Measuring Rocket Speed from Video

   To measure your rocket's speed and acceleration from a video, it is
necessary to have the video camera on a tripod and back far enough where it
will view the launch for 100 feet up and also close enough to get clear
measurements. It must also not have image stabilization.
 The Target and Ritz Camera pocket camcorder. 
   This particular camera, which has also been inside a chemical rocket, has
no tripod socket, so we lean it on the car where the wipers recede facing the
launch pad.  It has a swing-out USB connector and a videocam-to-TV jack.
   WARNING: It will simply shut itself off if you wait too long after turning
it on before you start taking a video.
   Connect the camera to a computer, which will detect it and then open the
software aleady in the camera. Click on any choice, but it's best to save the
video to a folder and then delete it from the camcorder.
   You will also need a program that can extract single frames from a video.
We use two (free) DVDVideoSoft programs, one to edit videos and one to extract
frames. If you do download it, click on Free Video to .JPG Converter, Extract
Images From Video, Continue, Every Frame, select an Input file (point to the
folder where you saved the video), Open, select an Output folder (where you
want the extracted images stored), Save (NOT Snapshot!), OK.
(NOTE: Snapshot may or may not save the actual image you are viewing!)
   All of the video's images will be in the output folder. Use any photo
software to view them in thumbnails.  Find the images from the launch until
the rocket is out of sight and print those in 8 x 10 format.  You can then
delete the image frames folder.
   Put the printed images in order and measure from the bottom edge of the
image to the tip of the nose cone in 1/32".  For instance, if it is 3 & 3/4",
that's 120/32".  Write both of those in the white border.
   Measure the length of your rocket in feet and convert it to decimals.  If
your rocket is 43 & 3/8" long, that's 3.6 feet.  Now determine the scale.
   Measure the length of the rocket image in the clearest frame. Suppose it's
5/8" long (20/32").  The scale is 20/32" divided by 3.6 feet, or each 1/32
inch equals .1736 feet. Write these on the border.
   Now measure each image from the bottom edge of the image to the tip of the
nose cone and write it on the border.  Convert each measurement to 1/32 inches
and write it on the border.
   Now subtract the distances from one frame to the next and write the
difference in 1/32" on a note pad.  This is the distance gone in 1/30 second.
   Now convert those differences in 1/32" to feet by multiplying by your
scale, such as .1736 feet was in this example.  (But use your actual scale.)
   Multiply each difference in feet by 30 to convert it from feet per 1/30 of
a second to feet per second.
   Multiply each ft/sec by .6818 to covert it into miles per hour.
   You can convert two different speed readings into acceleration.  Subtract
the feet per second readings from one line on your note pad to the next. This
is the CHANGE in speed from one 1/30 sec. to the next, so multiply this by 30
to get the speed change per second (acceleration).  Compare this to gravity,
32 ft/sec per second, or to other rockets.