Why would anyone make a light bulb that lasts 3 hours? Is it means to be intermittent duty?


https://www.amazon.com/Speedball-Photo-Emulsion-Flood-004518/dp/B00B02OGQ6/ref=sr_1_32?crid=229TWS5687I9H&keywords=250+watt+light+bulb&qid=1566475527&s=gateway&sprefix=250+watt%2Caps%2C182&sr=8-32

The lamp is a photoflood lamp with a 50V filament. They are designed to produces 3400K for color and B&W photos, at the expense of lifespan: https://www.lighting-gallery.net/gallery/displayimage.php?pos=-87719

Runs continuously?

How many lumens and life at 50 volts?

Your mount carmel lamp could be about 100 watts at 120 volts and produce descent light?

The 230V Philips Photolita, requires 150V to produces 2700K at 1000h and 200W. So at 120V, It should produces a 2300-2500K at 5000h.

Do they sell this bulb still? I want to get some 230 volt photo bulbs and run them on 120 volts.

These lamps are obsolete, since they were use with analog photography, and we are now in digital photography.

All 230 volt bulbs? I can still get the 120s on Amazon.

These lamps are obsolete, since they were use with analog photography, and we are now in digital photography.

There is still many people using film and other analog mediums. Many photographers and artists prefer film for their more natural colors (film is superior for photographing street lights for this reason!  ) and "softer" look with a great wealth of high quality cameras. B&W film offer incredible sharpness and contrast not found in digital photo.  These bulbs are obsolete for the majority, but still serve a purpose and are still manufactured for this reason.

Plus, lighting subjects has nothing to do with film or digital. Good lighting is good lighting no matter how you are capturing the image. Maybe you don't need as much light with digital photography; digital high-ISO can look better than comparable high-ISO films, but that's merely a footnote in my opinion. Incandescent photofloods like the one asked about here have been largely replaced by other light sources, especially strobe lights. Availability of less-costly light sources is the primary reason demand for these lamps has dwindled. (I'm not saying they're bad, by any means! I still use them on occasion).

In practice, they wouldn't be left on for three hours straight. The photographer would turn them on just before taking the shot and then would turn them right back off. Or, if he had a dimmer, he would leave them dimmed to use for modeling, and then bring them up to full brightness just before taking the shot. You can run them continuously; I used to when I started recording video but I went through a lot of lamps! Finally, I switched to proper halogen video lights with better lifespans that I still use today.

But- take a 230 volt 3 hour bulb and run it on 120. good life and good light. I don't ever want to stop using incandescent bulbs and will continue to get creative.   

I have a few of these bulbs around somewhere in my vacuum cleaner collection along with the hand lights they are used in-used for vacuum cleaner demos-show how the clients vacuum is leaking dust.Now A green LED light works-dust shows up well under green light.

Do they sell this bulb still? I want to get some 230 volt photo bulbs and run them on 120 volts.

They come up on (UK) eBay occasionally, I got a few not long ago, an example here. They mainly come in 2 wattages, 275W (P1/1) and 500W (P1/2). The 275W one has a life of 2-3 hours, the 500W is rated at 10 hours. They were originally intended for use in series/parallel circuits, where the photographer would use 2 lamps in series for composing the shot, then switch to parallel for the exposure, thus prolonging the life of the lamps and reducing discomfort for the subject being photographed.

I think it's

I think it's

Nope. Overdriven bulb. Try it with a flashlight one. A two cell bulb in a 3 or 4 cell flashlight. Shorter lifespan than normal. Country of origin has zero influence on lifespan on these things. 50v filament on 120v equals super short lifespan.