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Does this HMI exist?


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#1 Ville Pakarinen

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Posted 01 September 2014 - 11:12 AM

I'm trying to zero in on an HMI that would be useful as a general fill in rather cramped interiors and powerful enough to fill in the sun - OR work as the sun - in one exterior scene. The exterior scene will be just two people sitting on a bench, so it doesn't require a huge lens to cover an area the size of a soccer field. How possible is this for one HMI? Is 1.2K too small as sunlight or filling in the sun? How about 1.8K?

Also, I'm not quite sure I understand how PAR differs from open face and fresnel. What I've read is that PARs can be focused very well into hot spots. But how does this differ from fresnel? Is PAR still less controllable than fresnel with the benefit of more bang for the buck? Also, what's the difference between PAR and open face when punched through diffusion?

Danke! Thanks!


Edited by Ville Pakarinen, 01 September 2014 - 11:15 AM.

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#2 Guy Holt

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Posted 01 September 2014 - 01:57 PM



I'm trying to zero in on an HMI that would n the sun - OR work as the sun - in one exterior scene. The exterior scene will be just two people sitting on a bench, so it doesn't require a huge lens to cover an area the size of a soccer field. How possible is this for one HMI? Is 1.2K too small as sunlight or filling in the sun? How about 1.8K?

 

 

If you plan your shots properly, you don’t need as big of HMIs as you may think when shooting the elaborate cross cutting required by dramatic scenes.  With proper planning you can get away with nothing more than a 12x Silk, 4kw Par, and 1.2kw Par – all of which you can run on a modified Honda EU6500is with a Transformer/Distro that provides a single 60Amps/120V circuit.

 

The approach that I find works best is to wait to shoot the establishing master shot until the sun is in a backlight position. Up to that point I shoot the close coverage under the full silk. Shooting the close coverage under a silk offers a number of advantages. The silk takes the directionality out of the sun and knocks down its’ level by two and half stops so now you can use smaller HMIs to create consistent modeling in all the close-ups. Shooting into talents' down side under a silk, I find that a 4k Par through a diffusion frame is a sufficient key source for a good size two shot. You need the diffusion because a bare par will be too harsh in close up. When shooting close coverage under the silk, nets behind your talent will control the background from blowing out.

 

The advantages to waiting to shoot the wide master until the sun has moved around to a back light position are many. One, your background is also back-lit so the discrepancy in exposure between the background and your talent to camera is not that great and so you can open up to gain exposure of your talent in the foreground without burning out the background. Two, when your background is back-lit, it does not over expose because of the discrepancy in levels under the silk and outside the silk – it helps to strike a good balance.   Three, your background looks better because it is not flatly lit, but has some contrast. And four, with the sun in a backlight position, the shadows of the silk frame and stands are thrown forward, which enables you to frame wider before picking up the shadow of the hardware.

 

Finally, since the silk takes the directionality out of the sun and knocks down its’ level by two and half stops a 4k HMIs par without diffusion has enough output to create the look and feel of natural sunlight. For more detailed information on powering 4k HMIs on portable gas generators, I would suggest you read an article I wrote on the use of portable gas generators in motion picture production.

 

Guy Holt, Gaffer, SceenLight & Grip, Lighting Rental & Sales in Boston.


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#3 Ville Pakarinen

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Posted 01 September 2014 - 02:03 PM

Wow! Thanks for a very detailed description!


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#4 Ville Pakarinen

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Posted 01 September 2014 - 02:15 PM

Not sure we can afford a 4K, or even two HMIs. Although one guy said he could rent two 1.2Ks very cheaply. But the brand sounded obscure: Cinemobil 1.2k HMI open face. Anyone know these lights?

We would like to power the HMI using only nearby wall sockets. How much can you do outdoors with one or two relatively inefficent HMIs?


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#5 David Mullen ASC

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Posted 01 September 2014 - 03:41 PM

You get the brightest HMI you can, which in your case I guess would be a 1.8K, and you'll learn if it is bright enough. What else can you do???

 

Truth is, outside in daylight, it's only going to be bright enough in a head-to-toe shot to look like hard sunshine either on a heavily overcast day, deep shade, or at twilight -- otherwise only with a narrow lens when shooting tighter, like a waist-up shot at best in normal overcast.  And of course it won't compete with real sunlight, but in that scenario, a shiny board would be better.  For fill light, it's fine, even something smaller would work depending on the area you want to fill or if you want to soften it.


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#6 Ville Pakarinen

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Posted 05 September 2014 - 09:01 AM

I think I found a perfect location for this kind of low budget outdoor shooting. Basically, it's just a minute-long scene of two people sitting on a bench talking. It's supposed to look like it's spring, so I think we'll go for golden hour look.

The street is almost perfectly aligned in the east-west direction. There's a university on the south side, providing shade for the close ups. I think it's summer in that satellite image, so the shadow of the building isn't covering the entire bench or the trees. But we'll be shooting at the end of this month, so the sun will be much lower here in Finland. Now, my plan is to shoot the close ups during the day when the sun is hiding behind the university building. I'll use the biggest and badest HMIs we can afford to model the golden hour sun shining from the west. Then, when the sun reveals itself in the west, we'll shoot the master as wide as possible with the HMIs we can afford.

The great thing about this location is that the trees behind the bench form a sort of niche where the sun can't shine, so it will look pretty much the same in the noon and during sunset. Also, it's a very quiet street on the weekends because no one lives there. AND, some of the students were celebrating the start of semester on the bench, and I asked if it was possible for us to use the schools electricity. She said the school is very cooperative :D

What do you think?

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#7 Albion Hockney

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Posted 06 September 2014 - 02:35 PM

I think with a 1.8K hmi through like a 4x4 of 251 or 250 and maybe 1/4 or 1/2 CTO you could get away with shooting mediums and close ups with a golden hour look in that situation..... but anything wider I think it will be a hard sell. the light will have to be pretty close to talent to get enough punch.

 

 

I'd recomend toning back the look and not blasting the HMI.... Diff it up heavily and you can create a really nice more ambient soft look kinda like whats in your picture there but you can model it up a little and give it a little more directonlity ....then you can cut to your wide without any lights natrual.

 

 

I think when your first start using HMI's the notion is often to blast light cause its fun to play with the new toys but often its a good decsion to be subtler about it.

 

 

In general I wouldn't use an HMI for a day exterior if it was under 4K its just not so worth it unless its a special circumstance or something like one close up. I'd use overheads and bounce materials


Edited by Albion Hockney, 06 September 2014 - 02:38 PM.

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#8 Matthew Rogers

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Posted 06 September 2014 - 08:08 PM

The problem is not getting the people to look good, especially if you are going for "Golden Hour" but to have enough light to get the background to match what you've got on the people. Honestly, a 1.8k is great on a cloudy day for some stuff, but outside with the sun it's worthless unless you are fairly close and don't you diffusion-which then normally looks bad.


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#9 Ville Pakarinen

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Posted 07 September 2014 - 07:32 AM

The problem is not getting the people to look good, especially if you are going for "Golden Hour" but to have enough light to get the background to match what you've got on the people.

You mean enough light on the people or enough light on the background as well? The trees behind the bench are almost completely in shade, so the sun can't reach them in the wide shot.


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#10 Albion Hockney

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Posted 07 September 2014 - 01:39 PM

I think mr rogers is over simplifying a little....you dont need to diffuse light to look good ....especially if you keep the sun as like a rear third edge or something ....and you can use light diffusion still and get a decent stop.

 

The trees in shade will look fine as well....it will just look like buildings or w/e are creating a little spot of sunlight on the bench.

 

 

I think your big problem is a 1.8k will never be enough to light your wide shot for a golden hour direct sunlight effect.


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#11 Ville Pakarinen

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Posted 07 September 2014 - 03:46 PM

Yeah, very true. Did some research and found out 1.8K is some five stops dimmer than the sun - depending on distance and other factors of course.

But... The scene in question is actually only about 20 seconds long. So, I was thinking we may be able to shoot the coverage and master in a very short period of times - thus using the sun as the key in all shots. That would make things a lot more convenient.

So I was thinking of placing 12' x 12' reflector on the right side of the bench, then firing some additional fill with two open face 1.2Ks.

Now, when using a reflector to bounce back warm sunlight, doesn't it ruin the the golden hour effect where the opposite side should be lit by the cooler ambient light from the sky? So I was thinking of cooling down the opposite side with two 1.2Ks and half CTB.


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#12 Albion Hockney

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Posted 08 September 2014 - 12:53 PM

Generally the color temp of the bounce is not an issue.  If your concern is just natrualism no it won't be an issue bounced light comes from all kinda of places and in a urban setting honestly that bounce light on fill side of faces is more likley from the ground or other buldings then the ambient blue in the sky. That is actually an interesting point though I never thought about I haven't really seen anyone blue up there fill side before...I have heard of it for interiors ....reflecting ambient skylight that is super blue into spaces but never on a day exterior....might create an interesting color contrast.

 

 

I think in your circumsatance the idea to B up your 1.2ks isn't bad but I think likley the bounce back of the sun will be far more powerful and the 1.2ks wont really do anything at all and it will just look the same. and in your close ups with a 12x honestly your in danger of too much fill if anything (assuming you are trying to keep a nice natrual contrast) you will want to keep the 12x a decent distance away....whats nice about big rags is that you can keep them at a nice distance, get a super soft ambient fill and still get a nice punch.

 

 

I would recomened a 12x of bleached muslin for closeups and maybe a 12x of ultra bounce for your wide shot. In your close ups you might want to cut the sun with a 4x4 of Opal or 251 or something just to bring it back a little if its too peircing. 

 

 

I have never heard of any blueish cloth materials for bounces but maybe you could look into that if you were really interested in that. or for your close ups just get a 4x of 1/2 CTB and place it infront of there fill side between the bounce and the talent.


Edited by Albion Hockney, 08 September 2014 - 12:54 PM.

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#13 Rob McGreevy

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Posted 09 September 2014 - 03:34 PM

I think it's possible the M18 can do the job for you, I've encountered a few scenarios where using one outside during the day was helpful. It all depends on your set up and what the sun is doing, of course. I tend to think that controlling the existing light with diffusion or reflectors is the best option if you can, but if the light is going to either hide behind those trees or a building for most of the day then you may need to use a light - of course a bigger light would better if you were able, but if an M18 is all you can afford I've seen that work just fine for mediums and close ups. 

 

If if you can though I would shoot the wide first when you have the available light and establish that look, then for tighter shots try to match what it was doing with lights when the sun later goes behind trees/buildings or whatever...

 

The Rag Place does make muslins in a few different shades of blue, as well as blue grid cloth diffusion. They're not that common and may not be readily available as rentals items as far our as Finland but you never know till you ask... fabric stores also sell muslin by the yard, I've never seen blue personally as I think that's a specialty film item, but you never know.

 

My other thought though is if you can afford an M18 and two 1.2ks, can you not instead just get one 4k? if power's a concern then that's understable but in my experience when you're trying to imitate the sun one large source typically yields better results than several smaller ones...I've gotten away with just an M18 when logistics required it, but if I'd had my druthers I'd rather it have been an M40 or larger, had the option of moving it closer or further away to get the effect I wanted while still maintaining the punch, and then bounced back the light from that on the fill side as needed. 


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#14 Ville Pakarinen

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Posted 10 September 2014 - 11:21 AM

I think we could get a 4K or 6K. How wide an area can a 6K cover in shade?

Also, how useful are HMIs in creating a golden hour look when you have to use CTO? Wouldn't some big tungsten fresnel be better taking into account the cost and light loss of an HMI?


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#15 David Mullen ASC

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Posted 10 September 2014 - 12:44 PM

If you are committed to this orange late afternoon sun look then tungsten is a good choice, it's a lovely color, but you have to use a powerful punchy unit and have the generator power for it. A 6K HMI with Full CTO is still brighter than a 5K tungsten. But 9-lights and 12-lights with some narrow globes in the fixture make a nice sunset light, or make a 10K PAR. The multi-bank lights make shadows with multiple edges but it's not too distracting in wider shots, you see this effect in many movies shot by Storaro (see example from "Little Buddha" below). If it bothers you in a closer shot, a frame of very light diffusion will blend the globes into one semi-hard source.

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#16 Albion Hockney

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Posted 10 September 2014 - 12:59 PM

Maxi's are great units .....and keep in mind if you go through some diffusion it will pretty much unifiy the source. a 9 or 12 light can do late afternoon sun in a moderatly wide shot if everything else is in shade (like i'd say slightly wider then that bench....but not much). and for your close ups you could get away bouncing it.....it would a little more of a soft sunlight look though and will be very warm.

 

 

I think 1/2 CTO on a 6K Par through lite diffusion is also a nice option though. This will cover about as wide as a two shot of the bench just like the maxi would.

 

 

Keep in mind earlier you were saying you trying to power from a building....any light over 2k you will need a generator. a 4k hmi par you can run off a small generator  but anything bigger then that you will be talking about a truck towed generator and will need an expereinced gaffer/best boy to run power for you. These are big lights that take several hands and much heavier duty equipment to work with.


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#17 Ville Pakarinen

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Posted 10 September 2014 - 01:20 PM

Keep in mind earlier you were saying you trying to power from a building....any light over 2k you will need a generator. a 4k hmi par you can run off a small generator  but anything bigger then that you will be talking about a truck towed generator and will need an expereinced gaffer/best boy to run power for you. These are big lights that take several hands and much heavier duty equipment to work with.

Yeah, change of plans. The producer talked about having our power needs met by an electric company. Quite expensive, but they could bring us a distro box on location. Do you think I'll survive with my rudimentary understanding of electricity when the power company is doing all the messy stuff? I can calculate loads and stick a plug into a socket :)


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#18 Albion Hockney

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Posted 10 September 2014 - 01:50 PM

well with only one large source you'll probably be fine with the distro box but you will need to know about the connections (bates, twist lock, etc). Also keep in mind a 6k HMI or 12 light maxi .....well especially the 12 light ....it probably weighs 100lbs + and you will need a big combo stand along with a few people to place the light and raise the stand. if you want the light to be high up that will be something to figure out in its own right.  I probbaly wouldn't go this direction unless you have a crew that has had some expereince ....if its a short shoot like you say and your starting out maybe even ask the rental company about having someone come out or ask a favor of a more experienced gaffer.

 

 

not sure your level of experience here not to condescend and such but just wanted to give fair warning


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#19 Rob McGreevy

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Posted 10 September 2014 - 01:52 PM

A 6k with a wide lens it will cover a very wide area - keeping in mind that the wider the lens the more punch you lose, plus the output lost from the glass itself...but with a 6k you'd still be getting quite a bit even with the super-flood lens in.

If you went with an M-40 that's a lensless fixture, so you get to keep all your output, you don't lose any to the glass itself. An M-40 is also easier to lug around - lighter, few parts, and it can easily go on a combo stand. A 6k can theoretically go on a combo stand as well, but safely raising it can easily turn into a 2-3 person job, so depending on your man-power situation you may want a roadrunner for that.

 

I'm going to echo David's post about tungsten, it could work but you need much bigger units to use outside during the day, tungsten is not at all effective in day light and as it's generally considered in inefficient solution HMIs with color correction is still more common - you can color correct big HMIs all day, you don't lose that much, you just have to make sure your gel doesn't absorb too much of the blue light and melt - best to skin it over a frame to avoid that. CTO would work, CTS is also a good option - a lot of DPs and gaffers I've worked for prefer it because it's  less red and a little more "golden" than CTO, just another option to keep in mind. You can get creative too, on the show I just wrapped the gaffer and DP really like Bastard Amber for golden hour because it has a subtle pinkish tint to it that looked very of sunset-y. That may work better here in Texas where the sky can get quite colorful at sunset, figure out what color sky you like best and choose your gel accordingly.

 

As for power Albion, needing a genny for anything bigger than a 2k is not necessarily true - keep in mind he's in Finland, they're on a 230V, 50hz power system with I believe C/F style power outlets, his electrical distribution concerns are likely quite different from ours. I'm somewhat familiar with how Europe's power system generally works, but not at all acquainted with the day to day specifics. I've heard it is quite common to have the power company come drop a line to a box for you over there, that being the case taking the genny out of the equation simplifies things on the electrical end quite a bit, assuming of course the grid power is reliable. Apart from that just know what the output connectors are on the distro box, the input connectors on the HMI ballast, make sure you have any necessary adaptors and you should be good to go. And of course make sure you have the necessary man-power - if all you have is one M40 and the budget is tight, one person can operate that light if need be - not ideal, but highly possible. If you go with a 6k you need more guys, there's no way around that. If the power company is laying all your cable for you then that's taken care of, if not then you probably want several guys to manage the distro. And ideally you should have a separate grip crew to move any frames around if you plan on using any - the bigger the frame, the more grips.

 

That was much more than I intended to write, I hope you found it useful though.


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#20 Albion Hockney

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Posted 10 September 2014 - 02:02 PM

ah yes, europe! I forgot.

 

Yea echo everything Rob said about crew size and grip needs. Be careful .....big lights = more time and more people ....having a 12x frame and a 12 light maxi vs just having one m-40 or just a 12x for fill will really change the dynamics of the set.


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