Field Files

Contents

Field File Types
Copan Field File Format

Field Attribute Keys
Remote Elevation Measurement

To Copan, field survey data consist of measured or reduced angles and distances, and come in field files. The field modules — § Field Data Processing, § Field Bearings Processing, and § Field Resections Processing — can read field files.

Note that coordinates — however they've been collected or derived — are not considered to be field data and can only be imported to Copan via the generic import facility (see § Import and Export). If coordinates are in a field file, they will be displayed as comments and will not processed.

1. Field File Types

Copan can read field data in various different file formats. While the files can have any names, certain extensions are advisable:
- Copan field file — .fld or .f*
- Geodimeter file — .job or .raw
- TDS RAW/RW5 file — .raw or .rw5
- Nikon RAW file — .raw
- Leica GSI-8 file — .gsi
- Leica GSI-16 file — .gsi
- Wild GRE file — .gre
Copan does not communicate with total stations themselves, only their downloaded files.
Copan only saves field data in its own format.
Field data files are plain text (or Ascii) so can be edited outside of Copan (but be careful to follow the relevant syntax).
Single-byte character encoding, such as ANSI, DOS or UTF-8 must be used.
Multi-byte character encodings (such as Unicode or UTF-16) will not work.
Note that while both topographic and geodetic variations of Leica GSI-16 data can be read, some manual editing of the loaded data may be required before calculating. This is because GSI files often do not contain setup data (ref. and HI) even though such data are in the instrument!

Let us know ( at support@underhill.ca ) if you'd like Copan to read field data in other formats. Please note the software version and release date (see § Software Version) in all communications.

2. Copan Field File Format

A Copan field file usually consists of numerous Setup and Observation data lines. It may also contain comment lines, as well as Project, Instrument, or Scale data lines, if required.
Each data line consists of various tab-separated attribute-key = value pairs (i.e., a tab character must separate each attribute-key=value pair). Suitable combinations of these attributes depend on the particular situation and are specified in the relevant Field modules chapter.
Spaces may be placed either side of equals signs (e.g., HS = 1.56) if desired.
A Project data line consists of a combination of job, dat, tim, svr, FB, or pgs attributes.
An Instrument data line consists of a combination of instr, VCC, DC, or DF attributes.
A Scale data line consists of SF or UF attributes.
A Setup data line consists of a combination of at, ref/az, HC, or HI attribute-keys.
An Observation data line consists of a combination of to/az, HC, VC, SD, HS, cod, not, nam, dis/bas, or end attribute-keys.
Typically, Observations are indented from Setups for readability, but that is not a requirement.
A valid comment line begins with zero or more spaces or tabs, then has two commas (,,), periods (..), slashes (//), semi-colons (;;), or backslashes (\\), which are followed by any character string. Comments are not processed or stored as point notes (but are saved within the field file). Use them to temporarily remove observations, to make remarks, or to log relevant events.

3. Field Attribute Keys

Here are the currently recognized key words representing attributes in the attribute-key = value pairs. Note that correct case is important.

Attribute key	Attribute meaning	Ignored during calculation
`at`	setup (or occupied) point number
`az`	azimuth (or bearing)
`bas`	base point number for a REM point
`cod`	point (or feature) code
`dat`	date	*
`DC`	distance correction constant
`DF`	distance correction factor (related to PPM)
`dis`	distance point number for a REM point
`end`	previous line is last leg of traverse or last shot of resection
`FB`	field book name or number	*
`HC`	horizontal circle reading (or direction)
`HI`	height of instrument
`HS`	height of signal (reflector, prism, or target)
`instr`	instrument name or number	*
`job`	job/project name or number	*
`not`	point note
`pgs`	field book pages	*
`ref`	reference (or backsight) point number
`SD`	slope distance
`SF`	(combined) scale factor (i.e., projection and elevation factor)
`svr`	surveyor/operator name or number	*
`tim`	time	*
`to`	target (or foresight) point number
`UF`	units conversion factor
`VC`	vertical circle reading (or zenith angle)
`VCC`	vertical circle correction

Let us know ( at support@underhill.ca ) if you'd like Copan to recognize other attributes. Please note the software version and release date (see § Software Version) in all communications.

4. Remote Elevation Measurement

A remote elevation measurement (or REM) is an indirect observation of height and position of a topographic point whose slope distance is unobservable. If you can observe a vertical angle to an otherwise inaccessible point (such as the top of a mast) and you cannot get a reflectorless slope distance, you can determine the 3D coords for that point indirectly, via another point that you can shoot to normally and that is either vertically below the inaccessible point or at the same horizontal distance away.

Let's call the high inaccessible point the REM point, an accessible point vertically below it a base point, or an accessible point at the same horizontal distance away a dist point. To insert a REM observation, reference must be made to either a base point or a dist point:

If referencing a base point
1. Enter the observation via the Observation boxes along the bottom, ensuring the HC and SD boxes are blank. This is often also known as a vertical angle offset observation.
2. Insert the observation, noting that bas= prev is added to the observation automatically.
3. If the previous side-shot is not the base point, edit the prev with the relevant point number, which can be any normally observed side-shot — even one from an earlier or later setup.
If referencing a dist point
1. Enter the observation via the Observation boxes along the bottom, ensuring the SD box is blank.
2. Insert the observation, noting that dis= prev is added to the observation automatically.
3. If the previous side-shot is not the dist point, edit the prev with the relevant point number, which must be from the same setup.
As an alternative, add the observation as usual but use dummy values for SD (and possibly HC). Then edit the line as appropriate. That is, delete the SD= (and possibly HC= ) portions and add the bas= or dis= portion.

updated: 24-Mar-2011