tritium vs phosphorescent compass
View All Outerwear, Clothing, and Accessories , Top 25 Now in defense of the Silvas - if you're a part time land navigator and do not have a need to cross really tough areas the Silva is more the good. Note the official military'shock' test an easy 'drop' test of 90 cm (3 feet) onto a plywood table covered with a 10 cm (4-inch) layer of plastic-covered sand. Not a beginners compass, but not hard to master either. Many were unpleasant where accuracy was/is critical. 1960s era black light poster. Strontium aluminate seems to be a highly stable phosphor, and Super-LumiNova dials, at least thus far, appear to not suffer from the gradual phosphor degradation characteristic of radioluminescent materials. Strahwk One new winner* is announced every week! On the other hand we would also like our dials to age well, and inherent in the nature of many luminous materials, is that they will sooner or later dim to the point of uselessness. . Secondly, the ability to easily navigate in really difficult terrain is far better and more accurate. Overview. Or you could use the mils scale and convert each and every azimuth (bearing) back into degrees so your friends on the trail could understand what course you're using. It also has no adjustable declination feature for relating all compass headings to true north. Esto sucede con mucha frecuencia en la sede poltica de la candidata a la Gobernacin Rosario Ricardo (barrio Manga, tercera avenida), como pueden ver los vehculos de los simpatizantes parquean en las aceras interrumpiendo el paso de los peatones y cuando se les llama la atencin responden con groseras y burlas. Wrist Compass. When perpendicular (fig. The compass also comes with a nylon carry case, a lanyard, and belt clip for the case, as well as a brief instruction manual written in very direct military style. I called Cammenga and asked them how I can get a new lens. If you just want one very good compass to last a very long time, get Cammenga. Looking for specific info? Wherever you are on planet Earth, your watches are protected. While the exact quantum mechanical description of photoluminescence is complicated, the basic idea is simple: if an electron orbiting an atom in a certain material absorbs a photon, it will be excited to a higher energy state, and when the electron "relaxes" to its ground state, it emits a photon which we see as visible light. +1, it will be fine for a long time. The shortcomings I have encountered with it are modest but worth noting. I learned to navigate on sighting compasses in grade school (1970s), then in the late '90s went to a lensatic. Exactly how long Super-LumiNova will retain its ability to glow is unclear it seems safe to assume that sunlight can cause the material to break down eventually and if the vintage watch craze has taught us anything, it's that nothing lasts forever; but it seems, in general, a very durable material. Cammenga 27CS Lensatic Compass. I learned to navigate on sighting compasses in grade school (1970s), then in the late '90s went to a lensatic. Uses a copper induction-damping ring that slows, settles and steadies the compass needle quickly. You could easily do that with a glow-indicator compass. Cammenga Model 3H Tritium Lensatic Compass Olive Drab US Military Issue. When buying a Cammenga, they offer you the option of Northern Hemisphere or Southern Hemisphere. Folks in avalanche country might like this. It is water and sand proof, and is functional from -50 F to . It is adversely affected by moisture, so a high humidity climate might cause issues, but in general, Super-LumiNova and other strontium aluminate-based pigments seem likely to be with us for a long time. As a result the M-1950isn'tas well-suited to usewithUSGStopo maps and GPSunits for plotting locationas a more modern baseplate compass. Subscribe to our monthly Newsletter to receive firearm news, product discounts from your favorite Industry Partners, and more. However, if the bezel is original it's basically just as radioactive as the day the watch was made an important caution for any collector who owns one. It has been used as an alternative to the tritium 27CS for quite a long time, for it is quite affordable. As a result, the degree scale is only marked in large five-degree increments a dial you'd expect on a $10 compass, not one costing$50 or more. I like the compass, but I'm extremely dissatisfied with the Cammenga. This compass features both a 0-6400 mils scale (20 mil resolution) and a 0-360 degree scale (5 degree resolution), with an accuracy of +/- 40 mils. Some people say use a dot of phosphorescent paint instead. Two of the best known users of tritium gas tubes for watch dials are Ball and Luminox. In order for phosphorescence to take place you need an energy source, and a so-called "phosphor" a material that will absorb and re-emit light. Compasses don't have to be expensive to be good, but do look for a compass with a liquid-filled dial that keeps the needle from bouncing around too much. Luminova was invented in 1993 in Japan, by Nemoto & Co. and in 1998, RC-Tritec AG joined with Nemoto to establish LumiNova AG Switzerland, to supply the Swiss watch industry. Silva Polaris Compass; 2.5 6. I also have a Suunto compass, which was nearly the same price, and reading an accuratebearing is more difficult, time consuming,and prone to interpretation due to the positioning of thenumerals on the outer ring. Sale price: $37.50. Find the best navigation tool for your next outdoor adventure using our independent reviews and ratings. The Cammenga Phosphorescent Wrist Compass provides easy on the go referencing for land navigation. Lasts about 10-12 years, then donated to scouts. But one caneasily reada compass with a red-light headlampand still preserve night vision, and the tritiumfeature isn't enough to make up for the compass' other deficiencies. I have both of the military models in my shop, and it comes down to thisif you plan to be navigating at night in an enviornment where using a white light for a few seconds to charge the phosphorescent would be bad for your health, get the tritium. Some are offered in contrasting colors. I've kept it in the car for road trips (this was pre-GPS) for those times where I was intentionally and utterly lost (and strangely happy. Low areas where you must constantly shoot accurate azimuths, etc. With the compass held to your eye you align a notch on the lens holder, wire, and target much like iron sights on a rifle. Besides that, there is the issue of inherent accuracy. How does radium paint behave under a black light/UV flashlight? If a lot, the get the tritium. That means some of the liquid has leaked out. Bottom Line. The Cammenga G.I. Ever. Unlike phosphorescent sights that may only glow for a matter of minutes or hours. | updated August 14, 2012. When choosing the best compass for you, consider the scales you'll need. Very well built, impressive compass, at least until the lens fell out. $109.99 I would never willingly own one without Tritium. Posted: 1/16/2012 1:33:21 PM EDT. Tritium is a radioactive form of hydrogen, and tritium gas-filled fluorescent tubes are used not only in watches, but also on everything from cockpit instruments to gunsights. A lensatic compass has a lens and wire which can be unfolded. jett Because the latter is a gimbaled design, I can even take accurate compass readings while walking or riding in a small boat or canoe. mike068 In the northern hemisphere, it pulls the needle's north end down. 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. The military lensatic compass comes with either tritium or phosphorescent illumination for night navigation. 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. . You can, if you practice, split the five-degree increment spacing in half to get a (theoretical) reading of 2.5 degrees between increments, while simultaneously holding the compass steady and the sighting wire fixed on the objective, then checking for parallax error not easy. Come join the discussion about optics, gunsmithing, styles, reviews, troubleshooting, accessories, classifieds, and more! This is because in phosphorescent materials, the excited electron is in a special energy state, in which the re-emission of a photon would require a "forbidden" energy transition. Then by looking through the lens you can read the bearing off the dial. 3. I lent it to my son and he returned it missing the lens. My 159-page, fully illustrated book is yours for the asking. Emission of an alpha particle. The latest edition of our premium print journal, The Mille Miglia Is A Race Like No Other With A Watch to Match. For those who need night illumination, the tritium has an effective life of about 12 years, after which the compass is difficult to read in the dark. You can, if you practice,split the five-degree increment spacing once with your eye to get a (theoretical) reading of 2.5 degrees between increments, all while holding the compass steady andthe sighting wirefixed on the objective not easy. Some are day / night, some not so much. Oh shit I didn't know the phosphorus wore out too and faster. It's the standard issue military compass. $27.76. Tritium GI compass cause it is what I know nd am comfy with. Price Paid: $90, Reviewed by My preference for Tritium is front and rear for quicker acquisition and alignment. This is NOT a replica. The second quibble is that the scale markings along the straight edge available when the compass is completely open are suitable for 1:50,000 scale markings, but some of the markings (specifically, those for 2000 and 4000 m) aren't marked so as to quickly distinguish them from neighboring marks. Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. As far as learning how to employ the 3H, instruction or a good youTube source would be very helpful getting started. In summary, the M1950 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. For a better experience, please enable JavaScript in your browser before proceeding. . One other thing I like about the Suunto M-3G is that it has a "global" needle. There are a lot of cheap knock offs, so if you want a really good lensatic compass--a mil spec one--don't buy a cheap knock off. Source: bought it new $ 48.00 - $ 119.00. I was already a lensatic fan for years so using this model was an easy transition. Have Tritium on a couple of 1911s and have never had on a rifle. The compass dial should turn freely, but not too freely. Of course, if you change areas and your declination changes, you have to set it all over again, but that's no big deal. $24.81 + $5.65 shipping. Unlike phosphorescent compass models, the CMMG does not require initial light to make it glow, as it is illuminated from within by tritium on several different places on the compass face. Price Paid: $79.95, Reviewed by The decay chain finally ends in a stable isotope of lead, but you get things like polonium and thallium en route. The compass itself is built with attention to detail and all partson my example were well-fitted with no signs of manufacturing or assemblydefects. The Cammenga G.I. Bill I have been using this compass for about a year and lensatic types a lot longer. I bought one of these as a replacement for an old Silva compass. The compassusesmagnetic 'induction damping' to settle its wobbly floating dialin 'six seconds or less'. It worked well enough for that. 3. This compass is often praisedfor its superior accuracy over most baseplate style compass designs in shooting an azimuth (taking a bearing) to an objective or landmark. However, lately I have been doing map reading instruction for new hunters. Best overall: AOFAR AF-4074 Military Compass. Anyone have a link for a good compass to purchase? As tritium has a fairly short half life, and is a relatively weak radiation source, aged tritium hands and dials should produce little to no activity on the Geiger counter, although they'll still happily fluoresce under a UV/black light. They involve using some math and the clicks of the bezel as you rotate it. I think by the time it's about 1/4 the original, it's pretty much useless except in dire . You probable wouldn't even need a ponch. All rights reserved. Our patent-pending injection molded sleeve design not only holds our Tritium vials securely in place, it creates a brighter and more durable ring, we call The Perfect Dot, that provides maximum visibility both day and night. (Walking a straight line in any forest with no cleartarget in sightis always achallenge.). Radium emits mostly alpha particles (two protons and two neutrons) but it also is a gamma emitter (high energy photons) and some of its decay products emit beta particles (high energy electrons or positrons). I bought two of these compasses over the years. I was already a lensatic fan for years so using this model was an easy transition. Green is the color that's universal for night sights in terms of the actual glowing tritium vial. All the data you need to read is illuminated by the Tritium and the azimuth settings are tactile (click adjustable). So chances are, it might be fairly dim if its older than that. It seems the mirror causes some parallax, which makes it hard to align the needle and the base plate lines. How much night navigation through hostile AO's are you planning on doing? Brand-new, the G.I. I paid $70 for the bloody compass. Accuracy +/- 40 mils. The interior is white. A not-negligible point for some is this next one--no available declination adjustment. This is a nice feature that extends needle life. These are great,rugged,water and shock proof..top of the line ..shelf life of about 14 years at top of its illumination. Military Phosphorescent Lensatic Compass.
