Webcam putting not picking up putts? Causes and fixes

Last updated 2026-09-30.

Start with what you see. Each section gives the likely cause and the next thing to check. It applies to whichever webcam putting setup you run; PuttBay notes are in their own section at the end. Setting up from scratch? Start with webcam putting for GSPro.

What you see	Section
The tracker never sees the ball	Ball not detected
Short putts work; long ones vanish or come up short	Long and fast putts lost
Fine in the day, flaky at night	Shadows and evening light
The wrong picture, or none at all	Wrong camera opened
Your "60 fps" webcam shows 30	30 fps cameras
The tracker shows the putt; GSPro does nothing	Putter not selected in GSPro
GSPro putts for you	Auto Putt and gimmes
It works, then stops mid-round	USB drops

Ball not detected

Likely causes

The ball doesn't stand out. Color trackers need nothing else in the picture to share the ball's color. cam-putting-py's README recommends a colored ball on a solid, dark surface. Glare or a pale mat can wash a ball out.
The camera changed its own brightness. One golfer's camera would "shift into some kind of auto brightness/exposure setting" and go very dark mid-session (cam-putting-py issue #18).
The ball is too small in the picture. A wide lens from a high ceiling can leave the ball a few pixels across.
The mount moved. A sagging or bumped mount shifts the start area away from where the ball actually sits.

Next check: open your tracker's camera view (in cam-putting-py, the "d" key shows the color mask) with a ball in place. If the ball isn't clearly visible there, fix the light and camera position before touching any settings.

Long and fast putts lost

Likely causes

Not enough pictures. A 40-foot lag leaves the putter at about 10 mph on GSPro (SimGolf's GSPro putting chart, stimp 10). At 30 frames a second it moves about 6 inches between pictures; at 60, about 3.
Too little roll in view. With a foot or two of mat in the picture, a firm putt is gone in a handful of pictures. Aim for 4-5 feet in front of the ball.
Motion blur. In dim light the camera keeps its shutter open longer, and a fast ball smears.

Golfers report exactly this: "working great until I get to long putts or very up hill putts" (issue #19), and a Brio owner who "cannot get the FPS up to 60" saw long putts fall apart (issue #27).

If long putts register but come up short, that's usually the tracker's distance calibration, not detection. GSPro also wants more speed on long putts than you might expect: on the same chart, about 12 mph rolls roughly 53 feet on stimp 10.

Next check: read the frame rate your tracker reports while you putt, then add light and try again.

Shadows and evening light

Likely causes

Your own shadow. Evening light can throw your shadow across the ball's line, and a dark moving shape can swallow a rolling ball. It's the hardest condition in our own bay, too. The cam-putting-py README says the same: don't cast a direct shadow over the ball, and get some light on the ball side.
Settings tuned in daylight. Color settings made in the day can fail at night: "I need to re-calibrate my mask settings often and then again at night" (springbok discussion #122).
Dimmers and window light that change the picture during a putt.

Next check: put a steady lamp over the mat, aimed so your shadow falls away from the ball's path, and hit the same putt again.

Wrong camera opened

Likely causes

Windows numbered your cameras differently. Many trackers pick a camera by number (0, 1, 2). One golfer's tracker opened the laptop's built-in webcam instead of the USB camera, and they noted "Windows seems to arrange the indexes randomly" (springbok issue #117).
Another app has the camera. A video-call app, streaming software or the Windows Camera app can hold it.

Next check: close every other camera app, then pick the camera again. springbok has a Find Video Sources button for this (springbok wiki: Putting). If the number keeps changing, unplug or disable the camera you don't putt with.

30 fps cameras

A camera that really runs at 30 frames a second can't read a lag putt, whatever the settings. But plenty of "60 fps" webcams only show 30:

They reach 60 only at 720p, or only in the compressed MJPEG format. cam-putting-py has an MJPEG option for exactly this.
In dim light they slow down to brighten the picture. Logitech's settings guide mentions "frame rate vs. exposure prioritization."
Another program, or a crowded USB port, is holding them back.

Next check: set 720p, try MJPEG, add light, turn off low-light compensation, and plug straight into the PC. If it still reads 30, treat it as a 30 fps camera for putting. More in choosing a camera.

Putter not selected in GSPro

springbok and similar putting setups send a putt only when GSPro has the putter selected, so a stray roll never becomes a shot. When it isn't, springbok logs "Putting Error: Putter not selected in GSPro, ignoring." (issue #184).

Likely causes

GSPro picked another club. Its club selector recommends a club for where you are, so near the green it can still be holding a wedge.
The putting software missed the club change. In issue #184, the connector said the putter wasn't selected while GSPro had it. A later springbok test build fixed it for those golfers.
The putt never reached the connector. One golfer found a VPN client had taken the port the ball tracker sends putts to, and shared the check: netstat -aon | findstr :8888 (issue #117).
Two connectors. GSPro takes one connected app at a time (why GSPro only takes one connector).

Next check: press U in GSPro to switch straight to the putter (GSPro keyboard shortcuts), check your connector shows the putter too, then putt again.

Auto Putt and gimmes

If GSPro putts for you, or real putting never seems to start in a round, check GSPro's Gimme/Auto Putt match setting. It takes either a gimme distance (2 to 20 feet) or a mode such as Auto-Putt Fixed, Auto-Putt Random or Pick Your Putt (Local Match setup).

Next check: for camera putting, choose a gimme distance. Gimmes are fine. The modes let GSPro handle the putt instead of your stroke.

USB drops

Likely causes

The cable path. A loose plug, an unpowered hub, or a long passive extension.
The camera's USB connection resetting mid-round. It has happened in our own rounds: the camera vanished and only came back minutes later.

Next check: plug the camera straight into a port on the PC, try a different port, and if you need length, use an active USB extension.

PuttBay notes

Ready light: the ball view shows a Ready light you can read from the mat, so you know the ball is armed before you putt.
PUTT AGAIN: if a putt can't be read, the ball view says PUTT AGAIN with the reason, instead of sending GSPro a guess. Re-putt from the same spot.
Camera speed: setup measures what your camera really delivers. 30 fps cameras are refused, with a plain reason.
Ball and light: a normal white ball, no color sliders. A lamp over the mat helps; evening light and shadows are the hardest conditions for PuttBay too.
Putter: PuttBay only sends putts when GSPro has the putter selected, and shows the club GSPro last reported.
Auto Putt: turn it off in GSPro so your real putt counts. Gimmes are fine.

Join the free beta

PuttBay is an independent product and is not affiliated with GSPro, Rapsodo, Garmin, FlightScope or Square.