User`s guide

Measurements

Calibrating Videotaped Images for Measurement

9-22 Revision D.0

Calibrating Videotaped Images for Measurement

These steps pertain to any images that have been videotaped, even if you are

viewing those images in Loop mode or Disk mode.

1. Press .

2. Press .

3. Use the trackball to select the mode, and then press .

4. Place the measurement caliper on a marker according to the mode, as

indicated on the screen, and then press .

5. Move the caliper to another marker of the same kind. Place the second caliper

as far away as possible from the first marker, and then press .

NOTE For time measurements, be sure the second caliper is to the right of the first

caliper. If it is not, the calculated mean values will be incorrect.

When reviewing the results of measurements made from videotape, if the

maximum and mean gradients are the same value, the calibration was done

incorrectly. Recalibrate the image as described in this section.

6. Enter the corresponding value indicated between the two points, and then

press . Follow any additional instructions that are displayed for this

mode.

NOTE When entering Doppler values, it is important to be sensitive to numeric signs.

When entering a velocity value, if the value is negative, be sure to enter a

negative sign with the value.

7. When you finish a measurement, press . The system displays a

“Calibration complete” message.

Freeze

Caliper

Enter