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Questions from a shoot


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#1 Daniel Madsen

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Posted 14 April 2006 - 11:18 PM

I was the gaffer on this shoot that took place in a very small and old apartment- of course the way the place was wired reflected that. I found myself having to switch the breakers on and off for two reason, one because there was an unusual amount of outlets belonging to a single curcuit (so the breaker tripped a lot) and two because I needed to find out what outlets belonged to what breaker. So here's my question- does a breaker get more likely to trip the more it is used? They have to be replaced eventually ight?


That's technical this is asthetic- any advice on lighting for a person's reflection in a window?
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#2 Michael Nash

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Posted 15 April 2006 - 02:27 AM

If I understand it correctly, older style breakers work on the heat buildup from excess current, requiring a small "cooling off period" before they can be sucessfully reset. These are the same type of breakers that can sometimes allow overcurrent to occur for quite a while before tripping.

There are other types of breakers that can work much faster (such as GFCI's) and work by a different principle.
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#3 Michael Morlan

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Posted 15 April 2006 - 11:37 AM

Modern, magnetic breakers do not trip earlier as they age. They may eventually suffer a mechanical failure after many cycles and adverse conditions. Usually that is pretty instantaneous.

When trying to trace branch circuits to their breakers, consider using an audio tracing tool. There's a picture of one in my article on powering your set on DV.com. (Note: There are a couple factual errors that slipped by me and the editors but the information is generally accurate.)

http://www.dv.com/ne...view/morlan0505

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#4 Phil Rhodes

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Posted 15 April 2006 - 03:03 PM

Hi,

I hate to be the doombringer here, but it should be pointed out that if a breaker is repeatedly tripping, you are doing something wrong. Breaker will stop tripping once you stop doing wrong things!

Phil
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#5 Daniel Madsen

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Posted 15 April 2006 - 03:33 PM

Phil, I'm aware of that. I got a little frusterated during the shoot because the breaker box showed there to be six seperate curcuits, but I could find only two that were entirely or partly for wall outlets.

Mr. Morlan- I'll check out your article on dv.com

Thanks everyone.
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#6 Michael Nash

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Posted 15 April 2006 - 06:39 PM

That's technical this is asthetic- any advice on lighting for a person's reflection in a window?


The basic principle is that the subject's light has to be A LOT brighter than the view seen through the window. Glass is a pretty poor reflector. Almost all the light is transmitted rather than reflected, that's why you can see through it so well!

Nighttime views looking out are not much of a challenge, but trying to compete against a sunlit exterior requires some serious cheating. You can do a few things to help you along though. Plan on framing this reflection fairly tight, so that you can ND the glass easily if you have to. Position the reflection against a darker portion of the background. Often times it takes a hard light fairly close to the subject to get the exposure hot enough. And speaking of "hot," you're likely to cook your talent in the process...

You can often get away with a pretty hard key light for the reflection, since the reflection is kind of "mixed" or "ghosted" against the background anyway. Use this as an opportunity to do something dramatic; make the face completely side-lit (making half a face in the refelection), or use a hard toplight to make dark (invisible) eye sockets in the reflection. Get creative.

Using shallow depth of field and a little movement from the actor can also help distinguish the reflection from the background. And of course focus is measured by the distance from the film plane to the glass PLUS the distance from the glass to the face!

Judge exposure balance between foreground and background by eye. Don't bother trying to take spot readings of the reflection or compensate for the light loss of the glass, you'll just drive yourself nuts! Of course with video, WYSIWYG on the monitor.
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#7 Luke Prendergast

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Posted 15 April 2006 - 07:03 PM

Glass is a pretty poor reflector. Almost all the light is transmitted rather than reflected,


This varies with the angle of incidence. The less oblique the incident angle, the greater the reflection, so you can cheat this way as well. Clear glass acts almost as a mirror when viewed from a very acute angle.
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#8 Michael Nash

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Posted 16 April 2006 - 05:51 PM

This varies with the angle of incidence. The less oblique the incident angle, the greater the reflection, so you can cheat this way as well. Clear glass acts almost as a mirror when viewed from a very acute angle.


This is true. I didn't mention it because light coming through the glass is usally the biggest problem regardless of angle. But you're absolutely right about acute reflections, and you can use that to your advantage for ceratin shots.
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#9 Mario C. Jackson

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Posted 19 April 2006 - 10:25 AM

Whenever I am on a shoot I usally give my gaffer my circiut breaker finder , and the two of us find out what lines are on the same circuit. This will cut down on alot of problems during shooting time.
Hope this helps
Mario Concepcion Jackson

Edited by Mario C. Jackson, 19 April 2006 - 10:25 AM.

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#10 Laurent Andrieux

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Posted 20 April 2006 - 08:31 AM

They are two ways a breaker will break :

1 - You are clearly pulling out too much current. It then break very quickly.

2 - You are pulling out slightly a bit too much. It then breaks after sometimes. Yes, it's like it would be heating, and it will not, therefore, restart quickly. In this situation, if you wait awhile so that it cools down and you can plug things back again, it might heat faster than it did when you first plugged things, so that it will break faster than it did the first time. It may be what occured. If you pulled 11 amp from a 10 amp circuit, this is what can happen.

Notice that the time it cools down gives you the opportunity to find out where you overload and correct this ;)

About reflections : depending on the "background (what you see through the window), in some situation (sky, clouds...) the use of a pola can be usefull but mind that it could cut off your reflexion and not the background, in some situations...
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