Those bug trails from the long exposure look like the beam is sending out lighting bolts to the surrounding air

I kind of like this effect, it shows life in our atmosphere (that would be death if the beam was slightly more powerful though...)

That is incredible, all that with just 200W! This is something I would expect from a 1000W halide, but no. Very interesting setup, nice color as well

UHP (mercury) lamps are particularly effective at producing narrow beams due to their extremely small (1.0 mm) and bright (>1Gcd/m2) arc, characteristics that metal halide lamps cannot touch. This is because mercury plasmas tolerate much higher power loads than metal halide ones. Moreover, the mercury arc's luminous distribution is much narrower with a more even color. All that enables a way more effective optical control of the emitted light. Interestingly, in the present case I used an early UHP lamp (late 1990s) that does not even have the most efficient optical design.

The 200 W lamp used here is fitted with a parabolic mirror that enables a direct collimation of the emitted light, but this results also in a lot of light spillage, that's why we can see three parts in its beam structure: the main collimated channel, some wider surrounding beam, and the broad light spill. A better optical design, which came later, involves an elliptical mirror which collects more of the light emitted by the arc. However, secondary optics, such as a condenser lens, is then needed to collimate the light into a narrow beam. That's what became standard in pin spots. Interestingly, pin spots do use UHP-like lamps with metal halide additives in order to improve the light color quality, but this comes at the cost of brightness and efficiency. A pure mercury (UHP) 200+ W pin spot with optimized optics should look even more impressive than the projector shown here.