Black Dog Trackers

2675

1. NGS measurements: Measured from nearest surface or center?

I had always assumed that reference mark distances to power poles was to the nearest edge of the pole and a distance to a tree was to the center of the tree. I assumed this because: it wasn't spelled out, and a tree will grow, whereas a power pole will not. With a distance to the center of a tree there's always going to be some uncertainty. We've all seen the rings on a cut tree and the center is not always in the center of the tree, especially in the case of hardwood trees. I have measured to trees and have assumed that measuring to the "the side of the tree at a perceived right angle to the line from the tree to the monument" as jwahl says would be sufficiently accurate to find the mark. I just did a calculation assuming a 30 foot distance to a reference tree that is 18" in diameter. Measuring to the side of the tree as described above gives a hypotenuse distance of just under 30.01 feet. The difference of 1/100 inch between that and 30 feet is 10x as precise as a feet-and-tenths measurement, and certainly precise enough for finding a disk mounted in a 10" or 12" diameter monumentation. It's probably precise enough for establishing the reference too. So, I'd say that mathematically, doing a measurement to the side of a tree at the tangent point is sufficiently accurate for either finding or establisihing a reference feet-and-tenths distance to or from a tree.
2. What is this

Hi 1mpinney1 - That is a U.S. Army Corps. of Engineers survey mark. It is one of thousands of benchmarks not included in the benchmarks database. You can read about that here in the benchmark hunting FAQ page.
3. Survey Mark Recovery Instructions

Excellent cookbook! I suggest that your cookbook address the various issues of units of distance measurement. Box score distances are in meters. To-reach and the rest of the verbal instructions are in feet-and-tenths. The person doing the recovery might have a tape in meters, feet-and-tenths, or feet-and-inches. So, in any case, some kind of distance conversions must be done, at least for triangulation stations. In my opinion, all datasheet distances, including box score distances if any, should be converted to whatever units the recovery person's tape has BEFORE going out into the field. That would put this in the area of your steps B and C. All computed positions and plots (sections D and E) should be made in the tape's units. Doing all these conversions at a desk and computer before setting out will greatly reduce error and frustration at the site. The same as above is true of all compass bearings. All datasheet and box score bearings should be converted to magnetic before going outside by using the proper declination, unless this can be done by some automated equipment means (my old Suunto won't do that). After returning from the recovery expedition, convert any new observed data to datasheet norms (feet-and-inches to feet-and-tenths (or meters), magnetic to true). That would be around step P. In the photos section, you might want to be more specific. One aspect to be specific about is the kind of photo from a short distance with the mark clearly in the view or at least with its position clearly indicated. A look in the benchmark gallery will often show some pictures "from the station", which are of no to-reach use. Looking at the benchmark gallery will also show a bunch of disk-plus-GPSr pictures. I don't know if you want to address that touchy subject. Certainly loads of "view from" and "with GPSr" pictures can be uploaded, but they shouldn't be at the expense of "pictures with" and getting a better closeup of just the mark. I realize that looking at the benchmark gallery is not exactly the same as looking at a group of photos submitted to the NGS but it does show some current practices. To convert from meters to feet, multiplying meters by 39.37 and then dividing by 12 is ultimately more accurate than 3.280833333 and is perhaps easier to do.
4. Problem Bridges

Well, the reset disk is not a find of LN0306. If a disk is stamped RESET, it is not the same station even if it is in the same place. If the RESET disk is to be part of the NGS database, then it will get a different PID. There's a similar situation here. After looking on the Google Images site for parapet, I believe that "parapet" is a synonym of "balustrade" in holograph's excellent bridge-parts drawing. Concerning JN0016, this is also not a find. The thing found just has to be the exact thing as stated in the datasheet. There's another similar case here at Mount Washington. All the found logs (over a hundred now, I think) are incorrect. Another disk was put in the same place. It is not a find.
5. I forgot..

I found a collection of posts on this subject. The last one has the thing I was remembering (vaguely).
6. I forgot..

foxtrot_xray - Good point. It is true that diskless stems and even stem-and-diskless holes are not as problematic if they are horizontal control. However, there was a case with several posts on it (pun not intended ) about a vertical control that was on a typical cement post mounting several inches high next to a railroad. The top half had been knocked off and was gone. Deb advised to log as found-poor anyway, even though it would be unknown how much height of the monumentation was gone. It was agreed that it was really really really Poor, but the conservative approach was what Deb advised. If somehow it was the wrong thing found, the finder's coordinates help lead a surveyor to the item to see and evaluate for himself. I can't find those posts on that one just now.
7. First time hunting... a bad sign?

ForlornWanderer - That's a good story about finding those marks! I enjoyed reading it. Finding the Azimuth mark too is definitely quite a coup!
8. I forgot..

That situation could be logged as: Poor, if you are REALLY confident that that is the correct location AND the liklihood that there was a replacement, which was also beheaded, is very low. Not Found, if you are NOT REALLY confident that it can be no other than evidence of the station you're looking for. Never log destroyed on a diskless stem or obvious disk's hole, at least don't claim destroyed to the NGS.

That looks like it could be honeysuckle. http://www.earlham.edu/~biol/brents/field_...oneysuckle1.jpg http://www.earlham.edu/~biol/brents/field_...oneysuckle2.jpg
10. Airway beacons

Hey, Rogbarn, good to see your smilin' face here again! I do recall the airway beacon searches. People had to use various spellings to catch them all. I will have to see what I can grep out. Is this for Washington State only?
11. Incorrect ID

That is somewhat like the benchmark waymark categories work. Instead of just deleting logs, they are sent back to the submitter for fixing with an explanation. This happens to only about 1 in 25 submissions. Then there are psychological issues of wanting to avoid being some picayune jerk and yet be useful in the position of basic quality control. There is a lot of programming behind that whole system as one might imagine and campaigning a lot for it might end up with benchmarking being stuffed into Waymarking and that would be painful to many, for whatever reasons. So, it might be best to think of the other, more passive solutions for benchmarking. How big a task would this be? In benchmarking: "In the last 7 days, 950 benchmarks have been logged by 347 users." Yeow!!! In u.s.benchmarks Waymarking in October so far (22 days) there have been 96 submissions, so that's about 30 per week; about 1/32 as much as in benchmarking. There are 6 of us doing the u.s.benchmarks reviews at the moment - whoever sees a stack waiting does them. So, for benchmarking review we might need 32*6=192 reviewers for the same (not too taxing, but always there) pace! We would never muster 192 reviewers, or anything close to that. There's another reason to not merge benchmarking and waymark benchmarks. The idea of more accuracy prompts in the logging software is a good approach for a couple of major things and shouldn't be terribly hard to do. Even that can become routine to get past when you have several logs to do and want to click away that the logging software at a fast pace. I don't agree with any idea of just laying down and doing nothing. Education is always useful. Surely those poor benchmarks close to geocaches get regularly logged incorrectly but those are only a tiny fraction of the 700,000. The forums are not the only place to learn benchmark hunting. The FAQ exists too, in an obvious place. I like the wiki idea MUCH better than a pinned topic but unfortunately none is hosted by Groundspeak at this time. With a wiki, everyone can participate in fixing up a nice educational system, and it can be brought up to date almost immediately if there are any required changes in procedure. As for the NGS, I continue to be amazed at the lack of any but the most meager instructions for logging (they do have good 'to-reach' instructions) on the NGS website. The idea of opening up the logging process to John Q. Public must've been a brave one, especially coupled with a lack of detailed instructions for reference.
12. Logging Intersection Stations to NGS?

LSUFan - Thanks for finding that! Now that I read it, it seems a bit less official than I remembered. So, it was a directive to the USPSQD that was noted here. So far, we at GEOCAC haven't been notified of this. Perhaps NGS Surveyor or DebBrown will go ahead and give us the official word here if that's what they want us to follow. PFF - I imagine it's a possiblity that the reason the NGS is not deleting all the intersection stations is because some of their 'data' is still part of some location adjustment universes.
13. What does this mean and should I go for it?

BlueMoth - Since GR1943 is an adjusted station (note the line on the datasheet: "Altitude is VERTCON and location is ADJUSTED"), its coordinates are extremely exact, much more so than your GPS receiver can measure. So, your GPS receiver should bring you within 10-15 feet of where the station mark is (or was). If you hang around with the GPS receiver for a while more as it jumps around, you will probably get an idea within 5-10 feet of where the disk should be. Generally when stuff is re-landscaped as much as you indicate may have happened there, the station mark and the 2 local reference marks are likely buried deep in a landfill somewhere by now; i.e. not saved. Benchmark hunting can be quite an interesting challenge sometimes!
14. Incorrect ID

NGS Surveyor - There are a couple of benchmark finding and logging 'cookbooks' that we currently use here (and a couple of sections following it), here, here (that one includes a link to the NGS guidelines), and here (a post specifically about NGS logging). Hopefully you can add more information about this important topic and give corrections for anything in those references that's not right. The present benchmark FAQ did seem to do a lot toward improving the quality of logs (and forum questions) after it went online, but as you can see, there are still problems that occur. One issue is the common lack of a 'distant' photo. A frustrating version is the lack of that kind of benchmark view, and instead a 'view from the benchmark' photo is in the log. Your interest of course is NGS logging, but accurate logging on this site can be thought of as part of the learning process for moving on to NGS logging.
15. What does this mean and should I go for it?

BlueMoth - There was no find of GR1943 in 2006. What's pictured in that log is Reference Mark number 4 for GR1943 and that does not count as a find. In the 2/1/2004 log, there is a picture that I assume is the actual mark GR1943, which is inside the electric company's easement fence. There are 3 reference marks listed in the description. They will all say "REFERENCE MARK" on their disks with an arrow pointing to the actual station GR1943. Finding any of them does not constitute a find. The actual station GR1943 will have a triangle in the center.
16. Logging Intersection Stations to NGS?

I have searched, and cannot find the post in which we were told about not submitting recoveries for intersection stations. If anyone can find it, please post the link to that post here.
17. Logging Intersection Stations to NGS?

We were indeed told that. Likely, many GEOCAC hunters don't read all the forum posts, if any. There's no official moratorium unless there's something in writing either in the geocaching site or the NGS site and I can't find any on either. I think the NGS has the right to ignore any such submissions if they want to, and to put them through if they want to do that instead. I have often heard of the guideline of 5 or 10 years, but the only actual NGS guideline I've seen is: "If the data sheet for this mark shows a recovery within the past 12 months and the status has not changed, please do not report it."
18. What is the difference in a BLM marker and Geodetic marker?

drgnflyz - If a marker is not in the benchmark database you can only log it in the U.S. Benchmarks Waymarking category. The vast majority of cadastral marks are not in the benchmark database, but a few are. I believe that most BLM markers are cadastral marks. Extremely basically, geodetic marks are for establishing positions on the planet, relative to either planetary coordinates or sea level, and cadastral marks are to establish property or administrative borders in relation to other borders. You can read about the benchmark database we use and why some marks are not included in it here.
19. The Mysterious State Park - Its on the Topo Map!

The USGS Geographic Names Information System can be searched with "Booker T. Washington" and Feature Class "Park". The results are 4 parks, National Monument and a playground. The last park is the one in WV. Clicking on it reveals this note: "Historical This feature has ceased to exist and/or no longer serves its original purpose."
20. Finding One By Accident

Yinnies - You don't need to inform anyone, especially since it's a new benchmark. There are many local databases that have thousands of benchmarks that are not in the database that we (or the NGS) use.

22. How to measure approximate elevation differences?

Transparent aquarium hose with water in it. A laser pointer and a long level.
23. Benchmarking/Caching

I started with geocaching. I did about 15 geocaches and that's it. Then I got interested in benchmark hunting and did a few hundred of those. Benchmark hunting offered the challenge of so much to learn about. It's technical and involves a bit of mathematics now and then. Learning about benchmarks and discussing their technical aspects was as interesting to me as hunting them. By comparison, geocaching seems (to me) contrived. People hide stuff from you and you must meet their challenge to find it. With benchmarks, they are supposed to be findable, but time tends to hide them and you must meet the challenge of time's effects to find them. Benchmarks are important to society whereas geocaches are not, so there is some difference in feeling about the hunt because of that. Both are hobbies, though, and they can be equally challenging, both mentally and physically. Certainly geocaches tend to be in more beautiful places! I'm not an elitist about the difference - I just found I liked one a lot more than the other. Both have the problem of Found=NotFound reports. There is a bit more of a technical difference with this problem in benchmark hunting than in geocaching. That's possibly where some of the elitiist look gets pinned on benchmark hunting. With geocaching Found=NotFound, people just didn't find the cache and yet convince themselves somehow that their effort equaled a find. With benchmark hunting, the Found=NotFound is generally when someone actually did find a benchmark disk, but it was, for more or less technical reasons, the wrong one, and benchmark hunters want to tell them why because they find the technicality interesting and hope the finder will too.
24. ngs>>gpx

For getting just a county, try this location.