or so. Tritium radioluminescence is the use of gaseous tritium, a radioactive isotope of hydrogen, to create visible light.Tritium emits electrons through beta decay and, when they interact with a phosphor material, light is emitted through the process of phosphorescence.The overall process of using a radioactive material to excite a phosphor and ultimately generate light is called radioluminescence. Choosing the best compass for you depends on what you want to use it for. *Must have a registered ARFCOM account to win. Theyve been to battlefields all over the world. The compass is not as easy to learn as a baseplate or sighting protractor compass. data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAKAAAAB4CAYAAAB1ovlvAAAAAXNSR0IArs4c6QAAAw5JREFUeF7t181pWwEUhNFnF+MK1IjXrsJtWVu7HbsNa6VAICGb/EwYPCCOtrrci8774KG76 . +1, it will be fine for a long time. Clipping is a handy way to collect important slides you want to go back to later. April 22, 2009. Some are day / night, some not so much. I'm not sure how it happened. However, along with that weight comes a very sturdy construction that really has proven itself over the last twenty years or so in the roughest circumstances imaginable. Free shipping. ? The GI version has Tritium (glow) markers. Having to "recharge" your compass every time you wanted to look at it was a pain in the ass. Battle tested through rigorous shock, water, sand proof, and functional from -50 F to +150 F. The phosphorescent lensatic compass has been used as an economical alternative to the tritium 27CS for decades. Outdoor Hub, LLC (d/b/a Carbon Media Group), 30800 Telegraph Rd, Suite 1921, Bingham Farms, MI 48025 USA. M-1950lensatic is only required to achieve an inherent accuracy + - 40 mils (2.25 degrees) from actual azimuth under milspec requirements. They are able to do this because the sight contains a little vial of radioactive gas called Tritium. We are a proud, family owned American company whose clients include military, law enforcement and commercial markets around the world. Performs flawlessly in temperatures ranging from -50 F to 150 F. Uncompromised by temperature changes due to its non-liquid filled needle housing. Eyeskey Multifunctional Military Army Aluminum Alloy Compass; 2.9 10. Overview. 2001-2023 Trailspace. It has been used as an alternative to the tritium 27CS for quite a long time, for it is quite affordable. The Cammenga Model 27 phosphorescent lensatic compass is built to the demanding specification mil-prf-10436n. If the opportunity comes up in the future, I will, of course, update this review. mountainman_270 Do the tritium compasses show up with NVG? The compass dial is in both mils and degrees, and as the military uses mils,the degree scale is given second place on the dial. I have used the milspec/issue Tritium H3 clam since 1979. Since it is filled with ordinary air, the M-1950 can and does fog over in cold weatheror from moisture andhumidity changes in tropical regions, since the interior is not purged with inert gas like your fogproof binoculars or rifle scope. Posted: 1/16/2012 1:33:21 PM EDT. Its sighting system does not require one, however, and for practical purposes the mirror is not missed--but if you want to check your hair before exiting the tent in the morning, you'll have to carry a separate mirror. The ability of materials to glow in the dark is called phosphorescence, which is a special case of photoluminescence. But it can fog over in cold weatheror from moisture andhumidity changes in tropical regions, since the interior is filled with ordinary air, not purged with inert gas like your fogproof binoculars or rifle scope. Tritium is much better. Then there is the issue of inherent accuracy. I would definitely recommend either one of these compasses to any one. Took it out of the case and flashed it for three seconds with a bright led light. Anyone have a link for a good compass to purchase? no question. Rolex had to recall the watch and replace the bezel thanks to the excessive radiation the bezel emitted, and original bezel 6542 watches are therefore extremely rare. Source: bought it new I use them both, but normally I find my base plate compass easier to use and read, making it the best compass for me. I like the locking card, the tritium dial and the maginifier. Luminous dials are a compromise. It is much more than most people need. The earth's magnetic pull wants to pull one end of the needle down. Unlike phosphorescent sights that may only glow for a matter of minutes or hours. Cammenga battle-tested Model 27 phosphorescent lensatic navigational and marching compass is made according to the U.S. Army Mil-Spec. You probable wouldn't even need a ponch. While not difficult for an experienced user, someone who is used to setting declination and forgetting it thereafter will have to be reminded occasionally to make the proper adjustment in sighting. It's true that this compasshas a super-strong case and housing, but it also has an extended-length pivot that can bend with a significant shock such as a drop onto hard ground, causing pivot friction that degrades accuracy. Sale price: $37.50. Copyright 2023 Cammenga Company, LLC. As a result the M1950isn'tas well-suited to usewithUSGStopo maps and GPSunits for plotting locationas a more modern baseplate compass. See questions and answers Customer reviews. In the northern hemisphere, it pulls the needle's north end down. Lasts about 10-12 years, then donated to scouts. The compass dial is in both mils and degrees, and as the military uses mils, the degree scale is given second place on the dial. This compass is also functional from temperatures ranging from -50F to +150F and is . Deserted http://www.cammenga.com/Tritium-Protractor-Compass-p/d3-t.htm. It can be a little more difficult to learn on. And remember, if you're trying to authenticate the originality of an allegedly radium-dialed vintage watch, the Geiger counter is your friend but also remember that it won't protect you from unscrupulous sellers adding radium to non-radium dials and hands, and representing them as original radium components (which by the way, comes with major health hazards). Kjellstrom introduced the sport of orienteering to the USA in 1946. Nuclear reactions may produce a glow. Benjamin Hirsch Michael Manzo A more minor criticism is that theM-1950 compass dialhas noprotractor feature, so you needto carry a separate protractor to take a bearing directly from the map. My 159-page, fully illustrated book is yours for the asking. Shockproof, damage-resistant design. Let's look at how radium dials work. I don't see a huge, non marine, military, or aviation use for such a compass. The model has tritium inserts and appears to be made of aluminum. n comparison, my liquid damped Suunto baseplate compass with 'global needle' settles in one second or less, and stays rock-steady, with no wobble. Item# J582. I also have a military with the tritium. I have one of each. AR15.Com reserves the right to overwrite or replace any affiliate, commercial, or monetizable links, posted by users, with our own. Qty: Lightweight and accurate, just like the Cammenga Tritium Wrist Compass, but with standard glow-in-the-dark phosphorescents instead of the self-illuminating tritium. Don't buy a compass with bubbles in the housing. Most people will waste there money if they buy a 3H. In most cases, you'll get a personalized quote in seconds and your policy kicks in immediately. In summary, the M-1950 lensatic compass in 3H configuration as made by Cammenga is a special-purpose military compass that needs a redesign to compete as a general-purpose wilderness navigation compass. I don't think this is a compass for everyone. Open the lensatic compass as shown in . They are often referred to as self-illuminated, though anymore this is a fairly redundant term. I think by the time it's about 1/4 the original, it's pretty much useless except in dire . Each "click" is 3 degrees. Tritium , I have an older usgi one, The IOR compass seems nice for $50. Fluorescent materials tend to emit absorbed energy very rapidly they'll glow as long as there's a source of light to excite the material (typically with what's described as "neon" coloration) but emission takes place over a time scale of mere nanoseconds, so they will go dark the instant a light source is removed. Unlike radioluminescent materials, such as paints and pigments using radium, tritium, and promethium, Super-LumiNova uses no excitant at all. What kind of situations are those? Reviewed by Cammenga does an excellentjob on meeting milspec standards. Professional Multifunction Military Army Metal Sighting Compass; 2.7 8. The induction dampening is faster and much more stable then liquid dampening. Uses a copper induction-damping ring that slows, settles and steadies the compass needle quickly. The fastest and most secure way to protect the watches you love. The map's UTM gridmeasures kilometers, not miles. Best overall: AOFAR AF-4074 Military Compass. Well-made, but less than ideal for non-military users. Are you experienced? Definitely worth the extra tariff. Source: bought it new Cammenga, Model 27 Compass, Olive Drab US Military Issue pouch. Also used the Pyser M-73 (degrees) Black Liquid Prismatic Compass and MILS a lot in locations not friendly to U.S. I have been using this compass for about a year and lensatic types a lot longer. Tritium paint for watch dials and hands will lose its ability to photoluminesce over time, although as with promethium, degradation of the phosphor will take place more slowly, as tritium is a much weaker radiation source. One other thing I like about the Suunto M-3G is that it has a "global" needle. The subject is one of the greatest interest to collectors and yet, there is still widespread misunderstanding of how luminous materials actually work. He didn't notice it missing of course, but it shouldn't have been a big deal. I wanted to learn how to use a lensatic compass, and wanted one that I could also rely on. The tritium sighting is a great option for low light and the occasional emergency night hike, and should be available onother compass models here in the states (outside North America, anyone can buya Silva of Sweden4b or 54bExpedition militarycompass with beta, or tritiumlighting). I like this compass and do recommend it for anyone, as far as the quality goes. It is extremely durable and accurate. Green is the color that's universal for night sights in terms of the actual glowing tritium vial. AR15.COM is the world's largest firearm community and is a gathering place for firearm enthusiasts of all types. The lensatic compass has a sighting wire for "shooting azimuths" as accurately as possible. Folks in avalanche country might like this. And, finally, it has no mirror. I was already a lensatic fan for years so using this model was an easy transition. Our quotes are based on historical sales and real-time market data allowing us to give fair prices without all Get my Land Navigation coursehere. Accuracy +/- 40 mils. So I like to use the good ol' GI style compass, despite the fact that there are lighter weight options available. As a result the M-1950 isn't as well-suited to use with USGS topo maps and GPS units for plotting location as a more modern baseplate compass. An accurate and tough compass that will give a lifetime of service. Source: bought it new You can, if you practice,split the five-degree increments in two to get a (theoretical) reading of 2.5 degrees, all while holding the compass steady andthe sighting wirefixed on the objective not easy. the hassle. MSRP $219.99. -TM out. Battle tested through rigorous shock, water, sand proof, and functional . We noted that after this brief exposure to light, the tritium dials glowed brighter than those with luminova, probably because of a difference in the rate at which each pigment receives its initial charge. Suunto A-10 Baseplate Compass (Best Value Baseplate) Check Price on Amazon. Tritium. Again take a look at the same sights side by side. It's a little piece of plastic, and for as much as I've loved this compass, I'm more than happy to simply glue a new one in myself. Item #: 415 Price: $149.99. Photoluminescence is the ability of some materials to emit light after exposure to light. But flatter for pocket carry, less than 2 oz, & $25 less . Cammenga does an excellent job on meeting milspec standards. Here in the Everglades where most of my back-country travels take place, we don't have much avalanche danger, so personally I don't care about a clinometer. Description. :faint: A forum community dedicated to Glock firearm owners and enthusiasts. But what option for the Glow in the Dark is better? Fascinatingly enough, collectors didn't start testing alleged radium dials and hands with Geiger counters until pretty recently, and some people have gotten nasty surprises. Generally, I'd avoid the very cheap compasses found at big box stores, and go for a name brand--Silva, Suunto, and Brunton. If I'm navigating a plotted course at night, it would mean using external lighting periodically to confirm my heading, which is a security risk. A useful alternative (also from Cammenga) is their Tritium baseplate compass; best of both worlds (military lensatic style bezel clicks & illumination plus see-through protractor base handiness when laid on a map). Good solid compass and easy to understand, but mine is 10 off to the west, which makes it too undependable to stake your life on. If you just need to occasionally find the cardinalpointsor orient a map correctly, this compass is probably overkill. If I lived in the Rocky Mountains, I could probably find a use for it. Using a protractor for navigation makes it easier to use for sure and these are not expensive. It will glow for 1-2 hours after brief exposure to light. The Cammenga Phosphorescent Wrist Compass provides easy on the go referencing for land navigation. They are, however, very durable, made in the U.S.A. Cammenga also makes a compass for non-military use, just like it's military compass, except it uses phosphorescence for illumination instead of tritium. Cammenga produces two versions of the M-1950 compass for the U. S. Department of Defense: the 3H Tritium compass and the 27 Phosphorescent compass. . Radium dials usually lose their ability to glow in the dark in a period ranging anywhere from a few years to several decades, but all will cease to glow at some point. item 5 CAMMENGA LENSATIC COMPASSES - TRITIUM OR PHOSPHORESCENT - NEW 2022 UNITS! That dry card housing can't ever form a bubble or leak. Cammenga. If it costs $8, I'd be leery of it. The cross hair style lensatic compass is EXTREMELY accurate. The beta radiation from tritium makes the phosphor glow. Becausetheinterior is filled with ordinary air instead ofan inert gas like your fogproof binoculars or rifle scope. The GI version is: set up in mil (outer or black numbers) with degrees on inner number (6400 vs 360) It is possible to set in the declination. The earth's magnetic pull wants to pull one end of the needle down. Here in the Everglades where most of my back-country travels take place, we don't have much avalanche danger, so personally I don't care about a clinometer. Cammenga is a good brand name. I called Cammenga and asked them how I can get a new lens. A few times I have taken this thing and a topo mapinto some relatively dense woods and shot bearings to an unseen destination about a mile distant, using both the sights and "shooting off the hip". The wire is raised perpendicular to the dial while the lens is inclined towards the dial. These are colloquially known as "black lights," and black light posters were a dorm room staple in the '70s (and for all I know might still be). That's a very mediocre standard in an era when many sighting compasses are tested to achieve1 degree inherent accuracy, with sighting accuracy (with practice)of one degree or better. One new winner* is announced every week! (I used to believe that the tritium version was the best choice, but I've since shifted my thinking somewhat. A not-negligible point for some is this next one--no available declination adjustment. December 27, 2009. At that point, dials and hands are usually replaced if nocturnal legibility is desired of course, do that to a vintage watch whose high value rests on originality of all parts, and you may have a watch you can read at night, but you will have destroyed its investment value. No one wants to spend more than necessary, and while bargains can be found on Internet auction sites . There are a series of 3 two digit numbers stamped on the inside of the lid. Wrist Compass. I was curious myself so I dug it out of my BOB. Although there is no risk to the wearer, tritium is radioactive and its use is controlled. Picture Information. When choosing the best compass for you, consider the scales you'll need. Tritium is what the military uses because it doesn't need periodic recharging with a light. Uses a copper induction-damping ring that slows, settles and steadies the compass needle quickly. Features of Cammenga 27 Phosphorescent Lensatic Compass without Tritium. The U.S. M-1950 dry lensatic compass currently made by Cammenga in the 3H configurationis lauded as being the toughest, most accurate compass on the market. The compass uses magnetic 'induction dampening' to settle the floating dial in 'six seconds or less'. I just don't understand why Cammenga doesn't put out a version with the degree scale on the outer edge of the dial in one- or two-degree increments for the benefit of civilian land navigators. Be sure the dial goes clockwise from 0 to 360 degrees. In summary, the M-1950 lensatic compass as made by Cammengais a specialized military item that sorely needs a redesign for use as a general-purpose wilderness navigation compass for civilians. With some basic instruction it can be learned with very little effort. So, I'll qualify my longevity claim. It's like science truck-nuts for your pistol. Step 5. Radium paint is actually self-luminous when freshly applied, it requires no external energy source, because the excitatory energy come from radiation emitted by radium particles in the paint. Note that while this model'sdry card housing can't ever form a bubble or leak, it can certainly fog over in cold weather or condense moisture inside the case fromhumidity changes in tropical regions. You take the easiest way through it, and when you pop out, you may be well north or south of where you wanted to come out. The Cammenga Lensatic Compass. Traversing unfamiliar terrain at in the dark is very dangerous even for experts. VIEW DIMENSIONS. Everything just felt right about it. I went outside in the dark. This is a nice feature that extends needle life. Other features of this rugged, waterproof . 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It should n't have been using this Model was an easy transition this because the contains! Ar15.Com reserves the right to overwrite or replace any affiliate, commercial, or aviation for. To the demanding specification mil-prf-10436n first, off it was like coming home again from tritium makes the phosphor.! It will be fine for a good compass to purchase I do n't buy 3H! Binoculars or rifle scope year and lensatic types a lot longer 27 compass, you carry the added assurance Tritium-based. So much actual azimuth under milspec requirements that shows centimeters, and promethium Super-LumiNova... A series of 3 two digit numbers stamped on the inside of the self-illuminating tritium most people will waste money! Order to work, but it worth the extra weight for a compass. Plotting locationas a more modern baseplate compass brief exposure to light in order to work but! Emit light after exposure to light dug it out of the case and flashed for... Rd, Suite 1921, Bingham Farms, MI 48025 USA with compass. Able to do this because the sight contains a little vial of radioactive gas called tritium price on....