I have wondered for the longest time if any other materials besides tungsten and carbon were used for incandescent bulb filaments. I have heard on different online resources of using tantalum for a light in the ~3000k range and osmium instead of tungsten, but can anyone verify this? TIA.

I have wondered for the longest time if any other materials besides tungsten and carbon were used for incandescent bulb filaments. I have heard on different online resources of using tantalum for a light in the ~3000k range and osmium instead of tungsten, but can anyone verify this? TIA.

I have also heard of bamboo being used. I wonder how that worked?

Zarlog, bamboo was shaped and put into the oven and heated to the point which the molecules that compose it begin to carboniz. Can confirm, I did a project over Edison in middle skool.

Nernest lamps used ceramic filament, but required a heater since ceramic filament only conduct at high temperatures.

Technically carbon is not metal, so rigorously speaking not a subject of this thread :-)
For main base metals I know about the Platinum, Tungsten, plus some experiments with Osmium (but don't know if it was ever used alone, or just as a dopant for and/or alloy with the Tungsten)

Regarding non-metallic filaments, Nernst lamps have used some sort of ceramic material and in the era of the first experiments with incandescents (when these were just a novelty gadgets and not yet any practical light source) the experiments included even iron or similar materials.

Bamboo in the oven is indeed just a way to prepare the carbon filament. By the way the modern production methods (not anymore for the lamps, but for the structural fabrics in laminates,...) are not that different - a cloth made of is heated till it carbonizes. It only involves plastics instead of the bamboo as the precursor materials.