Question - 650w bulb on a 1K light?

Natalie Saito · May 27, 2007

this may be a dumb question, but i'll just ask it... could you place a 650w bulb on a 1K light? i was wondering if it were possible to switch b/t 650 watt and 1000 watt bulbs on the same lights. i'm considering on getting a 1K kit. thanks for reading!

Natalie

Jonathan Bowerbank · May 27, 2007

Ummm, what specific lights? I suppose you're referring to the Arri fresnels that are so common. I would assume not, since I believe the fixtures themselves are physically larger or smaller (correct me if I'm wrong)

On the other hand, Photoflex's "starlite" accepts both 500w & 1k bulbs.

Rick Sharf · May 27, 2007

I would say yes it would be a problem if you were trying to put a 1k bulb in a 650 source, but stepping down is not such an issue i dont think as long as the bulb fits. Is there any reason you cant get both a baby and a tweenie?

Alessandro Machi · May 27, 2007

Basically you can as long as the same bulb manufacturer makes a smaller wattage version for that series of light. For instance, I bought what I thought would be a useful light because it ran off of dc power and it had a swing in/out dichroic filter already attached. The problem has now become that the FAV bulb that goes into the light seems to only come in one wattage size (100W / 11.5v), only has a bulb life of 6 hours and is discontinued! I was assuming I would be able to find a 50W or 60W version of this DC bulb but one was never made so I may end up having the socket changed out to something more common.

I think it's a good move to put a bulb in that best matches the type of shooting that you may be doing the most. The primary problem that can come up is when you just want an overall bounce effect and the lower wattage bulb is just not enough, or you need to daylight balance the light and will probably need more than a 600-650 to begin with. I think what you are doing is a good move because it reduces the overall amount of heat being generated and frees up more current for other lights.

Sing Lo · May 28, 2007

The answer is no if the light is a 1K fresnel. You can only put a 750W or 500W (only in the USA) on a 1K fresnel . 650W fresnel has different lamp base as 1K. On the other hand, you can put a 300W on a 650W.

timHealy · June 1, 2007

You don't mention the specifics of what type of 1k you are using.

But as long as the 650 watt bulb (or any wattage lower than what the lamp was made for) has the same base or connector as your 1k bulb and physically it can fit, you can do that. But if the bulb itself, aside from the base is a different shape or length than originally intended, you may find the optics a bit off if on a fresnel.

Best

Tim

Edited June 1, 2007 by timHealy

Natalie Saito · June 2, 2007

yeah I meant the 1K tungsten (arri). thanks a bunch.

JD Hartman · June 2, 2007

Instead of buying lower wattage globes for your 1K, just drop in a scrim, or two. Or put some ND on the barndoors. If you start buying globes in multiple wattages for the same head, before you know it, you have a spent a large sum of money on spares. Money that could be used for gels, grip equipment, other lights, etc.

Matt Sandstrom · June 2, 2007

yeah, or use a dimmer. the only reason i see to use lower wattage bulbs would be if you need to use three lights on one household breaker or a 2k honda. i like 650w lights for that reason.

/matt

Natalie Saito · June 3, 2007

yeah, or use a dimmer. the only reason i see to use lower wattage bulbs would be if you need to use three lights on one household breaker or a 2k honda. i like 650w lights for that reason.

/matt

thanks matt. that may be the solution. my question is not about controlling/or reducing light..its about saving amps or power for other sources. are dimmers brand-specific? i'm getting arri lights. i can't seem to find a mixed kit with both 650 and 1k which is what i wanted. if you buy them separating (w/ stands, accessories) is much more expensive.

650s are good but 1ks are more powerful. hmis are more expensive. speaking of hmis, do they use the same amount of amps (or more) as tungsten?? im referring to the ballast.

thanks guys!

Sing Lo · June 4, 2007

thanks matt. that may be the solution. my question is not about controlling/or reducing light..its about saving amps or power for other sources. are dimmers brand-specific? i'm getting arri lights. i can't seem to find a mixed kit with both 650 and 1k which is what i wanted. if you buy them separating (w/ stands, accessories) is much more expensive.

650s are good but 1ks are more powerful. hmis are more expensive. speaking of hmis, do they use the same amount of amps (or more) as tungsten?? im referring to the ballast.

thanks guys!

A 575W HMI fresnel would take less power than a 650W tungsten and would be about 2-3 times as bright, but cost several times the price. If you stick a full CTB gel to a 1K Arri, you will get daylight. You can still get usable power from the Arri 1kW despite the loss of 2 stops from the CTB. That's poorman's alterenative to HMI.

timHealy · June 4, 2007

Sometimes HMI amperage may vary from the rating due to variables like age of the equipment and bulbs. Tungsten is much more straight foward.

Best

Tim

Dan Goulder · June 4, 2007

yeah I meant the 1K tungsten (arri). thanks a bunch.

You can use a 750W or 1000W with an Arri 1K Fresnel. I believe those are your only two choices with this particular fixture.

If it's a 1K focusing flood Arri, then I think your choices are 1000W or 600W.

Alessandro Machi · June 4, 2007

yeah, or use a dimmer. the only reason i see to use lower wattage bulbs would be if you need to use three lights on one household breaker or a 2k honda. i like 650w lights for that reason.

/matt

I think the amount of heat being generated is a concern, unless one lives in a colder region of the world and the warmth being generated is actually a good thing. If you actually have a make up and hair person that actually stays for the whole shoot than the warmer temperature a bit less of an issue.

The problem with using (3) 650's on one circuit is it still is pretty close to a 2k threshold, I've found that going over 1,750 to 1,800 can cause the circuit breaker to activate. Does the length and guage of line affect the draw of current? If the resistance increases as the length of cable run increases, is it possible that a 650 light will draw more than 650W to make up for resistance in the line, or will the light just not be as bright, or both?

Matt Sandstrom · June 4, 2007

If the resistance increases as the length of cable run increases, is it possible that a 650 light will draw more than 650W to make up for resistance in the line, or will the light just not be as bright, or both?

you need a lot of cable to see a difference, but if you do yes it will be less bright. both because some of the effect will be taken out as heat in the cable, and because the amperage may actually drop due to the increased resistance. compare with two lights in series versus in parallel.

/matt