1970s movies and Tungsten Film

[Duncan Corbin]

So many movies were shot on Tungsten film during the 1970s yet most of them take place outside, so why not use daylight balanced film? 

[Charles MacDonald]

stick on an 85 filter and you are good to go.  small exposure penalty.

if you have to shoot daylight film under tungsten, the needed filter has a several stop penalty

I believe that the manufacturers could get better grain results by making the film tungsten balanced.

 

[David Mullen ASC]

43 minutes ago, Duncan Corbin said:

So many movies were shot on Tungsten film during the 1970s yet most of them take place outside, so why not use daylight balanced film? 

35mm motion picture color negative film was only tungsten-balanced from 1952 to 1986 because there was only one stock at a time, other than during the overlaps with the next generation. It wasn't until the 1980s that there was more than one type of movie color negative stock available. And if you are only going to have one, to convert tungsten stock for daylight you need an 85B filter, which loses 2/3-stop, but to convert daylight stock to tungsten, you need an 80A filter, which loses 2-stops of light.  Still camera color negative stock, however, was daylight-balanced because daylight flashbulbs were used inside.

The first Kodak color negative stock, 1950-1952, was daylight-balanced because 3-strip Technicolor was daylight-balanced, but in 1952, 3-strip converted to tungsten balance and so did Kodak.  The slow speed of the 3-strip process when it first appeared in the mid-1930's required daylight carbon arc lighting to get enough exposure.  Besides, silver is naturally more sensitive to bluer wavelengths -- to make a color stock balanced for tungsten, you basically make the blue layer faster to compensate for the lower level of blue wavelengths. But it is easier to light sets with tungsten lamps, hence why Hollywood wanted color negative film to be tungsten-balanced in the 1950s -- lighting everything with carbon arcs was difficult.

[David Mullen ASC]

It was the movie "The Greatest Show on Earth" that pushed the switchover in 3-strip from daylight to tungsten (and they made the process faster as well, probably jumped from around 10 ASA to 16 ASA) -- Goerge Barnes, ASC had to light the Barnum and Bailey Big Tent for 3-strip but since using open flame arcs was illegal in circus tents (open flames of any kind were), he asked Technicolor to switch the balance to tungsten.

[Karim D. Ghantous]

You learn something every day! Thanks for asking the question, Duncan, because it never would occur to me to ask it. And of course thanks to David for the detailed response.

Film stocks make cinema that much more interesting. More than lenses, even.

[Jarin Blaschke]

On 6/20/2020 at 4:30 AM, David Mullen ASC said:

35mm motion picture color negative film was only tungsten-balanced from 1952 to 1986 because there was only one stock at a time, other than during the overlaps with the next generation. It wasn't until the 1980s that there was more than one type of movie color negative stock available. And if you are only going to have one, to convert tungsten stock for daylight you need an 85B filter, which loses 2/3-stop, but to convert daylight stock to tungsten, you need an 80A filter, which loses 2-stops of light.  Still camera color negative stock, however, was daylight-balanced because daylight flashbulbs were used inside.

The first Kodak color negative stock, 1950-1952, was daylight-balanced because 3-strip Technicolor was daylight-balanced, but in 1952, 3-strip converted to tungsten balance and so did Kodak.  The slow speed of the 3-strip process when it first appeared in the mid-1930's required daylight carbon arc lighting to get enough exposure.  Besides, silver is naturally more sensitive to bluer wavelengths -- to make a color stock balanced for tungsten, you basically make the blue layer faster to compensate for the lower level of blue wavelengths. But it is easier to light sets with tungsten lamps, hence why Hollywood wanted color negative film to be tungsten-balanced in the 1950s -- lighting everything with carbon arcs was difficult.

Well, since film naturally sees blue more readily, you could argue that a tungsten stock is a more “native” stock: the longer the wavelength, the more sensitization you need.

I would hypothesize that a daylight stock needs extra sensitization for red, and to a lesser extent, green, rather than the other way around.

In this theory, a tungsten stock naturally “sees” more blue than a daylight stock, and overexposes blue in daylight conditions. A daylight stock has to work harder To boost red and green to balance the color for a given speed.

The fact that 5207 (250D) is a grainier and softer stock than 5213 (200T) might be evidence of this.

?

 

jarin

 

[David Mullen ASC]

However you slice it, daylight stocks need a slower blue record relative to the red and green record, whether that means that the blue layer is slower or the red and green layers are faster.  And certainly the blue record has to be much faster in tungsten light because of the lack of blue exposure.

The finest-grained blues come from using 50D stock but of course, it is slower in every layer!

I think this chart suggests that tungsten is deficient in blue whereas daylight is more evenly balanced in red to blue.