Yes. Sadly I must agree a DSLR is the way to go. A film camera will work fine, either 35mm or 2.25", but at $1.50 per click on medium format film, that can pay for a DSLR real fast.
I have a Canon Rebel T5, new with kit lens it's $400. Used for $300. Love it. (Don't tell my Bronica!)
On 90% of sparks I'll shoot ISO100, and wish it had an ISO25. On distant sparks or 'dim' anvil crawlers, I'd go to 400-800ISO. But DSLRs seem more sensitive to low light, so I like the ISO100. The F-stop I have at F5.6. Most all the time. If the sparks are close and bright, perhaps an F8 will do. If going for the broadcast antenna at 300 yds, perhaps an F11.
Bulb setting is really helpful, and so a remote trigger needed. This is where the shutter is just open for as long as you choose. 10sec to 4 min, but I've found DSLR will wash the sky out on long exposures. About 60 seconds if any town lights is max. Also for safety, as you can be inside your Faraday Cage and still shoot. Also one can try a 'reaction time shot'. Where you just set the exposure for a nice picture without the lightning. Dial it in on manual. Usually leaving it at F5.6 and adjusting the exposure time to get it looking good. Then you have to be real quick. No it's not impossible. Lightning can last from near instant single stroke, which you'll never catch except by accident, to as long as 1.5-2 seconds! Even a drunk person can catch these. And often they're real cool shots.
A tripod is a must. A sturdy one.
And lastly. On reaction time shots. If your exposure is 1/60th sec or faster, it's quite possible to take the picture in between return strokes. You'll think you nailed it. You had fast reactions. You heard the mirror flap right during the bolt! But... nothing. The individual return strokes are very fast. Like < 1 millisec? So you really need an exposure of 1/30th sec or longer. Even if you have to push the fstop up.