![]() ![]() In addition to the x and y values, the x and y components of the velocity (Δx/Δt, Δy/Δt) are recorded, where Δt is the time between frames. Now, you have some data that you can analyze. The values of the x and y coordinates of each of the blue points.The x (red) and y (blue) corrdinates plotted vs.It is annoying, but does not change the accuracy of the results. This is a bug in the Mac version of Logger Pro. Notice that these points, the origin, and the scale are offset below and to the right. Are the points representing the center of the blue ball for the first 22 frames.Faint green line is the length scale (in this case, 3 m).The items labeled above are the following:.If you perform the above three operations (and #1 several times), you should get the result below: Simply click to mouse where you want the origin to be. This provides a length scale for the movie. When the mouse is released a dialogue box will open, into which you may type the length of the line. Clicking the mouse at -1 and holding it while moving to 2 will draw a green line across the screen. Keep doing this to record the position of an object (in this case the center of the blue ball) in each frame Pressing button #1 will record the position of the crosshairs when the mouse is clicked and then will avance to the next frame.Now labeled in the Figure above a three important buttons:.Now resize the movie and open the video analysis toolset by clicking on the red dot-dot-dot button in the lower right hand corner of the movie.With LabQuest 3, you can also transfer data wirelessly. Connect LabQuest sensors with an interface to your device, or use LabQuest 3 as a standalone device in the field or on the benchtop. Navigate to the movie and double click on it. With over 80 sensors to choose from, our LabQuest ® family of sensors offers the widest variety of experiments to integrate into your existing curriculum.Insert the movie into your LP session: Menu -> Insert ->Movie.Of course, with your own movies, you can have a little more confidence. ![]() For now, though, be aware that since the frame rate can be changed in a movie, you must be skeptical of the timing of movies obtained from other unknon sources. More instructions will be given upon request. If the frame rate is incorrect, then the movie can be reparsed to correct this problem. When using a movie obtained from another source, then be sure to check that the frame rate properly corresponds to the physical situation being depicted. Therefore, when creating movies, attention should be taken to get the right frame rate. When additional points are added, the velocities of points are calculated, based upon the time elapsed between movie frames and the distance between one point and the next.Įach film clip stores information about the frame rate and LoggerPro reads this in order to determine the elaapsed time between each step. In addition, the point will be placed in a plot that is created at the same time. The program will step through the movie one frame at a time and when a marker is placed on the image in the frame (red dot), the x and y coordinates of point will be entered in the data column, along with a time corresponding to that frame of the movie. Video clips can be downloaded into logger pro for quantitative analysis of position data as a function of time.
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