Because DART was designed to be super-portable, we made sure that calibration (the process of aligning DART’s camera and projector) was quick and easy. In fact, it will take a lot less time to calibrate your DART system than it will to watch the animated steps below.
DART comes with its own tabletop tripod. Before calibration, attach the removable tripod mount to the bottom of the DART system.
Next attach the tripod mount to the tripod head and lock it down by sliding the locking lever.
In the DART Range software, click Setup and Calibration. You will see a picture-in-a-picture image of what the DART camera sees.
We want to make sure that the DART camera captures the entire picture area of the projector. To do this, loosen the ball-socket screw on the side of the tripod head and move DART until it captures the entire screen.
Its OK to have an inch or so of black border around the edges of the picture. The important part is that the camera see all of the projected image.
Once you are satisfied with the picture, lock the position in by tightening the adjustment screw. When you are ready, click the Next Step button.
DART will project five white circles and a green rectangle on the screen. The rectangle means that calibration is a success. When you see the rectangle, click the Accept Calibration.
Next, DART will do some quick calculations to compensate for the spherical distortion inherent in the round camera and projector lens. This is a very quick process that only requires you to click the Accept Calibration button once you see the green cross on the screen. This will happen five times.
Now that calibration is complete, DART needs to know two last pieces of information in order to draw targets the correct size. First it needs to know the size of the projected image. This is done with the Target Scale slider. Move the slider until the orange graphic in the center of the screen measures one foot across.
Next DART needs to know how far the shooter will be away from the screen. This is done with the Screen Distance slider. Simply move the slider to represent the number of feet the shooter is from the screen.
The last thing to do before you can start training is to insert the lens filter that comes with your DART system. DART uses the brightness of light as seen by the camera to determine what is, and what is not a laser.
Before adding the lens filter, the brightest light detected by the camera is the white areas of the projected image. In this example, the projector light has a value of 252. Anything higher than our default clamp setting of 200 is undesirable.
To reduce the amount of reflected light, drop in the DART lens filter.
Notice that the lens filter knocks down projector and ambient room light to zero (or something very close depending upon your room). Now there is a wide gap between the amount of non-laser room light and our default clamp setting of 200. This virtually eliminates false shots.
That’s it! In actual use, calibration takes less than a minute.
Here is an example of the calibration process occurring in real time.