Scale Bar Ratio Map Print Checker (1:500 etc.)
Actual print scale groundmeters×1000/printedmm, comparison to callerintended1:N. Printer/display scaling and ruler uncertainty external; not infer coordinate accuracy.
Description
A printed scale bar relates measured print length to represented ground distance.
A printed scale bar relates measured print length to represented ground distance.1
Comparing its inferred denominator with the intended denominator can reveal a printing-scale discrepancy.
When to use Scale Bar Ratio Map Print Checker (1:500 etc.)
Use this tool to obtain observedPrintedScaleDenominator, signedScaleDenominatorDiscrepancy from the supplied records using the stated calculation. Establish the survey or observation scope, reference frame, units and independently applicable calibration or qualified plan.
How to use Scale Bar Ratio Map Print Checker (1:500 etc.) and understand its results
- Establish the survey or observation scope, reference frame, units and independently applicable calibration or qualified plan.
- Enter actualPrintedScaleBarLengthMm, actualRepresentedScaleBarGroundMeters, callerIntendedScaleDenominator, using the field meanings and rules below, then run the tool.
- Read result.observedPrintedScaleDenominator, result.signedScaleDenominatorDiscrepancy. Use the units and sign conventions below, and review any unknown records separately.
- Correct any reported input issue and run again. Before using a successful result, check the stated units, signs, reference scope and observation coverage.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualPrintedScaleBarLengthMm | Actual printed scale bar length mm | number | Required |
| actualRepresentedScaleBarGroundMeters | Actual represented scale bar ground meters | number | Required |
| callerIntendedScaleDenominator | Caller intended scale denominator | number | Required |
Require positive printed scale-bar length in millimetres, represented ground length in metres and intended denominator. Convert ground metres to millimetres, divide by printed length, then subtract intended denominator. The signed discrepancy is not automatically corrected.
printedDenominator=1000×groundMeters/printedMillimetres; discrepancy=printedDenominator−intendedDenominator Use the matching field units and the exact boundary, ordering and reference rules above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Qualified observed calculation or explicit reference | object |
| result.observedPrintedScaleDenominator | Ground length converted to millimetres divided by printed scale-bar millimetres. | number |
| result.signedScaleDenominatorDiscrepancy | Observed printed denominator minus intended denominator. | number |
{
"input": {
"actualPrintedScaleBarLengthMm": 10,
"actualRepresentedScaleBarGroundMeters": 5,
"callerIntendedScaleDenominator": 500
},
"output": {
"result": {
"observedPrintedScaleDenominator": 500,
"signedScaleDenominatorDiscrepancy": 0
}
}
}Limitations and assumptions
The actual observation coverage, calibration and qualified plan determine applicability. A numerical result does not establish survey accuracy, route suitability, atmosphere conditions or equipment adequacy beyond the declared comparison.
Missing required fields, unknown fields, wrong types and violated rules return input issues. Numeric values and outputs must be finite. Extremely large composite outputs are rejected.
Alternative or Complementary methods
For a related step, use Tape Distance Temperature Correction Calculator: A calibrated measuring tape expands or contracts with its temperature difference from calibration. For a complementary comparison, use Inclinometer Angle True Dip Corrector: An instrument zero offset contributes a signed bias to an indicated inclination.
References
Similar or alternative tools
- Tape Distance Temperature Correction Calculator
A calibrated measuring tape expands or contracts with its temperature difference from calibration.
- Inclinometer Angle True Dip Corrector
An instrument zero offset contributes a signed bias to an indicated inclination.