How is the use of photogates different in Logger Pro 3 from Logger Pro 2?

In Logger Pro 2 the photogates could not be used simultaneously with any other sensors, so we took care of all the necessary setup by providing a special mode in the Data Collection dialog box. Photogate mode was distinct from time-based analog data collection, for example. Once Logger Pro 2 was in photogate timing mode, you could then choose a specific type of photogate collection, such as pulse, gate or motion timing. The appropriate columns would be added to the Data Table. However, it was not always clear how the values were calculated. In Logger Pro 3 we have made the calculations more transparent.

In addition Logger Pro 3 lets you use photogates along with analog sensors. As a result the setup for photogates is more complicated than before. The easiest way to use photogates is to open an experiment file for the particular type of gate experiment planned. If Logger Pro 3 is launched with auto-ID capable photogate(s) attached, the default mode will be motion timing, such as for a picket fence experiment.

In all photogate modes the time column contains the clock times for all gate status changes, or when the gate goes from being unblocked to blocked or blocked to unblocked. From these times, all desired information can be determined. Logger Pro 3 provides a number of functions for calculated columns. For detailed help with those functions, see help on calculated columns. The basic Photogate Timing mode includes only clock time and gate status.

A number of common photogate modes are built into Logger Pro 3 to allow rapid set up for typical experiments. Choosing a mode from the sensor popup menu will create the necessary calculated columns and create their associated graphs. All of the modes can be built from scratch from the basic Photogate Timing mode. The Motion Timing, Gate Timing, and Pendulum Timing modes are analogous to Logger Pro 2 modes of the same name. Photogate Pulse Width gives you the block to block time intervals for a single photogate.

Unlike Logger Pro 2, all of the built-in modes are for a single channel only, since the sensor popup refers only to one channel. If you want to set up a timing mode for photogates in two channels, you must either open an experiment file or add additional calculated columns.

Logger Pro 2 offered a mode called Gate Timing - Two Gates. To obtain this mode, set up both digital channels for Gate Timing and you will have an equivalent mode. Another Logger Pro 2 mode is Pulse Timing. The Logger Pro 3 mode of the same name is for a single gate; to emulate the Logger Pro 2 mode set up both channels for Pulse Timing and modify one of the Pulse columns to determine the block to block time between gates 1 and 2. The Logger Pro 2 mode called Collision Timing can be replicated by setting up both digital channels for Gate Timing. The Logger Pro 2 mode called Gate and Pulse Timing can be replicated by setting up both digital channels for Gate Timing, and adding a calculated column with the function Unblocktoblock between gates 1 and 2.