Using the Projector Arena

The Projector Arena is used for animated targets and can be accessed under the Projector menu on the main ShootOFF window.

While using a projector is highly recommended, you may be able to get away without one if you have a second monitor or TV you can connect your computer to that you don't mind shooting at. Note that it may be difficult to detect shots on some display surfaces -- shiny tends to be fine but some matte surfaces absorb a lot of the laser light (some people have had success covering surfaces that absorb too much light with transparent or translucent paper). If the display suffers greatly from lightbleed it will make detecting shots much harder: turning down the display's brightness can sufficiently mitigate lightbleed. If you would like to buy a projector, we recommend selecting one where the brightness can be configured and whose native resolution is at least 800x600 to ensure the arena has enough space. Smaller resolutions will work too, they just aren't as convenient. At the time of this writing, projectors with resolutions of 800x600 start at about $200. This is quite an investment for dry fire practice: ensure you have another use for the projector (e.g. gaming, watching movies, etc.).

It is significantly harder to use the projector arena with a webcam built into a monitor both because the monitor adds light interference and because it's essentially impossible to get everything lined up correctly. Save yourself a little sanity and don't try to use projector features unless you have an external webcam. On a similar note, do not use a camera that autofocuses or turn the feature off. Projectors, monitors, and autofocus cameras do not mix and you will likely have no luck detecting shots.

To use a projector: point your webcam at the secondary display or projection, ensure the webcam tab that is showing the projection feed is selected, and click Projector -> Start Arena to open the Projector Arena. Opening the arena automatically starts calibration mode. Move the arena to your secondary display (e.g. the projector, monitor, or TV) and hit F11 to put the arena in fullscreen mode. Hitting F11 again or pressing ESC will exit fullscreen mode. In calibration mode shot detection is turned off for the selected feed and a purple region will appear on the open webcam tab's feed, which you should position over the projection the same way you reposition and resize a target. The calibration process is how ShootOFF learns where the arena is and what its bounds are to detect shots on the projection. Hit Projector -> Stop Calibrating to end calibration. You can hit Projector -> Calibrate if you need to calibrate again in the same session.

When calibrating, three options appear at the top of the screen:

• Detect everywhere: continue detecting shots on the entire feed.
• Only detect in projector bounds: do not attempt to detect shots that fall outside of where purple rectangle is when calibration ends.
• Crop feed to projector bounds: this crops frames to the bounds of the purple rectangle as soon as it comes of the camera, thus it is a superset of only detecting in the projector bounds.

We recommend you use one of the latter two options because they allow shot detection filters to tune themselves to the projection area. These settings improve performance by stopping ShootOFF from searching for shots in regions that aren't of interest. You should only use "Detect everywhere" if you need to detect shots outside of the projection.

The basic calibration process is:

1. Ensure your webcam is placed such that the webcam feed on the main ShootOFF window is showing essentially only the secondary display.
2. Ensure the camera and the external display are square with each other.
3. Ensure shots are detected on the secondary display (tweak laser intensity and light conditions until true).
4. Turn on calibration and align the purple region over the projection.

Add targets to the Projector Arena under Projector -> Add Targets and use training protocols as normal. Training protocols that require the projector arena are disabled unless the arena is open. Shoot at the arena on the secondary display or projection.