technique - How do I get proper focus when photographing lightning strikes?

I've been lucky to have the opportunity to photograph several large thunderstorms in Colorado recently, however I ran into a couple issues. The first issue I've run into is getting proper focus.

As a landscape photographer, I've become accustomed to using the hyperfocal setting on my wide-angle lenses, as it makes it easier to get good focus for very distant mountain ranges and the like. I started trying to do the same thing to photograph lightning, however, setting my lens right to the hyperfocal mark does not actually seem to capture the lightning itself in focus. The landscape in the distance behind seems to be in focus, but it seems to be a bit too far out otherwise.

Most of the time these thunderstorms happen late at night, and it is nearly pitch black except for the light from lightning itself. Are there any tricks I can use to quickly focus properly so I can capture lightning without it looking like chains of bright white bubbles? I've tried a trial and error approach, however I've ended up missing many really great shots because I was fiddling with my camera trying to get it in proper focus. Even slightly out of focus, I wish I had been able to get some of the shots I missed.

Lightning Focus http://a.imageshack.us/img412/8115/lightningfocusexample.jpg

Above is the best ground strike shot from a set taken a few days ago. You can best see the lack of focus in the non-main streamers. This was a smaller bolt, struck probably less than 500 feet away. The tree in the foreground, probably about 10 feet from the camera, is also a bit out of focus. I had originally tried to focus on the landscape well behind near hyperfocal focus...at least, as best I could tell in the dark. I made several adjustments successively through numerous shots to finally get this shot as clear as it was. I missed plenty of much better shots, however, due to the lack of focus. If there was some quick trick to set a correct focus in near darkness, I'd LOVE to know about it.

Answer

I'm writing down some of the ideas that are scattered here and there:

• Hang something heavy below your tripod to minimize wind (and possibly shockwave) shake


• Check whether you can trust your focusing scale for manual focusing (see my comment below Guffa's answer)


• Stop down your aperture as much as you can (you probably want to stay in the 30 sec AE limit so it might not be applicable)


• If possible check whether something is in focus in your picture to understand where the focus was set. It's really easy to loose focus by accidentally touching the focus ring (sorry if it sounds too obvious, just I've lost more shots I'd like this way myself).