Photo Finish Cameras Explained: How FinishLynx Works for Athletics, Cycling and Skating

It is not a high-speed camera. It is a line-scan camera.

The most common misconception is that a photo finish camera takes a very fast burst of normal photos. It does not. It captures a single vertical line of pixels at the finish-line plane, repeatedly, at up to 20,000 lines per second. Each captured 'line' is stitched horizontally as time progresses, producing an image where the X axis is time and the Y axis is lane / position.

That is why a photo finish image looks slightly stretched or compressed — the geometry along the time axis depends on how fast the athletes were moving and the line-scan rate.

Sync to the gun

For the result to be official, the camera must start counting at the instant the starter's gun fires. This is done with a hard-wired or wireless start sensor (Lynx Start System, ReacTime, AlgeTime), so the time axis on the captured image is anchored to T=0. Any clock drift between the start and finish is corrected with a sub-microsecond reference, and times are read to 1/1000 second then rounded per the rulebook.

Why FinishLynx dominates

FinishLynx (Lynx System Developers, Haverhill, MA) is approved by World Athletics, UCI (cycling), ISU (speed skating) and many horse-racing jurisdictions. The EtherLynx Vision PRO line is the high-end (up to 20,000 fps line rate, full colour), with Vision PIC and the more budget-friendly Vision and ProChip for lower tiers. The same evaluation software (FinishLynx capture) is used across all of them, which means an experienced chief judge can move between meets without retraining.

What you need around the camera

• Mounting platform aligned within 1° of the finish-line plane, typically on a gantry or scaffold tower
• Gigabit Ethernet from camera to capture PC
• Start sensor (gun mic / start block sensor) for the time anchor
• Evaluation workstation with FinishLynx, multiple displays for chief judge and assistant
• Result publishing pipeline — Lynx ResulTV, NDI feed to broadcast, RaceResults / Meet Manager interface to the results database

When you do, and don't, need one

Any race where two or more athletes can plausibly cross within 1/100 of a second needs a photo finish camera if the time is to be official. That covers athletics sprints, cycling track and road, speed skating, horse racing, and rowing (where a side-on photo finish is also used). Marathons and longer road races still benefit from a photo finish for the elite finish even when chip timing covers the rest of the field.