Stopwatches

Because of the difficulty and cost of using an automated timing system, the basic method of timing for Head races is to use a stopwatch. This can be moderately accurate with the correct procedure, but is not quick.

Precision

A hand timing system can give an acceptable level of precision. Hand timing is always used for backup in International Athletics competition, and may be used to establish records. Good technique from the timekeeper can give a precision of about a tenth of a second.

Accuracy

A normal stopwatch will gain or lose time over the duration of the race (see Clocks). So times taken close together will be accurate in relation to each other, but times taken at the beginning and end will be less so. However this may be acceptable, since: competitors racing each other in a category will usually start close together; and competitors racing at different times will anyway be subject to different wind and water conditions.

Rounding

When using hand timing, sports like Cycling and Athletics round the times to reflect the degree of precision of the timer and the accuracy of the watch. For example, times for Cycling time trials are rounded down to the nearest second. Times for the marathon are rounded up to the nearest second.

Output

The main problem with a normal stopwatch is the lack of electronic output. Times taken are displayed and stored, and may be written down. Only after the race can they be exported. This creates a logistical problem.

Writing the times down is surprisingly difficult when several competitors finish close together. It can be done, but requires skill and experience. It is easy to miss times, or to write them down incorrectly or illegibly.

Because it is easy to miss times or make a mistake when writing them down, a second timer is needed. With a second timer it is hard to say who is right and who is wrong, so a third timer is needed. Now there are three sets of times, all of which may have errors.

After the race the times need to be put into a spreadsheet. Typing them in can introduce additional errors. It is better to upload the times from the stopwatches to avoid this. The uploaded times then need to be matched with the written boat number. All the times need to be compared to find and resolve discrepancies.

This takes a lot of time. To reduce the delay, the timekeeper may take one set of times as a master and only take missing times from another timer. But times taken from a different timer will have a different reaction time, and competition rules do not normally allow this without compensating for it. The master times may also contain errors (for example identifying the wrong boat), which will not be known till all the times have been compared.

Since writing the times down introduces error, the timekeeper could dispense with it and only upload times after the race. A note needs to be made of the boat number corresponding to the button press (a Memory number); and then boat numbers are matched to times after the race.

This introduces the risk that the times may be lost altogether if there is a problem with the stopwatch. However this should be extremely unlikely. If the watch is stopped the times are retained in memory and available when it is switched on. How could it actually happen:

  • accidentally press and hold the Clear button
  • open the battery compartment, or lose battery power
  • physical loss or damage to the watch.

Conclusion

The stopwatch method is an acceptable method of timing a Head race, but only with a tightly defined procedure. This should require:

  1. Rounding up to the nearest full second OR
  2. All competitors in one category start within a few minutes i.e. no split categories, and no overall pennant
  3. Timing data uploaded from the stopwatch after the race, not written down or typed in
  4. One primary timer, one backup timer and one last-resort video
  5. An averaging procedure for inserting missing times into the primary times.

Types of stopwatch

The requirements of a stopwatch for Head race timing are:

  1. Good accuracy. The accuracy should be specified, or better still certified.
  2. Sufficient memory to store the times of competitors, at least per category or per division.
  3. Data export.
  4. Waterproof and easy to use with cold hands or with gloves.
  5. Ideally (but none have this) a case or a lock to prevent accidental button presses.
 
Make Model Accuracy Memory Export
Accusplit AX602 0.24 seconds per day at 70°F 500 No
Control Company Traceable 1031 0.0005% temperature range not specified 500 No
Fastime 26 Not specified 500 Yes
NK Interval 2000 Not specified 2000 Yes
Seiko S141 or S143 0.0006% at normal temperature range (5°C - 35°C) (41°F - 95°F) 300 Yes
TAG-Heuer HL400 0.0007% temperature range not specified 800 Yes
Ultrak 499 Not specified 2000 Yes

Of these, the TAG-Heuer most closely meets the requirement. The Seiko has a very impressive accuracy specification but only 300 stored times. This will be enough for many races. The NK and Ultrak have enough memory to time larger events, but do not specify an accuracy. The NK is waterproof and familiar to many rowing people, and so might be preferred if sub-second accuracy is not required.

The NK Interval 2000 stopwatch has a cradle with RS232 serial interface, and a software application Interval Watchware for Windows. The software works under Windows XP, but it does not install or run under Windows Vista or Windows 7. I have a virtualised copy of the Interval Watchware for Windows software that works on Windows 7. This saves you having to find an old XP laptop for the upload. If you would like a copy of the virtualised software please contact me.