I have a secret and I will share.  It is done on a digit camera.  I stood there and ever 5 seconds...I would count thousand one, thousand two, and so on until a thousand 5, and then click.  I would keep doing that until the card is full.  I would go back and see if I got anything, and if I did, I would download to the computer and see how it would look.  If I caught nothing, I would delete the card and start over again.  The night I took those, we started getting lightning some 45 minutes before the storm actually moved in on us.  So, I stood hanging out the window taking pictures.  I had 4 good shots that I liked out of probably almost 500.  The arms get tired after a while, but I just rested my arms on the window case.  I was suppose to be studing for a couple of certifications, but that went by the waste side as I worked on getting the pictures taken. 
 
 
Once the storm moved in to close, I stopped, because I didnt want to flood out the bedroom and have an angry wife at me.  That particular storm dumped almost .5 inch of rain, and we had 2 period of hail.  The first period brought .25 inch hail...and the second period brought .25 to .50 inch hail.  The camera was upstairs at that point, and I couldnt get upstairs quick enough to get a couple of pictures of the hail that we got.