Not bad. They look a lot like my very first attempts to catch lightning, and by pretty much the same method. :thumbup:
The last one is the best. It needs a bit of post processing though, I think. First, I'd correct the distortion/perspective, stretching the top wider until the vertical lines are at least nearly straight, if not all the way straight. Next, I'd reduce the exposure just a tad, at least on the sky area - that said, it looks like you could be shooting your 30 second shots with a smaller aperture for a better exposure. I see you were at f/4. Try f/5.6 or even f/8 - the lightning, when it happens, will still light up your shot, and the images will be a little sharper right out of the gate stopped down a little. Speaking of which, finally, sharpen it up a bit in post.
One of the things you're doing right, in my opinion, is including a foreground. The apartment buildings aren't a terribly exciting foreground, admittedly, but they're better than nothing - lightning in the sky with nothing else in the composition is usually really not exciting at all - there's no context for the lightning. As to the overall composition though, you've got to get set up so you don't have that wall and overhang on your side of the road still in the shot, if at all possible.
I see you were shooting at 24mm. On your crop frame sensor, that's the equivalent of about 35mm. That's not bad, but if you can get even more sky with a wider lens, that would be great. Lots of folks start out with a kit lens that goes down to 18mm. The 10-22mm range of lenses is also popular (I love mine). If you have one of those wider lenses, or can borrow one, try that instead - get as much of the sky as you can, while including a foreground for context, and you've got the best shot at getting a real "keeper". You can then crop down to the best composition later in post production, depending on where in that big sky the lightning decided to show up.
On the focus issue, that can be kind of tough. It's mostly dark, you're aimed at a dark sky that you can't focus on, so you crank your lens to infinity and hope for the best. Problems with that method are, first of all, many newer lenses actually go past infinity, so you're not at your sharpest if you do that.
Here's another idea that flies right past those problems: Look into hyperfocal distancing. These links can help you understand how to do it, and provide a calculator to help with it:
Hyperfocal Distance and
Hyperfocal Distance Online Depth of Field Calculator. You can set up before hand with something measured and locked into your focus in a nice, well lit, dry environment indoors to get a focus lock at a precise distance from your focal plane on the camera per the calculator, which will give you sharp focus from somewhere just in front of you ALL THE WAY to infinity - automatically. Then make sure you shut of AF if you have it on. Once you have that focus and aperture locked in, you can put little sharpie marks or pencil marks or crayon marks or stick a couple little dots on your lens to show where the focus ring needs to be lined up, then you can line them up easily on location with a flashlight, and you're in business on the focus, no fuss, no muss.
A rain sleeve is a good idea, and there are good, cheap ones out there, as well as the expensive, awesome ones. I keep a couple of these in all my bags, the glove box, pretty much everywhere:
Amazon.com: OP/TECH USA 9001142 Rainsleeve-Flash, 14 Inch Protective Cover for Camera and Flash: Camera & Photo They come 2 per bag, which makes them about $4 each. In a pinch, before I got them, I had no problem using a plastic bag, even a garbage bag, with a hole in it for the lens, then just rubber band it in place and be sure to use the lens hood to help keep the drops off the front element. The thing about these clear bags made for it though is that you'll be able to make sure your hyperfocal setting marks can be seen and set even with the bag on.
Last, but most important: Be careful. It goes without saying that lightning is dangerous stuff. Don't forget that part!
Have fun with it! You'll get better shots with more practice! :thumbup:
