apollosmith

Nope. NGS does not take user submissions for new benchmarks. There's not much you can do other than enjoy the fact that you found a new mark. If it's not in the NGS database, you can't record it at geocaching.com or make an NGS report. You can, however, add it to Waymarking.com.

GPS receiver elevation calibration is about worthless. While you can calibrate them to increase accuracy quite significantly, the calibration is only good for a very short period of time and only within close proximity of the calibration point. If you turn the receiver off, move it more than a short distance, or wait more than a couple hours, it will be no more accurate than without calibration. The only time I calibrate is while benchmark hunting. I calibrate to an adjusted elevation point and then measure accuracy of the unit between benchmarks. It's quite good, but only under the parameters listed above.

If it doesn't have a PID (or at least didn't when they pulled their version of the database), it won't appear on geocaching.com, so it can't be logged there. And you can't submit a recovery log to NGS for a mark that's not in the database. You can, however, log it at Waymarking.com. The issue is that folks are logging the disk that is at the visitors center as the mark, when in fact Devil's Tower itself (or more accurately, something roughly close to the middle of the tower when viewed from a distance) is the mark.

Do you mean that they incorrectly logged the R 4 benchmark? Or that R 4 is a bogus benchmark (perhaps implemented entirely to sell paperweights)? What I don't understand is how the location for the actual mark can be ADJUSTED? "THE APPROXIMATE CENTER OF THE TOP" sounds anything other than an accurate location.

They are semi-active. The trains run very infrequently and only on set days and times... like clockwork. And not on the day we went. Even then, we were very attentive and stayed off the tracks except to cross. We were very clear in explaining this to the kids, who had a very fun time. All they ask about is when we're going benchmark hunting again.

Yep, $242 at Amazon. There's a video of it in action at that demonstrates very well how the true horizontal distance works. Unfortunately, it does not have a tripod mount. There's also the Nikon Forestry 550 which has a lot more functionality for angular and distance measurements. But, also (inexplicably) no tripod mount. A search for Hypsometer Rangefinder shows several other similar products. I had also purchased the Bushnell Scout 1000 Arc. It has a 1000 yard range, 1 yard accuracy, and a tripod mount. But it only shows true horizontal distance below 100 yards. As a rifle hunter in the Rockies, knowing the true horizontal distance at long distances was critical functionality, so I returned it for the Nikon RifleHunter 550.

I just purchased a range finder for deer hunting and realized that it would be perfect for rough measuring described distances from datasheets. Anybody else use a rangefinder for this? I purchased a Nikon RifeHunter 550. It's accurate to 18" at <100 yards and to 1 yard at >100 yards and has a range of 550 yards. This is MUCH more accurate and easier than GPS measurements, but less accurate though infinitely easier than pulling tape or running a wheel. It also has an inclinometer and can also tell you true horizontal distance. For example, you can point at the top of a visible object or building and it will tell you the horizontal distance to the base of that object (assuming a 90 degree angle). Seeing as all surveying measurements are true horizontal distance, this could come in handy. Additionally, you could also record the true distances for both the top and bottom (or top and calculated horizontal distance) of an object (e.g., a smoke stack) and with some basic Pythagorean Mathematics you can get a good estimate of the height of the object. Anyway, it's going in my benchmark hunting toolbox if for nothing other than the geek factor.

Thank you for your recommendations. I just made my first batch of 12 recovery submissions! A few questions: - Is there a way to search for GEOCAC recoveries for my area? I've looked through records for many hundreds of nearby benchmarks and have yet to find a GEOCAC observation. Any other way to find others doing this in my area? - The submission form asks for initials, which I entered ("JWS"). I noticed the Holoscenes Statistics page lists observations by initials, but my initials are already taken by an inactive member with 3 old recoveries. Will my observations show up? Under "JWS" or something else? - Is all this effort really worth it? I mean, it's fun to find these and log on GC.com, but are the NGS recovery submissions really useful to anyone? There are so few recent observations (like maybe a couple in my county), I wonder about their utility.

Here are a few draft recovery reports. Please provide recommended modifications. MS0001 - Not Recovered Union Pacific Railroad Station and elevated water tank are no longer extant. No indication of raised concrete foundation in vicinity of coordinates or the described location. MR0497 - Good HH2 coordinates N41 49 58.0, W111 59 31.9 (I assume that because it was found as described, the above is adequate. Correct?) MS0003 - Good Small telephone company building is no longer extant. HH2 coordinates N41 51 57.1, W112 00 53.2 MS0004 - Not Recovered Semaphore NO. 47.7 not present, though concrete base possibly buried. The nearby MS0005 (K 331 RESET - monumented 1950) appears to use this mark's original 1937 disk with "RESET 1950" stamped on it. MR0484 - Poor, disturbed, mutilated, requires maintenance Disk is present, but mutilated and unreadable. Along Union Pacific Railroad, .75 miles south of Trenton and .25 miles north of 9400 North. Cottle siding no longer extant. HH2 coordinates N41 54 24.5, W111 56 44.7 (Is this additional, updated detail necessary for a mutilated disk?) Other questions: - Should I comment on status of witness posts? - Should I indicate overgrowth or other things that may make the mark difficult to use or find? - Anything else I'm missing?

No, but these look like a lot of fun! This photo is all I have - http://img.geocaching.com/benchmark/lg/106...1af07650d16.jpg I rough measured the calls for MS0004 and the arrow points to the approximate location (within a few feet). You can see the switchstand in the background. Photo facing ENE. I dug about a foot and couldn't find a concrete base. As southpawaz noted, K 331 Reset appears to have used the original disk. I'll provide this documentation in my recovery log - though will, of course, log it as "Not Found" rather than "Destroyed". MS0001 is much more difficult because the Union Pacific station was torn down over 20 years ago. Taking my best guess at the original location and measurements from the rail puts it in somebody's front yard. There were no raised piers in view, and the threatening dogs made asking the property owner quite unappealing.

There's something special about finding benchmarks that haven't been logged or recovered in many years. It sure beats exchanging geoswag and looking under lamp post skirts. I took the kids today and we found 5 railroad benchmarks that had no recent geocaching.com logs or NGS observations in recent decades - MR0497, MS0793, MS0003, MS0005, and MS0006. We also made logs on two that are probably gone or unusable (MS0004 and MS0001). Do you think these are good candidates for making NGS logs? If the effort might provide useful information for someone in the future, I'd be happy to provide quality observation logs - I have updated coordinates (the posted ones are all of by more than 100 feet), photos, and descriptions on each mark.

I have the same set up. I have Topo USA and GSAK running in Windows XP on VMWare Fusion. It takes just a few seconds to boot into Windows and get things running. You have to disable 3D View in TopoUSA and VMWare has to be set with USB 2.0 disabled. Other than that, it works splendidly with my PN-40.

And I travel OUT of Salt Lake City a lot, so if you'd like a bug to head out from there, I could possibly pick it up at a cache north of SLC to Cache Valley (yeah, that's really what it's called - cool, huh?). I go to San Jose, Austin, and Pittsburg/West Virginia in the next month or so. Send me a PM if you're interested.

Agreed. But the PN-40 requires a very high battery draw. When your PN-40 says the batteries are dead, they are actually still 2/3 charged. Just take them out and put them into toys, remotes, or whatever and they'll run for a long time (probably for a couple years in a well-used remote control). I just cycle my AA batteries from my PN-40 to anything else that needs them. I also have it plugged into my computer via USB while at home and in a power port to USB adapter when in the car. It uses no (or at least very little) battery power when plugged in with USB.

A big +1 to Bosn Ski. I've tried all of them and found GSAK to be the easiest, most customizable, and most stable platform. I'm running it in Parallels on my Mac Book Pro. Here's my process: 1. Save the PQ .zip file and then open it in GSAK (or drag it onto GSAK). Filter how you want. 2. Open the relevant file on the PN-40 with Menu... Waypoints, then Menu... File... Open (or New, if you're creating a new file/batch of geocaches). 3. Upload the waypoints from GSAK with GPS... Send Waypoints (be sure to first select your GPS from GPS... Setup). 4. Save the newly uploaded waypoints on the unit with Menu... File... Save. I have many different files on my GPSr for different areas, categories, and types of geocaches. Each has its own database in GSAK. It's a bit confusing because although geocaches are uploaded from GSAK as Waypoints and they are saved as Waypoints on the unit, they do not appear under Waypoints on the unit. You have to go to Menu... Geocaches to view them despite the fact that the file functions all happen in the Waypoints menu.

All US and Canadian airports, air traffic control, and weather services.

I started compiling a response to another post and it turned into a full-fledged overview of GPSr barometric altimeters, so here it is. If there are inaccuracies or errors, please let me know. This was mostly an effort for me to learn what they heck these things are and how to properly calibrate them. Barometric Pressure and Altimeters Modern GPS receivers (GPSr) often include a barometric altimeter. Barometric pressure is essentially a measurement of the weight of the air above a given point. When a high pressure weather system is in the area, barometric goes up because the air is more dense or heavier - this is what pushes the rain clouds away. Low barometric pressure usually means more clouds. Barometric pressure is typically reported in inches of Mercury (e.g., 29.92 inHg) or in millibars (e.g., 1013.25 millibars). A barometric altimeter is tool that measures the amount of air pressure at that location. A GPSr with a barometric altimeter can provide more accurate elevation data (sometimes within 10 feet or so) than it can obtain from using the GPS satellites alone (sometimes within 100 feet or so - yes, elevation accuracy from satellites kinda sucks, and it gets worse as your elevation increases because you're closer to the satellites making it harder to determine your distance from them). A GPSr with a barometric altimeter knows that if the pressure decreases, that there is less air above it. Thus one of two things has occurred - either the GPSr has moved to a higher elevation OR the natural barometric pressure for that location has decreased due to weather changes. The problem is that the GPSr doesn't know which has occurred. Altimeter Calibration To get accurate elevation readings, the GPSr must be calibrated so it can equate a pressure reading to an elevation. There are four ways to calibrate the GPSr barometric altimeter: 1. Enter the KNOWN elevation when your barometric pressure is unknown. 2. Use the GPS-calculated elevation when your barometric pressure is unknown. 3. Enter the ADJUSTED barometric pressure when your elevation is unknown. 4. Let the GPS-calculated elevation help auto-calibrate the barometric altimeter over time. Method #1 tells the GPSr that the currently measured barometric pressure in the GPSr is what should be expected for that exact elevation. Method #2 does the same thing, except that it uses the rather inaccurate (+/- a couple hundred feet) GPS-calculated elevation. Method #3 allows the GPSr to determine the current, accurate elevation by determining the difference between the measured pressure in the unit and the sea-level adjusted pressure you provide. Once the GPSr has a good idea of what the accurate elevation is for the internally measured pressure, changes in pressure can more accurately be represented as increases or decreases in elevation. For example, a pressure change of .01 inch of mercury as measured by the internal barometer equates to ~10 feet of elevation change. But, your GPSr assumes that the the only thing that changes pressure is it moving higher or lower - it ignores the fact that weather also affects pressure. Thus, if the atmospheric pressure around you changes, your elevation accuracy will suddenly be out of whack. This means you should only calibrate your altimeter using pressure or elevation if you want increased accuracy over short periods of time (shorter if the weather/pressure changes) and if you'll remain within a small geographic area (because changing locations is more likely to result in an atmospheric pressure change). So which calibration method is best? Methods #1 (known elevation) or #3 (known pressure) arguably provide the same level of accuracy, though using a known elevation is typically better because it is a finer value than the measures used for barometric pressure. Either way, the calibration values should only be entered outdoors, out of the wind (which can arguably affect barometer readings), and once your GPSr has been on, immobile, and well established for some time. All GPS altimeters require good GPS reception AND accurate pressure readings. Using the GPS altimeter in your car or indoors will not result in high accuracy - and could result in VERY poor accuracy (e.g., 1000's of feet off). Letting the GPS auto-calibrate the altimeter is BY FAR the easiest - and by far the most accurate over long periods of time or distance or weather. This method uses the GPS-computed elevation to hone in on a 'best-guess' elevation and then uses the altimeter to help maintain accuracy and consistency of the displayed elevation over time. Most units recalibrate every 15 minutes using this method. Once your GPS location is well established, the accuracy of auto-calibrated altimeter readings are only slightly less accurate than manually calibrated readings. The advantage of auto-calibration is that you can be assured that natural pressure changes are not distorting elevation readings over time. In short, there really are very few advantages to manual calibration over auto calibration. Perhaps the only notable advantages are increased accuracy within a short period of time after proper calibration and that most manually calibrated GPSr units can provide high accuracy almost immediately after turning them on - you don't have to wait for the unit to establish your position before getting a highly accurate elevation reading (e.g., the unit can read the barometric pressure much faster than it can triangulate your position). If you calibrate your GPS altimeter with known pressure or known elevation, you must turn off "Auto-calibrate" function in your GPS otherwise it will ditch your entered value and go back to the best-guess GPS elevation in a matter of minutes. Most units prompt you to turn this off after manual calibration. But be sure to turn this function back on later otherwise the reported elevations will likely be WAY off because the pressure will likely have changed. Some tips on using pressure calibration If you choose to calibrate using a known pressure value, be sure to use sea-level adjusted pressure readings (sometimes referred to as ASL, MSL, or elevation adjusted). You can get these from local weather reports and from airport METAR reports. METAR reports for your local airport are available here - just find the numbers after the A and put a decimal point in the middle. For example, my local airport METAR contains A3035, so my current sea-level adjusted pressure is 30.35 - or 30.35 inches of mercury. METAR and weather station pressure values are typically accurate for perhaps 100 miles from the reporting station/airport (naturally less if the weather is changing). Your GPSr expects an elevation adjusted pressure. The pressure can typically be entered in inches of Mercury (inHg) or in millibars. If you're using a home weather kit, barometer, or get the pressure from another GPS system or weather station data feed, these will typically NOT report elevation or sea-level adjusted pressures. Using these values will cause great inaccuracies - higher inaccuracies the higher your elevation. Because one inch of change in mercury represents ~1000 feet of elevation, if you live at 5000 feet elevation, your elevation adjusted pressure might be 30.10 inches, but a barometer would probably show a local (unadjusted) pressure of 25.10 inches. If you enter 25.10 inches into your GPS, elevations shown on your GPS will be off by 5000 feet!!! Some tips on using elevation calibration The optimal method for calibrating using a known elevation is to use an elevation benchmark. Go to http://www.geocaching.com/mark/ and enter your zip code and try to find a benchmark you could use (U.S. only). Be sure to look for one that has recently been found in good shape (has a smiley face icon) and that has an adjusted (e.g., very accurate) elevation (check the description for "Altitude is ADJUSTED"). Benchmark elevations are VERY accurate - usually within a few 1/10s of an inch - pretty remarkable considering most were placed in the 20's and 30's. Because the GPS unit itself is only accurate to within 10 or so feet of elevation at very best, you may be just as well off using a good topographic map or even Google Earth to determine your location's elevation for calibration. One good method is to use a benchmark initially then use that to determine your home's elevation - then use this elevation to calibrate your unit each time you leave home. Be sure to measure an elevation outdoors - taking it inside or calibrating inside will ruin your accuracy. GPS altimeters and aircraft altimeters It is important to note that airplane altimeters and GPS altimeters may vary a lot except when on the ground. One reason is that the airplane altimeter uses the pressure at some nearby airport to provide a basis by which the elevation is determined. This is why pilots are constantly updating the pressure setting on their altimeter - not only to ensure accuracy for when they land or fly over local terrain, but also so that their pressure setting is the same as every other plane's in the immediate vicinity. When you're flying at 15,000 feet, the pressure will be significantly lower than at the airport below because there is less air above you than the airport (just like the local, unadjusted pressure at Denver is much lower - ~5 inches of mercury lower - than at sea level). But you want all airplanes in the immediate area to have one uniform pressure setting in their altimeters - otherwise you could risk collisions. One plane flying at an indicated altitude of 15,000 feet with a pressure setting of 29.75 and another plane with an indicated altitude of 14,000 feet but a pressure setting of 30.52 will be MUCH closer in ACTUAL altitude than 1000 feet. Planes flying above 18,000 feet tend to fly faster and thus use a standard pressure setting of 29.92 so that all planes up there are reporting the same indicated altitude and don't have to update their pressure settings every few minutes as the pressure at the ground changes below them. Because of this standard setting, a plane flying at 35,000 feet with a standard pressure setting of 29.92 might actually be flying much higher or much lower than 35,000 feet above sea level. All that pilots care about is that what they think is a certain altitude is the same as what everyone around them thinks. They only care about really accurate altitude when landing. If you take a GPS on your flight (make sure it's OK with your airline before using it in-flight!), you'll notice that the GPS elevation and the reported airplane altitude may vary a lot. Also note that GPS elevation accuracies decrease slightly as you gain elevation. Oh, and be sure to disable your GPSr barometric altimeter on a pressurized plane or the results will be, well, WAY off.

I'm curious as to why you feel the need to calibrate - it will do little good unless you need/want accurate elevation recordings while in the immediate vicinity and time of the calibration. Calibrating in Buffalo and then flying a pressurized plane to Toronto will not do you any good - you'd be better off just using the GPS-reported elevation. One option is to go to http://www.geocaching.com/mark/ and enter the zip code and try to find a benchmark you could use (U.S. only). Be sure to look for one that has recently been found in good shape (has a smiley face icon) and that has an adjusted (e.g., very accurate) elevation (check the description for "Altitude is ADJUSTED"). You can also view them on a Google Map at http://benchmarks.scaredycatfilms.com/ I highly doubt you'll be able to find one INSIDE an airport, however. The only benchmarks I've seen at airports are in places that will get you a cavity search and probably a few days of interrogation (at least) if you try to get to them. You wouldn't want to calibrate it inside anyway because the barometric pressure will be off. And even if you do use a benchmark, the accuracy of the elevation reported by the GPSr is not terribly precise even after calibration (+/- 10 feet at very best). (Benchmark elevations, however, are VERY accurate - usually within an inch.) The GPS-derived elevation is fairly accurate (+/- 100 feet at best). You'd probably be just as well off using a good topographic map or even Google Earth to enter the elevation for calibration - you'll probably be well within the error of the GPSr. Another option is to ask the pilot when you get on or off the plane for the current pressure reading (make sure to ask if it is current) and then enter it in the GPSr while still in the jetway. You can also get the current pressure readings for airports or weather reporting stations online. If you're at about the same elevation and within 25 miles or so, use this. Again, this will put you well within the accuracy of the GPSr.

I recently did A LOT of research and playing around with these two units before deciding on my first GPSr. For me, it came down to the following: - Screen - PN-40 has a smaller screen, but it is easier to see and seems more detailed with better contrast and brightness. - Mapping - PN-40 is the best, hands-down. The built-in maps are MUCH better than the Garmin and for $30/year you can get all the satellite, USGS, waterway, etc. maps (and even layer and customize them in your GPS) you want through Delorme. It costs 10X this much to just buy the Garmin maps that make it even equal to the Delorme out of the box. If you want high quality maps and want to add to your map collection, Delorme is the answer. - Road routing - 60CSX. The road routing on the Delorme is very weak, inaccurate, and slow. If you are using this for your car GPS, the Delorme is probably not the best pick. - Battery - slight edge to the 60CSX. However, I found myself wading through the menus and looking at the 60CSX a lot more, possibly negating any battery advantage. - Usability - Definitely the PN-40. Garmin users complain about how difficult the Delormes are, but it's really just that it is very different, not bad. I sat them side-by-side and tried to figure out basic functions without the manuals and with very little prior experience with either and the Delorme was MUCH easier and quicker. - Accuracy - I could tell no difference at all. Both are very accurate. I experienced the same levels of drop-outs with both units. The Delorme picked up twice as many satellites in my house as the Garmin - though I don't do much GPSing indoors. - Software - I'm not sure here. TopoUSA would take the vote here, but I'm a Mac user and it is not Mac native. I have TopoUSA running in VMWare on my Mac with good success, though the 3D view causes the program to crash (still working on a solution to this). Because of the Delorme map subscription service, I have to go with Delorme here - though their software is MUCH more difficult to use and learn. As you might have guessed, I went with the PN-40 and have been very happy. I'd probably also be happy with the Garmin, but it was ultimately the better mapping functionality (especially the high resolution satellite imagery) of the PN-40 that tipped the scales. I feel like I can go hunting with the PN-40 and could leave the USGS maps at home - I'd definitely need them in conjunction with the Garmin in order to go into the back country and be very comfortable with where I'm at and going.

FOUND IT!!! Well, at least MR0489. I have several questions below about MR0488 and a few other things. First of all, thank you all for the insight and ideas. Your recommendations were spot on and it was an easy find. We also nabbed MR0483, MR0485, and MR0484 - three very interesting and distinctly different marks on this, our very first benchmark hunting trip. None had previous logs. Pics posted of all three. Any thoughts as to why MR0484 has been defaced? It does not look like vandalism, but instead like it was defaced intentionally so as to be rendered unusable. There was a relatively fresh 'X' painted on the bridge it was located in and the bridge was in poor repair, so perhaps it was defaced in preparation for a future bridge replacement? MR0489 was found as described, even though many of the items described in the datasheet are gone. As you can see here, the old motor car set-off is gone, but it's bed is still in place. This picture was taken from South of the marker and is facing North. Note the 5547 post at a culvert - supposedly at mile 55.47. Also the 1/2 "milepole" - 55.5. The blue thing just right of the semaphore(?) is my daughter at the benchmark. I didn't really look much for MR0488 because I didn't see what I considered a semaphore, but then when I got back and checked the pictures, I started wondering if the "X" marker noted in the photo is perhaps the semaphore or likely the location of the original semaphore. The datasheet for MR0488 sure seems to match this location. Perhaps I'll go back in the spring and see if maybe the marker is in the base of this pole or nearby. And finally, another photo of a railroad milepole or milepost - note the 4 bands indicating the full mile mark and the mile designator. This was very near MR0484 Thanks again for all of your help with this find! We got 4 marks all within a mile or so of each other. I'm sure it's the first of many trips as you can see by the look on my daughter's, er, I mean "Chief Locator's" face:

Yep, the search results time out after a few minutes, so you have to move quickly or just open each page in a separate browser window. You should also check out - http://benchmarks.scaredycatfilms.com/ This uses a more updated database and provides links to both the NGS and the Geocaching.com database.

Doh! I meant telephone pole SHADOWS. They are clearly visible in Google Earth when fully zoomed in. Assuming these are original (not likely) or perhaps spaced the same, then yes, they could be very helpful. At a minimum, they give me some measure of distance - I hope they follow the entire line, though I don't recall seeing them before. There are 50 or so markers along this line within 15 miles of my home - most of which have not been verified since the 60's. It will give me lots to do. And some very cool sounding ones on dams and bridges. I know that quarter and other inter-mile markers are much more common out here in Utah and Idaho than in other places - particularly on parallel telegraph poles. So I might be in luck. If only spring would hurry along. I'll try to sneak out to this particular site and dig around a bit over the Christmas break. I'll certainly report back on what, if anything, I find.

Thank you all for taking the time. You've given me much to think about. mloser - I fully agree with your assessment. In looking closer at Google Earth, I can see reflections from telephone poles, so the pole references may be more helpful than I thought. Now I just need to get out there and look. The problem is that there's 8" of snow on the ground, so it will probably be spring before I get to some of these more difficult marks. I'm starting with some easier ones along the same line - ones set in bridges, switches, and culverts, then when the weather turns nice, I'll work up to some of these more questionable ones. Thanks again! One last question (I think) on something I couldn't find in the available resources - in checking the newest NGS database, I see that there are updates by 'geocachers' verifying status and condition of some benchmarks. How does one go about submitting updates to the NGS? Or do they simply pull them from geocaching.com?

The Salt Lake Olympics one, appropriately designated "OLYMPIC", is in the database, including photos - http://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=DF4639

Ah. I see. Thanks for the clarification. So for the two benchmarks in question (http://www.geocaching.com/mark/details.aspx?PID=MR0489 and http://www.geocaching.com/mark/details.aspx?PID=MR0488), it's very likely that MR0488 (the non-RESET one) is probably not there any more. With the only description being in 1937 (vs. 1967 for the RESET), this all makes a lot more sense.