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You've probably already found one or two benchmarks while doing something else. Now you want to go on your first benchmark hunting trip. Pick about 10 ["PID"]s to look for, preferably fairly close to each other. If you can, pick some that other people have found within the last year or so. This should assure you of a good experience finding benchmarks and prevent you from going home without a find on your first trip. You've probably already found one or two benchmarks while doing something else. Now you want to go on your first benchmark hunting trip. Pick about 10 [[PID]]s to look for, preferably fairly close to each other. If you can, pick some that other people have found within the last year or so. This should assure you of a good experience finding benchmarks and prevent you from going home without a find on your first trip.
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Before going out on your first benchmark hunting trip, be sure to educate yourself on these basic topics: ["designation"], ["PID"], ["azimuth"], ["witness post"], [:to reach:to-reach], ["azimuth mark"], ["reference mark"]. Also look through the list of [:Equipment:benchmark hunting equipment] to get an idea of what to take along. Before going out on your first benchmark hunting trip, be sure to educate yourself on these basic topics: [[designation]], [[PID]], [[azimuth]], [[witness post]], [[to reach|to-reach]], [[azimuth mark]], [[reference mark]]. Also look through the list of [[Equipment|benchmark hunting equipment]] to get an idea of what to take along.
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For every one of the PIDs you've chosen for your hunting trip, print out every page of the ["datasheet"]. Even if you intend to 'go paperless' with your benchmark hunting, it is good to use paper at least on your first trip. On each paper, use a highlighter or other marking method to highlight these things: For every one of the PIDs you've chosen for your hunting trip, print out every page of the [[datasheet]]. Even if you intend to 'go paperless' with your benchmark hunting, it is good to use paper at least on your first trip. On each paper, use a highlighter or other marking method to highlight these things:
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 * Highlight whether the '''horizontal position''' of the PID is ["adjusted"] or ["scaled"]. On an ["NGS"] datasheet, find the horizontal (latitude and longitude) coordinates. They will probably be around the 9th of the lines that start with the PID. After the coordinates will be a word in capital letters - either ADJUSTED or SCALED. On a geocaching datasheet, 2 lines under the coordinates will be the words "location is". After those words, the datasheet will say either ADJUSTED or SCALED. If the mark is horizontally adjusted, its location will be much more accurate than you can measure with your ["GPS"] receiver. If the mark is horizontally scaled, its location will be off by as much as several hundred feet, but is usually within a hundred feet. For horizontally '''scaled''' marks, you can use your GPS receiver to find out about where to park your car. After that, you must rely on the to-reach instructions. Even for horizontally '''adjusted''' marks, the to-reach information often provides better accuracy than your GPS receiver. (Note: very rarely, a mark will say HD_HELD1 or HD_HELD2 instead of ADJUSTED or SCALED, but for benchmark hunting purposes, you can consider these the same as if it said ADJUSTED.) For adjusted PIDs, your GPS receiver should get you to within 15 feet or so of it.
 * Highlight the ["designation"] of the mark. On an NGS datasheet, on about the second line and after the word DESIGNATION, will appear the designation, the official name of the mark. On a geocaching datasheet, the designation line is the 4th line under the coordinates. In case the type of the mark is a disk, you must find a disk with this designation. Finding a disk with a different designation is not a find, even it is in the exact same spot as what you're looking for. If the designation on the datasheet does '''not''' have the word RESET, but the mark you find does have that word, then it is not a find - the mark you're looking for may be gone and replaced by a RESET mark that didn't make it into the NGS database. If what you find says RM1, or RM2, etc., then it is a ["reference mark"], not what you're looking for, and does not count as a find.
 * The most recent [:to reach:to-reach] measurements. Each PID has a section called the recovery section, where each finding report for the PID will have a date. For this highlighting exercise, read these recoveries from most recent to oldest. Find the most recent one that has distances measured from local reference points to the ["station"]. The last distance mentioned is the closest to the mark and is therefore the most important (assuming it still exists). When hunting, you will probably want to look for this last-mentioned reference point first. Highlight these distances and directions. Example: "14 feet SW of power pole 357JX and 3.2 feet East of a manhole cover rim". Occasionally, the very latest recovery note will be missing one or more important pieces of information that hadn't changed. So if you're having trouble finding the mark, review the older recovery notes for any additional information they may have.
 * Highlight whether the '''horizontal position''' of the PID is [[adjusted]] or [[scaled]]. On an [[NGS]] datasheet, find the horizontal (latitude and longitude) coordinates. They will probably be around the 9th of the lines that start with the PID. After the coordinates will be a word in capital letters - either ADJUSTED or SCALED. On a geocaching datasheet, 2 lines under the coordinates will be the words "location is". After those words, the datasheet will say either ADJUSTED or SCALED. If the mark is horizontally adjusted, its location will be much more accurate than you can measure with your [[GPS]] receiver. If the mark is horizontally scaled, its location will be off by as much as several hundred feet, but is usually within a hundred feet. For horizontally '''scaled''' marks, you can use your GPS receiver to find out about where to park your car. After that, you must rely on the to-reach instructions. Even for horizontally '''adjusted''' marks, the to-reach information often provides better accuracy than your GPS receiver. (Note: very rarely, a mark will say HD_HELD1 or HD_HELD2 instead of ADJUSTED or SCALED, but for benchmark hunting purposes, you can consider these the same as if it said ADJUSTED.) For adjusted PIDs, your GPS receiver should get you to within 15 feet or so of it.
 * Highlight the [[designation]] of the mark. On an NGS datasheet, on about the second line and after the word DESIGNATION, will appear the designation, the official name of the mark. On a geocaching datasheet, the designation line is the 4th line under the coordinates. In case the type of the mark is a disk, you must find a disk with this designation. Finding a disk with a different designation is not a find, even it is in the exact same spot as what you're looking for. If the designation on the datasheet does '''not''' have the word RESET, but the mark you find does have that word, then it is not a find - the mark you're looking for may be gone and replaced by a RESET mark that didn't make it into the NGS database. If what you find says RM1, or RM2, etc., then it is a [[reference mark]], not what you're looking for, and does not count as a find.
 * The most recent [[to reach|to-reach]] measurements. Each PID has a section called the recovery section, where each finding report for the PID will have a date. For this highlighting exercise, read these recoveries from most recent to oldest. Find the most recent one that has distances measured from local reference points to the [[station]]. The last distance mentioned is the closest to the mark and is therefore the most important (assuming it still exists). When hunting, you will probably want to look for this last-mentioned reference point first. Highlight these distances and directions. Example: "14 feet SW of power pole 357JX and 3.2 feet East of a manhole cover rim". Occasionally, the very latest recovery note will be missing one or more important pieces of information that hadn't changed. So if you're having trouble finding the mark, review the older recovery notes for any additional information they may have.
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Be ready to take notes. A very important aspect of mark ["recovery"] is to note any changes since the last recovery report and inform the NGS of these changes in your recovery report. Changes in street names, power pole numbers, and changes in which local landmarks should be used and their distance and compass direction '''toward''' the station are examples of things to note in a recovery report. Be ready to take notes. A very important aspect of mark [[recovery]] is to note any changes since the last recovery report and inform the NGS of these changes in your recovery report. Changes in street names, power pole numbers, and changes in which local landmarks should be used and their distance and compass direction '''toward''' the station are examples of things to note in a recovery report.
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In the case of an ["intersection station"], take a picture of the object. Climbing to the top of it is of no value to a recovery report and should not be attempted. In the case of an [[intersection station]], take a picture of the object. Climbing to the top of it is of no value to a recovery report and should not be attempted.
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For other geodetic marks such as disks, rivets, chiseled squares, be sure to take at least two [:photography:pictures] of the mark. One should be a closeup picture of the mark, and the other should be a distant picture '''of''' the mark from a few feet away to show how the mark is seen in relation to surrounding objects. In your report, say which compass direction you were facing when you took this distant picture. An in-between picture, called an eye-level view is sometimes useful as a third kind of picture. These are taken within 10 feet or so of the mark to show how it looks when you walk up to it. Pictures taken '''from''' the mark, without its being in view are of no value to a recovery report. For other geodetic marks such as disks, rivets, chiseled squares, be sure to take at least two [[photography|pictures]] of the mark. One should be a closeup picture of the mark, and the other should be a distant picture '''of''' the mark from a few feet away to show how the mark is seen in relation to surrounding objects. In your report, say which compass direction you were facing when you took this distant picture. An in-between picture, called an eye-level view is sometimes useful as a third kind of picture. These are taken within 10 feet or so of the mark to show how it looks when you walk up to it. Pictures taken '''from''' the mark, without its being in view are of no value to a recovery report.
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In the case of a ["scaled"] mark, use your GPS receiver to get its longitude and latitude coordinates. Use the averaging function if your GPS receiver has one. Noting these coordinates in your ["recovery report"]'s to-reach information will be an improvement over the scaled coordinates. In the case of a [[scaled]] mark, use your GPS receiver to get its longitude and latitude coordinates. Use the averaging function if your GPS receiver has one. Noting these coordinates in your [[recovery report]]'s to-reach information will be an improvement over the scaled coordinates.

You've probably already found one or two benchmarks while doing something else. Now you want to go on your first benchmark hunting trip. Pick about 10 PIDs to look for, preferably fairly close to each other. If you can, pick some that other people have found within the last year or so. This should assure you of a good experience finding benchmarks and prevent you from going home without a find on your first trip.

Before going out on your first benchmark hunting trip, be sure to educate yourself on these basic topics: designation, PID, azimuth, witness post, to-reach, azimuth mark, reference mark. Also look through the list of benchmark hunting equipment to get an idea of what to take along.

For every one of the PIDs you've chosen for your hunting trip, print out every page of the datasheet. Even if you intend to 'go paperless' with your benchmark hunting, it is good to use paper at least on your first trip. On each paper, use a highlighter or other marking method to highlight these things:

  • Highlight whether the horizontal position of the PID is adjusted or scaled. On an NGS datasheet, find the horizontal (latitude and longitude) coordinates. They will probably be around the 9th of the lines that start with the PID. After the coordinates will be a word in capital letters - either ADJUSTED or SCALED. On a geocaching datasheet, 2 lines under the coordinates will be the words "location is". After those words, the datasheet will say either ADJUSTED or SCALED. If the mark is horizontally adjusted, its location will be much more accurate than you can measure with your GPS receiver. If the mark is horizontally scaled, its location will be off by as much as several hundred feet, but is usually within a hundred feet. For horizontally scaled marks, you can use your GPS receiver to find out about where to park your car. After that, you must rely on the to-reach instructions. Even for horizontally adjusted marks, the to-reach information often provides better accuracy than your GPS receiver. (Note: very rarely, a mark will say HD_HELD1 or HD_HELD2 instead of ADJUSTED or SCALED, but for benchmark hunting purposes, you can consider these the same as if it said ADJUSTED.) For adjusted PIDs, your GPS receiver should get you to within 15 feet or so of it.

  • Highlight the designation of the mark. On an NGS datasheet, on about the second line and after the word DESIGNATION, will appear the designation, the official name of the mark. On a geocaching datasheet, the designation line is the 4th line under the coordinates. In case the type of the mark is a disk, you must find a disk with this designation. Finding a disk with a different designation is not a find, even it is in the exact same spot as what you're looking for. If the designation on the datasheet does not have the word RESET, but the mark you find does have that word, then it is not a find - the mark you're looking for may be gone and replaced by a RESET mark that didn't make it into the NGS database. If what you find says RM1, or RM2, etc., then it is a reference mark, not what you're looking for, and does not count as a find.

  • The most recent to-reach measurements. Each PID has a section called the recovery section, where each finding report for the PID will have a date. For this highlighting exercise, read these recoveries from most recent to oldest. Find the most recent one that has distances measured from local reference points to the station. The last distance mentioned is the closest to the mark and is therefore the most important (assuming it still exists). When hunting, you will probably want to look for this last-mentioned reference point first. Highlight these distances and directions. Example: "14 feet SW of power pole 357JX and 3.2 feet East of a manhole cover rim". Occasionally, the very latest recovery note will be missing one or more important pieces of information that hadn't changed. So if you're having trouble finding the mark, review the older recovery notes for any additional information they may have.

These are the most important items in a datasheet. Just before going to each PID's location, review these highlighted items in its datasheet. Making a drawing of what you understand from the geometries of the to-reach statements can sometimes save you a lot of time and false starts.

Be ready to take notes. A very important aspect of mark recovery is to note any changes since the last recovery report and inform the NGS of these changes in your recovery report. Changes in street names, power pole numbers, and changes in which local landmarks should be used and their distance and compass direction toward the station are examples of things to note in a recovery report.

In the case of an intersection station, take a picture of the object. Climbing to the top of it is of no value to a recovery report and should not be attempted.

For other geodetic marks such as disks, rivets, chiseled squares, be sure to take at least two pictures of the mark. One should be a closeup picture of the mark, and the other should be a distant picture of the mark from a few feet away to show how the mark is seen in relation to surrounding objects. In your report, say which compass direction you were facing when you took this distant picture. An in-between picture, called an eye-level view is sometimes useful as a third kind of picture. These are taken within 10 feet or so of the mark to show how it looks when you walk up to it. Pictures taken from the mark, without its being in view are of no value to a recovery report.

In the case of a scaled mark, use your GPS receiver to get its longitude and latitude coordinates. Use the averaging function if your GPS receiver has one. Noting these coordinates in your recovery report's to-reach information will be an improvement over the scaled coordinates.

FirstTime (last edited 2009-03-21 21:03:18 by localhost)