Lighting for beginners

[Garland Greene]

Hello I am a total noob to cinematography but I wanted to ask what 4k fresnels, 2.5 Pars for beams, and bay lights are? These are terms I have yet to come in contact with. Usually I film with natural light or practicals.

[Alan Rencher]

I don't think I've run across 4k fresnels (5k or more common). that just means that it pulls 4,000 watts of power, and a fresnel is a type of lens (fresnels are also used in lighthouses). A par can is a light without a lens (you may have seen these lighting many stages at concerts). Again, the 2.5 is just referring to the power consumption, 2,500 watts. As for bay lights, that is most likely referring to house lights in large studios. Those are the same lights that most warehouses use for over-head lighting.

[Garland Greene]

Wow thanks a lot man quick response. I googled all those lights and I felt like an idiot because I didn't understand. But that's what you have to do to learn I suppose is ask people. I'm trying to replicate the gritty look of Bad Lieutenant for my own film and those lights are what the DP used. Said he Bounced 4k fresnels and Used 2.5 Pars for beams in the church scenes and bay lights for the interiors. I dont understand what beams are. also, Is there a way I could build my own bay lights? With overhead lighting I'd be able to grab all the cuts I want because I like to do a lot of setups and shoot from different angles.

[Alan Rencher]

If the bay lights are being used as practicals (which means lighting that is also part of the set), You might be able to get some 300W incandescent bulbs and build something nice.

[Garland Greene]

That's exactly what I thought about doing. Give it a sort of Get Carter, Bad Lieutenant feel. I know Robert Rodriguez used 250w photo floods on el mariachi but I think I need to go a little stronger. Look natural enough. I'm making a gritty crime film with shootouts and crummy environments I don't need to be super fancy but in some scenes I would like to play around and experiment.

[Matthew W. Phillips]

Garland, a lot of it has to do with the size of the area you need lit as well as the speed of your stock. Using higher ISO valued stock (or camera settings, if digital) helps boost your light sensitivity but can cause grain (or noise) if boosted too much. Another consideration is the particular shot you want. El Marachi worked because RR got tight in on the camera and therefore was able to put those 250W lamps close to his actors.

 

As has been said many times before on here, when you are working ultra low-budget, money dictates style and not the other way around.

[Guest Christopher Sheneman]

Remember, daylight is free and the best. Check out Days of Heaven (1978). Shot almost entirely in the late afternoon "magic hour" with maybe 1-3 scenes (can't recall) using artificial light. The film is gorgeous, looks like a vision stock. It's on instant play Netflix if you want to check it out. That is the best example of shooting a film without using lights (or very few).

[Toby Orzano]

Read Set Lighting Technician's Handbook by Harry Box and then come back for any further clarification needed. I don't mean to be curt but there is already misinformation in this thread and it wouldn't make sense to rewrite here what's already been written eloquently in the book to get you up to speed. And another tip would be to get a patient gaffer who knows this stuff on your project and then you don't have to worry about it, or he can teach you as you go along. If you don't know what a 4k fresnel is then there is a LOT more that you need to learn before you can successfully and safely operate one. Again I'm not trying to be harsh, and I admire your ambition, but we have to be realistic about how much you can gain from this forum.

Edited December 30, 2012 by Toby Orzano

[Matthew W. Phillips]

I don't mean to be curt but there is already misinformation in this thread and it wouldn't make sense to rewrite here what's already been written eloquently in the book to get you up to speed.

 

Please share what misinformation this is so we may all learn from your knowledge?

[Toby Orzano]

I don't think I've run across 4k fresnels (5k or more common). that just means that it pulls 4,000 watts of power

 

It is correct that the number refers to the wattage, but it doesn't just refer to the wattage. You can tell what type of light it is because the different types come in standard denominations. 5k's are tungsten. 4k's are HMI. Tungsten ratings are 150w, 300w, 650w, 1kw, 2kw, 5kw, 10kw, 20kw. HMI comes in 575w, 1200w, 2500w, 4kw, 6kw, 12kw, 18kw. (ARRI recently added a 1.8kw and I think I heard 9kw too.) Also some portable units at 200w, 400w, 800w.

 

A par can is a light without a lens (you may have seen these lighting many stages at concerts).

 

This is kind of right. A PAR can fixture itself does not have a lens, but the bulb assembly has a lens and reflector built in, and are available in different spreads (wide, medium, narrow spot, very narrow spot).

 

However, the original post refers to a 2.5 PAR, not a PAR can. PAR cans are a type of PAR but not all PAR are PAR cans. A 2.5 PAR is a 2.5kw HMI PAR. HMI PARs of all sizes have lenses that either drop in or pop in to the front of the fixture to focus the light, also available in different beams (spot, medium, wide, super wide [also called stipple or bugeye, and some are frosted], and sometimes fresnel). There are open face tungsten PAR unit that have no lens at all. Ultimately what makes a PAR a PAR is the reflector, as PAR is an acronym for Parabolic Aluminized Reflector.

Edited January 10, 2013 by Toby Orzano

[Zachary J Esters]

The more you know!

 

 

Zachary J. Esters

[Guy Holt]


Please share what misinformation this is so we may all learn from your knowledge?


 

Alan’s following statement is also technically inaccurate:

 


4k … just means that it pulls 4,000 watts of power …. the 2.5 is just referring to the power consumption, 2,500 watts….


 

Technically speaking the 4k and 2.5k designation of the HMIs above is not their power consumption, but their light output. Unlike incandescent lights, HMIs consume more power than they generate in light. The relationship between what they generate (their True Power) to what they consume (their Apparent Power) is their Power Factor.

 

Here is a simple explanation of Power Factor in HMI & Kino ballasts. With a purely resistive AC load (Incandescent Lamps, Heaters, etc.) voltage and current waveforms are in step (or in phase), changing polarity at the same instant in each cycle (a high power factor or unity.) With “non-linear loads” (magnetic and electronic HMI ballasts) energy storage in the loads, increases the amount of current drawn and results in a time difference between the current and voltage waveforms – they are out of phase (a low power factor.) In other words, during each cycle of the AC voltage, extra energy, in addition to any energy consumed in the load, is temporarily stored in the load in electric or magnetic fields, and then returned to the power distribution a fraction of a second later in the cycle. The "ebb and flow" of this nonproductive power increases the current in the line. Thus, a load with a low Power Factor will use higher currents to transfer a given quantity of real power than a load with a high Power Factor. In short, HMIs draw more current to generate the same wattage of light as an incandescent fixture.

 

The poor Power Factor of HMIs, Kinos, CLF lamp banks, and even LEDs, have been vexing set electricians for years. For more information about the adverse effects these loads can have on generators and power distribution systems, and how to remedy them so that you can operate bigger, or more small, lights on portable generators or house power than has ever been possible before, join me in a workshop I am teaching on Feb. 16^th titled “Lighten Up: Doing More with Less without Compromise.”

 

 

As part of the same workshop series, New England Studios, Talamas Broadcast, and Production Hubwill be sponsoring a workshop on “Video Lighting Design” by L.D. Richard Cadena on Feb. 9th. Noted Focal Press Author, ETCP Trainer, and Founder of the Academy of Production Technology, Richard’s workshops are both lively and informative. Log onto bit.ly/nptwkshps for more workshop information and registration details.

 

Guy Holt, Gaffer, New England Studios, Lighting & Grip Rental in Massachusetts