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>Light Bulb For Mini Brute

Published : 31st August 2006

I need to buy some par 34 for my mini brute lighting package but is struggling to find any.

I'm trying to find out what voltage a bulb in a mini brute light actually has.

This would be for the UK which is 220-240v and the answer seems obvious, but that turns out to be a hard find.

I can only come across 110v, is there something I'm missing?

I've asked around but no-one (strangely enough) knows off hand.

Cheers
Flemming Jetmar
DP London


class="style11">>I can only come across 110v, is there something I'm missing?

class="style11">>I've asked around but no-one (strangely enough) knows off hand.

Check the wiring of the lamp holders as they may be wired in series so 2 x 110V lamps would work on 220/240V

Alternatively contact me off list and with the spec of the lamps and I'll see if I can source any from my lamp wholesaler.

Peter Daffarn


I think Mini-Brutes take a 650w Par 36 lamp. They're usually 110v and wired in series pairs. I would try www.bltdirect.co.uk.

They seems to have a very wide range available.

Stuart Brereton
DP, UK


Yes of course, they are serial paired 2 x 110 = 220, silly me.

Thanks

Flemming Jetmar
DP London


class="style11">>Yes of course, they are serial paired 2 x 110 = 220, silly me.

So if one goes out, than another will blow out as well, right?

Jim Sofranko
NY/DP


class="style11">>>Yes of course, they are serial paired 2 x 110 = 220, silly me.

class="style11">>So if one goes out, than another will blow out as well, right?

No, if one blows, the other "goes" out. The second bulb doesn't actually blow. Replacing the ONE bulb will bring the PAIR back to life.

Same setup as MoleFAYs in Australia. These take FAY bulbs which are 120 volt 650w Par 36 with a dichroic coating, giving roughly daylight without gelling. There's never been a 240 volt equivalent.

[240v filaments have to be longer than their 120v brothers and this often isn't possible in some types of lamps - particularly ones that rely on short linear filaments to get the right focus in small parabolic reflectors.]

Clive Woodward,
Nine-bulb MoleFAYs aren't too practical down here
Perth, Western Australia.


Jim Sofranko wrote :

class="style11">>>"So if one goes out, than another will blow out as well, right?"

Well, no. In a series circuit if one bulb blows out the circuit opens and current stops flowing through it, both lamps will go out but only one is faulty. Find the faulty lamp, replace it and both lamps are ready to burn.

Victor Lefelman
Gaffer


All the FAY lights (mini-brutes) I have used in Europe were set up with even numbers of globes and wired in series pairs, and used the same globes we use in they US I only ever used white globes (ANSI code FCX) not the blue FAY globes,)

I am pretty sure this was true in India also, though that was a LONG time ago. From memory, I believe that the two globes you can still find for these fixtures are FCX (650w. medium spread) and FCZ 650w. wide spread)

Mark Weingartner
LA based VFX
erstwhile gaffer


Clive Woodward writes :

class="style11">>[240v filaments have to be longer than their 120v brothers and this often >isn't possible in some types of lamps – particularly ones that rely on >short linear filaments to get the right focus in small parabolic reflectors

The 110V filaments are also much stouter and can achieve a greater output efficiency.

As far as running a 9 lamp unit on 240 goes... Isn't that an 8 lamp unit with a special storage position for a spare lamp?

Clive Mitchell
http://www.bigclive.com


My old mini brutes take lamps in pairs (a serial connection of 2 X 110V).

So there is a chance that 220V lamps did never exist.

By the way :

I bought mine as part of a used package 4 years ago and never thought of using them. Do they give a punch? I expected them to be energy inefficient.

Am I right or wrong?

Regards

Argyris Theos
DoP
Athens Greece


class="style11">> By the way :

class="style11">>I bought mine as part of a used package 4 years ago and never thought >of using them. Do they give a punch? I expected them to be energy >inefficient. Am I right or wrong?

Quite the contrary. IMHO Minis and Maxis, and any PAR type based fixture, is usually the most efficient light output per watt. The filament is surrounded by reflector and no light goes anywhere but out front where you want it. Now is it nice light quality...well that depends how one uses it.

I love 9 light mini-brutes. I rarely shoot without a few. Light enough to be handled by one person and easy to rig in tight spots, maxis are way heavier and more difficult to handle. Used bounced or trough larges frames most of the time, if there is too much, just flick off a few bulbs.

Try one out...you'll like it

Daniel Villeneuve, c.s.c.
Directeur-Photo / Director of Photography
Montréal, Canada
Demos: www.dvdp.ca


Thanks Daniel, I will

Argyris Theos
DP
Athens Greece


Victor Lefelman writes:

class="style11">>>In a series circuit if one bulb blows out the circuit opens and current >stops flowing through it, both lamps will go out but only one is faulty.

Right. In effect you've replaced two lamps for the price of one!

Note that, all else being equal, 110-120-volt lamps have thicker, stronger filaments, and more light output per watt, than 220-240v lamps (because light output is a function of current), so that's an additional advantage.

Dan Drasin
Producer/DP
Marin County, CA


class="style11">>Note that, all else being equal, 110-120-volt lamps have thicker, >stronger filaments,

Okay up to this point

class="style11">>and more light output per watt, than 220-240v lamps (because light >output is a function of current),

No, no, no!

[reviewing rules-of-physics-101]

Light output is a function of POWER. Power is voltage times current. A 110 volt, 1Kw bulb outputs the same amount of light as a 240 volt 1Kw bulb.

Why do lighting people refer to their lights by wattage rather than current?

[Of course I'm comparing apples with apples - tungsten filament bulbs in this instance.]

Clive Woodward,
"whew, thought we're onto a perpetual motion machine winner for a second"
Perth, Western Australia.


class="style11">>and more light output per watt, than 220-240v lamps (because light >output is a function of current),

No, no, no!

[reviewing rules-of-physics-101]
Clive Woodward,

It is true, though, that a small filament bulb is much more focusable than a larger filament (required at greater voltages). This is why the Dedo light is much spottier as they can focus a small filament more effectively. Could this be why the perceived output of 110v fixtures seems in some people's eyes to be more than the equivalent 240v fixture?

Nick Paton
Director of Photography
High Def./Standard Def./Film
Aaton Xtr Prod owner operator
Brisbane, Australia
www.npdop.com


class="style11">>It is true, though, that a small filament bulb is much more focusable >than a larger filament (required at greater voltages).

Agreed. As per an earlier post of mine in this same thread, where I explained why 110v FAY bulbs [Par 36] don't have a 240v equivalent.

class="style11">>This is why the Dedo light is much spottier as they can focus a small >filament more effectively.

To remain scientific we have to be sure about an apple-to-apples comparison. Most 'lensed' lights used in film and TV are Fresnel’s. Dedo lights are one of the few exceptions, being PC [Plano Convex] - 'real' lenses. As such their LENSES do a better job of gathering as much light as possible and poking it where we want it, with minimum spill. As such they are more efficient in this regard than Fresnel lensed lights.

I've worked with stage lighting gear where 500w PCs [Strand 23] are far brighter than 500w Fresnel’s [Strand 123]. Exactly the same bulb [T1 / T17 / T24 etc]. Similar internal reflectors. Fresnel’s by their design scatter some light - to be caught [and converted to heat] by black-faced barn doors.

Clive Woodward,
reconsidering the future for perpetual motion machines
Perth, Western Australia.


Clive Woodward wrote:

class="style11">>and more light output per watt, than 220-240v lamps (because light >output is a function of current),

class="style11">> No, no, no! [reviewing rules-of-physics-101]

Yes, Yes, Yes. All gaffers should be physicists. Don't accept any hypothesis without testing

class="style11">>Light output is a function of POWER. Power is voltage times current. A >110 volt, 1Kw bulb outputs the same amount of light as a 240 volt 1Kw >bulb.

Agreed they all draw they same amount of power. However, the amount of light that comes out of the instrument is not always the same.

To wit :

A former partner of mine had the idea of using 220V. bulbs in our large lights (2K CYX vs. CVY, 5K DPY vs.LWB4, and 10K DTY vs. CP83 in M-R Fresnel’s) in order to reduce the size of the cable required. After a while, a couple of people (anal electric types) mentioned to us that the 220V 10Ks seemed to be putting out a little less light than the 110V units. (The difference in the smaller units was less.) We took Clive's theoretical position as our official position namely that all lamps of the same wattage, put out the same amount of light. We also said that any observed differences were probably due to their not having full 220V, or the lamps weren't seated correctly, or the lights weren't focused properly, or the reflector was off and every other thing we could think of.

When we tested the same fixture with a DTY and a CP83 under controlled circumstances (voltmeter, ammeter, fc meter) in the studio, it turned out that the 110V version did put out more light, also it had a slightly smaller spot and a slightly larger flood -- some 10 -15 years later, we're still arguing about the size of the flood, but regarding the amount of light, the DTY definitely did put out more. At this point, I can't recall exactly how much, but I seem to remember it was about 1/3 of a stop with a Mole 416.

class="style11">>Why do lighting people refer to their lights by wattage rather than >current?

Maybe it's because that's how they sell the bulbs ;o) Have you ever gone to a Supermarket and asked for a .8 amp bulb ;o)

Brian Heller
IA 600 DP


class="style11">> This is why the Dedo light is much spottier as they can focus a small >filament more effectively. Could this be why the perceived output of >110v fixtures seems in some people's eyes to be more than the >equivalent 240v fixture?

This is one of the reasons a Dedo light can spot so much...

The trick here is in the "all other things being equal" clause of comparisons :

As a for instance, some of the lamps that take 1k globes in the us at 110v actually use 800w. globes at 220v, because the real estate available in the envelope of the globe doesn’t leave room to make a 1000w. globe at 220 - there are a lot of factors...

The filament needs to have a higher resistance at 220 than at 110 so it either has to be longer or thinner or both or some combination of the two...but when made longer or thinner it needs more support so it doesn't fail from physical shock or fail to early when some of it oxidises...so there are constraints on the manufacture of different globes for different voltages.

In general (all other things being equal) the lower voltage filaments can be shorter and thicker than higher voltage filaments putting out the same amount of light, so in the case of PAR globes, more of the light can be closer to the focus of the parabola.

In the case of ellipsoidal reflectors (lekos) more of the output can be right at one focus of the ellipse...in the case of Plano Convex spots (of which the Dedo is a much evolved descendent) the lower wattage can more effectively create a point source, so the unit can focus down to a narrower cleaner spot than if the filament were big like an inkier (mini-mole)

This, by the way, is why we used ACL's (aircraft landing lights) in Rock ‘n’ Roll back in the day - those28v. filaments were ALL in the focus of the PAR 64 8" reflector, so the beams of light were very narrow.

Mark "all other things being equal" Weingartner


class="style11">>Light output is a function of POWER. Power is voltage times current. A >110 volt, 1Kw bulb outputs the same amount of light as a 240 volt 1Kw >bulb.

Now you see, I deliberately kept my mouth shut because I didn't want to be pedantic. But oh, no. Someone just had to get their oar in.

Clive Mitchell
http://www.bigclive.com


Clive Mitchell

class="style11">>Now you see, I deliberately kept my mouth shut because I didn't want to >be pedantic. But oh, no. Someone just had to get their oar in.

No one has mentioned heat loss. Does greater resistance in the filament of 220v filaments result in more power being converted to heat? Would the difference in physical size of the filament mean it has a difference surface area and therefore vents heat better?

Nick Paton
Director of Photography
High Def./Standard Def./Film
Aaton Xtr Prod owner operator
Brisbane, Australia
www.npdop.com


Take a 60 watt bulb and a 100 watt bulb and connect them in a series circuit. Which bulb will experience the greatest current flow? And which bulb will experience the greatest voltage drop?

Now take a 60 watt and a 100 watt bulb and connect them in parallel circuit. Which bulb will experience the greatest current flow? So which bulb will experience the greatest voltage drop?

Disclaimer : My opinions, thoughts, and beliefs are my own and may not reflect yours. The use of the pronouns "you, "some", and "many" to name a few are generalizations and without a proper name attached to them are not references to anyone reading my posts.

Walter Graff
Director
BlueSky Media, Inc.
www.bluesky-web.com


Nick Paton writes:

class="style11">>No one has mentioned heat loss. Does greater resistance in the >filament of 220v filaments result in more power being converted to >heat?

The way I learned it, light output is more a function of current (which is, after all, what heats up the filament), but not in a linear fashion. Vis-a-vis 120V lamps, 220v lamps are only somewhat less efficient, and 12v lamps a good deal more efficient, but certainly not by a factor of 10!

Like a lot of things I've learned, this could be all wrong -- but there you have it.

I use 50W PARs in my featherweight interview lighting kit, and the 220V versions of the essentially identical lamps (same nominal beam pattern) are appreciably less bright. Half a stop or so, I think.

Haven't measured it with an exposure meter, but when doing essentially identical (video) setups and shooting wide open I've had to position the lights about 1/4 to 1/3 closer to the subject to avoid adding gain.

It's the same story with my Rifa light, where filament size and positioning is about as non-critical as it gets. I only have one Rifa, so can't do a series arrangement, but for the other lights I generally prefer to run them in 120V series pairs when working in 220V countries.

Dan Drasin
Producer/DP
Marin County, CA


Hi Clive

To remain true to your scientific apple-to-apples comparison, a Strand Patt 23 is a profile spot (ellipsoidal in the US, dcoupe in France), which are literally mini projectors, a fixed reflector and lens, a gate with shutters and a pc focusable lens. A Strand Patt123 is a Fresnel, where the lamp and the reflector move together to focus the beam, you can't really compare it, therefore. A true comparison would be between a Fresnel and a PC spot. A PC being exactly the same construction as a Fresnel, but in place of the Fresnel lens, there is a PC (Plano Convex) lens. Also, with these old units its sometimes worth opening them up and removing 5 decades worth of dust!

On the other hand, I think its worth pointing out that the later model Dedo lights achieve their unique beam quality not only because of the small bulb, but also because of their unique optical design. They have a second travelling condensor lens that stays behind half way through the focussing range to gather any light bouncing around inside the unit and focus it on the front lens. This is why the unit doesn't lose light output the more you spread the beam, as is usual in other Fresnel type housings.

All the best

Roger Simonsz
DP/Operator
Vaguely focused in Paris
www.rogersimonsz.com


 


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