300w enough for outdoor shot?
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Moseph
Veteran
If you're using it as a top light, whatever light you gain from the source itself, you'll easily lose by it acting as a barrier between the sky and the talent. Not to mention that CTB gel will knock down the light by around 1.5 stops, so you'd really have the equivalent of closer to 100w.
If you want to knock down the background, I would probably set up a net with some duvatine stretched over thee top to act as a shade over the net itself.
If you want to knock down the background, I would probably set up a net with some duvatine stretched over thee top to act as a shade over the net itself.
Jimmy Moss
Well-known member
This is what reflectors are for.
Jordan Scott Price
Veteran
Paul Hudson
Vacuum Tube Member
1200 watt HMI is the bare minimum. I prefer a 2500 HMI for this. And of course, a reflector board is far brighter than either of these but on an overcast day you are going to have very little to bounce.
Thanks for the replies, saved me a bunch of money/time.
I've already considered flagging the sun light around the subject but that seems like a tedious task considering how large of a sheet i'd need. Is there an efficient way of doing this?
A reflector board sounds good but I feel like it wont create that top light look similar to the reference photo.
Would a 1.2 hmi do the trick?
I've already considered flagging the sun light around the subject but that seems like a tedious task considering how large of a sheet i'd need. Is there an efficient way of doing this?
A reflector board sounds good but I feel like it wont create that top light look similar to the reference photo.
Would a 1.2 hmi do the trick?
It is the smallest instrument which might. Whether or not it will is another question.
j1clark@ucsd.edu
Veteran
I'm planning to shoot outside on an overcast day in the forest/woods. So that's a lot of light cut out from the sun.
I want to punch the subject out of the background by making them brighter than the background.
So I was thinking of adding a ~300w china ball as a toplight. I could even do 2 china balls and mask the top and sides with a black blanket.
I'm just wondering whether this 300w will do anything before I go out and test it.
I'll be running power off a car battery being charged by a running car. What's the max amount of watts I can pull from a car battery in case I need more light?
Ref shot:
Others have given some ideas.... one that just occurred to me is to use a portable green screen. If the point of your lighting is to really separate the actor in the foreground from the back ground. Here's the idea.
Take a 'plate' of the background. Then with the person in front of the green screen with the camera setup at the location, and expose for 'good lighting' on them.
When you key out the green screen you will have the 'plate' in the background and can adjust the levels to make the contrast much more than what you would ordinarily have.
I wasn't able to find an example. But I've seen this on some behind the scene segments, where there's going to be quite a bit of CGI for the shot, but by using the portable greenscreen, you can get the 'identical real' lighting, then add to the 'set' via CGI...
I'd think the same principle would work for creating higher contrast between subject and background in your case.
mattsdni
Active member
http://calc.arri.de/calculator
pick a light, find your exposure. Don't forget about diffusion. That will cut a stop or so.
Looks like you could probably get by with a 1.2K if you shoot at iso 800.
pick a light, find your exposure. Don't forget about diffusion. That will cut a stop or so.
Looks like you could probably get by with a 1.2K if you shoot at iso 800.
David W. Jones
Veteran
5K through a silk from a bucket truck.
starcentral
Veteran
Just to offer some objection, I'm not sure I will agree with what the others have said about needing HMI's to pull this off.
If you get in a forest on an overcast day, you are maybe going to get f8-f11 @ 800 ISO 1/48 24fps. I don't know how many hours you need to shoot, but if you shoot early in the mornings and in late afternoons you can definitely establish a working range of f5.6 to f11 with your ambient light. The time window would be limited for sure, but if you break your shoot into several days and plan your shots really well perhaps you can get what you need.
Since its overcast, you do not need overhead silk or diffusion. I would mostly only suggest you use that in direct sun or a cloudy day so you get continuity between your takes.
Having said that, for medium and close up shots an ARRI 1k tungsten will put out 105 foot candles at 20 feet using a medium focus beam. I happen to know for example that my camera needs 42 fc to expose middle gray at f4. That means if I color correct the ARRI 1k and even lose a stop, I'm still getting 52.5 footcandles on my subject, or like I said around f4. That's 20 feet from my subject and on a medium focus setting. If you make it more spot or move the light closer you're easily going to be able to get 1 stop over your ambient and get a nice fill effect. Go for a flat image on location, and more fill can be done on the skin in post if needed. It is really easy to do in your editing software alone incase you don't have fancy post production tools like After Effects.
If you are forced to shoot in the sun, then only shoot your close ups and medium shots at that time and use large overhead diffusion fabric you can buy or make and tie between trees in a open area. Then save shooting your wides for that overcast day. You might have some continuity issues but again, storyboard it, plan your shots, and if its quick no one will notice.
Resources:
- For footcandle performance on ARRI products check out this link
- To see a 1200w HMI's in action both outdoor in direct sunlight, as well as indoors take a look at this YouTube video.
- To read more about how I determined what FC I needed for my camera, read here.
P.S. That Arri lighting calculator is also pretty useful, great find! By the way if you actually use it you will easily see that a 1.2kw at 40 feet on spot mode requires f64 at 800ISO. That is waaaaaaaaaaaaaaaayyy too bright for a interior forest shot.
If you get in a forest on an overcast day, you are maybe going to get f8-f11 @ 800 ISO 1/48 24fps. I don't know how many hours you need to shoot, but if you shoot early in the mornings and in late afternoons you can definitely establish a working range of f5.6 to f11 with your ambient light. The time window would be limited for sure, but if you break your shoot into several days and plan your shots really well perhaps you can get what you need.
Since its overcast, you do not need overhead silk or diffusion. I would mostly only suggest you use that in direct sun or a cloudy day so you get continuity between your takes.
Having said that, for medium and close up shots an ARRI 1k tungsten will put out 105 foot candles at 20 feet using a medium focus beam. I happen to know for example that my camera needs 42 fc to expose middle gray at f4. That means if I color correct the ARRI 1k and even lose a stop, I'm still getting 52.5 footcandles on my subject, or like I said around f4. That's 20 feet from my subject and on a medium focus setting. If you make it more spot or move the light closer you're easily going to be able to get 1 stop over your ambient and get a nice fill effect. Go for a flat image on location, and more fill can be done on the skin in post if needed. It is really easy to do in your editing software alone incase you don't have fancy post production tools like After Effects.
If you are forced to shoot in the sun, then only shoot your close ups and medium shots at that time and use large overhead diffusion fabric you can buy or make and tie between trees in a open area. Then save shooting your wides for that overcast day. You might have some continuity issues but again, storyboard it, plan your shots, and if its quick no one will notice.
Resources:
- For footcandle performance on ARRI products check out this link
- To see a 1200w HMI's in action both outdoor in direct sunlight, as well as indoors take a look at this YouTube video.
- To read more about how I determined what FC I needed for my camera, read here.
P.S. That Arri lighting calculator is also pretty useful, great find! By the way if you actually use it you will easily see that a 1.2kw at 40 feet on spot mode requires f64 at 800ISO. That is waaaaaaaaaaaaaaaayyy too bright for a interior forest shot.
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Hm, I don't know about this, your calculation seems off. There's just no way that a 1k 20ft away is going to do anything even on overcast day, especially if it's gelled. There was one shoot I was on where all we had was an ungelled 2k 5 ft from the actor on a close up and it did practically nothing.
starcentral
Veteran
Many things are hard to believe, but footcandles don't lie.
What light and camera were you shooting with? Again, the FC you need for your camera to get a certain aperture will depend completely on the camera and working ISO of it. My example was based on an effective ISO of 800. My guess is you were shooting with a stock camera like maybe HVX which was 320ASA if I remember correctly? Add a 35mm adapter and you were probably down to a working ASA of 80-160? I know, because I use to shoot with 35mm adapters too, but now using the Sony F3 which is 800 ISO. It is like friggin night vision.
What light and camera were you shooting with? Again, the FC you need for your camera to get a certain aperture will depend completely on the camera and working ISO of it. My example was based on an effective ISO of 800. My guess is you were shooting with a stock camera like maybe HVX which was 320ASA if I remember correctly? Add a 35mm adapter and you were probably down to a working ASA of 80-160? I know, because I use to shoot with 35mm adapters too, but now using the Sony F3 which is 800 ISO. It is like friggin night vision.
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Wave of Light
Carbonite Member
The 1200 par w/ electric ballast is a good choice. It uses less power than a 5k and you will not have to add CTB. I know its common, but I cringe at the sight of tungsten lights on a daylight background or the other way around. In your example the color is consistent. Normally, I don't like to dim HMIs, because they go up 1000 or so Degrees Kelvin (blue), but since it's an over cast you may need/want this.
You will need diffusion, big soft light on an over cast day. Not knowing what you are shooting on, I'd say bring an assortment. I love Grid cloth, but it takes away a lot of light. It does come in Full, 1/2, and 1/4. A 4'x4' at the minimum as close to your hero as you can get it, but out of the shot. Not on the doors. If you have to, hang a roll. You won't be cutting it then.
After the diffusion and dimming if you still need to take some away (which I doubt) throw in some steel.
Rent a genni, Honda i2000 will do it. You may want to keep your inverter standing by, for camera, monitor, or what ever. You could use the remaining power on the genni.
Always get more than you think you need, and then reduce the extra, you can't get more if you don't have it.
Your shot will be beautiful.
You will need diffusion, big soft light on an over cast day. Not knowing what you are shooting on, I'd say bring an assortment. I love Grid cloth, but it takes away a lot of light. It does come in Full, 1/2, and 1/4. A 4'x4' at the minimum as close to your hero as you can get it, but out of the shot. Not on the doors. If you have to, hang a roll. You won't be cutting it then.
After the diffusion and dimming if you still need to take some away (which I doubt) throw in some steel.
Rent a genni, Honda i2000 will do it. You may want to keep your inverter standing by, for camera, monitor, or what ever. You could use the remaining power on the genni.
Always get more than you think you need, and then reduce the extra, you can't get more if you don't have it.
Your shot will be beautiful.
What was the scenario like? Was it a sunny day out in the open with no shade?
mattsdni
Active member
That could work if you bring some soft fill sources. Just make sure the subject is lit well and not in shadow
Just going by the arri calc online, they show about 90 fc at medium spot from 20 feet.
Good number on fc for exposure. I generally find myself targeting 50 fc for iso 400 @ f/4. Don't forget that CTB will knock down your 1K by 2 stops. That brings you down to about 25 fc.
Well, not really. If you use hard light on location you will not be able to soften it in post. You can only reduce contrast. You would still have hard shadows. I would suggest some medium diffusion. 1/2? maybe. That will cut about 1/2 a stop again so now you're down to about 16 fc. A heavy overcast forest will be around 800 fc. Hence the HMI.
Let's say we go with ISO 100 to match the overcast. That puts the forest at f/8. With the 1/2 diffusion a 1800W HMI par would give you a f/5.6, just for a little boost. If you had to you could get by with a 1.2K. I would probably go with a 2.5K to be safe. You can always throw a scrim on it.
Michael Carter
Veteran
That sounds like a nightmare waiting to happen. You really need a nice, full raster camera and a lot of experience doing greenscreen and a full day of test shooting and a day of test comping to even come close to a decent shot like this (and if you've seen this in BTS, they're using tons of light and huge generators and really sharp 4k film scans with every hair beautifully outlined - and they're not doing it because there's no light, they're doing it to add effects or backgrounds or elements. And they're using advanced matchmoving software and computerized camera movements and a dedicated effects company with a tech director flown in and on set, and... and... and...)
If all you can afford is a 300 watt light, don't even go this route. Seriously. Bring in some big shiny reflectors and do your best.
Just my .02.
+1. We talk funny in the lighting biz
Except that I wasn't shooting at night, and neither is the OP. The question is would a 1k do anything in an overcast outdoor situation during the day. That particular shoot was done shortly after it stopped raining and so the condition was completely overcast; the light was practically right up on the actor's face and it was like it wasn't even there. That's why I have real trouble believing that a 1k gelled light would do anything in an outdoor situation.