TPC 2026 - Survey Calibrations

Managing a Survey's Calibrations

A survey can use any number of calibrations. Once you use a calibration, it is automatically added to the survey and indexed.

As you create calibrations in a survey, TPC adds them to the survey, giving them a calibration index for that survey. TPC may also prompt you to save the calibration to the survey's file folder (default).

CAL Files

The calibration file stores all the information about that calibration in a calibration (.cal) file.

These are the files that show up in the dialogs that allow you to select an existing calibration. When you select an existing calibration to use, you are actually selecting that calibration file. TPC then checks to see if the calibration has already been stored with the survey. If not, it adds it to the survey.

These survey calibrations include the pathname to their .cal files. If the file exists, TPC can use it to report additional information about that calibration. If the file does not exist, TPC can still use the calibration, but can't generate all the associated reports.

If a calibration file has been moved, or it's parent folder or sub-folder names have been changed, you may need to Updating a Calibration's File Location.

Survey (TRV) Files

When you save a survey (create or update it's .trv file), TPC writes abbreviated information about each calibration used in the survey to that file.

This provides information about each calibration for future reference and to help manage the calibration index stored with the survey's data and drawing objects. If you move a survey file to another folder, this calibration information is still available to the survey, so the integrity of the calibrations is maintained.

Managing a Survey's Calibrations

You manage a survey's calibrations in the Manage Survey Calibrations dialog, accessed with the Manage Survey Calibrations command.

•From the TPC Desktop, choose Calibration, Manage Survey Calibrations...

In this dialog, you can

•review the calibrations that have been used by a survey,

•identify any calibrations that are no longer used (no survey objects are currently calibrated by it)

•remove any calibrations that are not currently in use

•edit the properties of any calibration

Adding a Calibration

Adding a calibration through this dialog will allow you to add a calibration to the survey from a calibration file.

Calibrations added this way are indexed to the survey and can then be used to calibrate survey objects like any other survey calibration.

Removing a Calibration

Calibrations can only be removed from a survey if they are no longer being used.

Removing a calibration from the survey does not delete its calibration file. As a result, even though you have removed a calibration from the survey, as long as you haven't also deleted or moved its calibration file, you can still reuse the calibration anytime in the future.

Site Calibrations

If you select a calibration to use as the Site Calibration, this calibration is also stored with the survey's calibrations and receives a calibration index for that survey. See Site Calibrations.

File Compatibility

TPC versions prior to v19.0 (TPC Desktop 2019 R0) do not retain this stored calibration information. If you open and save a v19.0 file in a previous version of TPC, you will loose this data.