Real incandescent streetlighting used rough service long life lamps. Lantern / lamp and its lifetime :
http://streetlightonline.co.uk/eslabulbgone.htmIncandescent conversions of Mercury lanterns - esp. the 80W and 125W sizes (E27 base, widely available lamps...) were pretty common in private property here (Israel) in the past
Actually that aren't really conversions. The common 60s/70s Mercury lanterns are remote gear design. The user would get the lantern alone without the gear box (sold separately), and install it as incandescent
I reckon seeing numerous of those (years ago) in the motel village Ramot Shapira in Beit Meir. See at the far corner of the roof here :
https://upload.wikimedia.org/wikipedia/commons/2/26/Ramot_shapira.jpgThe incandescent on Mercury chokes used to happen in East Germany....
http://www.lighting-gallery.net/gallery/displayimage.php?album=2222&pos=0&pid=60476http://www.lighting-gallery.net/gallery/displayimage.php?album=772&pos=0&pid=81392The ballast output voltage is dependent on the current drawn through it. At low loads (low power incandescent) the voltage would be near the ballast OCV, the higher load, the lower voltage
On 230V (Europe) :
Ballast OCV is 230V, the incndescents are for 230V
If the incandescent lamp is low power (40W..60W), it won't be very different from using it normally. The higher the lamp power, the less voltage it will get, so the more it will be dimmed by the ballast. At some point, you just can't get any more light as if you use higher power lamp it will just be dimmer
You won't be able to get anywhere near the correct light output, no matter what incandescet you use
Lamp life will be longer, esp for the high wattage lamps (as they are underpowered the most)
On autotransformer ballasts (USA) :
Ballast OCV assume on the order of ~300V, assume incandescents rated for 120V
Low power incandescents will get high voltage, so i guess white light for a time between few seconds and few hours. At some point there may be a lamp that loads the ballast just sufficiently to get its output down to 120V, then itll work as any lamp on 120V. Beyond that point it'll be same as in Europe
When the lamp burns out an arc starts in the bulb. Here it is ballasted by a choke, and won't reach the current it takes to blow the stem fuses
On SON / MH gear it will end up in something melting or exploding and a vacuum loss. On Mercury i am not sure - It is possible the same will happen (if the arc stays), and it is possible that the current will be too low to maintain the arc, then it will extinguish on its own (as there is no ignitor to force it to keep arcing)
At very high wattages you might risk drawing too high current through the Mercury ballast and overheting it
It will happen at lamp wattage that is somewhat higher than the ballast current rating. The underpowered lamp takes less current than at full power, but not proportionally to the voltage since the filament resistance is lower when it is underpowered
Assume 80W Mercury lamp at ~0.8A current. 200W 230V incandescent takes ~0.87A. On the ballast that would be down to maybe 0.6 (guessing), so its fine. 300W lamp takes ~1.3A, now that could end up drawing more than 0.8 through the ballast