85 vs. 85B filter

[Andrew Karlsruher]

What is the difference between an 85 filter and an 85B filter? From the information I can gather, both correct daylight to incandescent light sources. Thanks for the help, this has been itching me for a while.

 

Andrew

[David Mullen ASC]

The 85 filter is for Type A film and corrects 5500K daylight for shooting on film stock balanced for 3400K. Type A film was invented for people shooting under 3400K lighting like from photoflood bulbs.

 

The 85B filter is for Type B film and corrects 5500K daylight for shooting on film stock balanced for 3200K.

 

So the 85 filter is slightly less warm than an 85B filter, not enough of a difference to really matter when shooting color negative, but for color reversal, especially for direct projection, it is more important to use the correct filter unless you want a cooler bias to the image for creative reasons, or to compensate for warmer sunlight.

[Laurent Andrieux]

And for some reasons that I don't know, DPs use the 85 filter a lot more commonly than the 85 B, though tungsten negative film is balanced for 3200 K. The neutral density combined conversion filters series are commonly based on a 85 conversion filter as well.

 

Is it for getting a bit more light since the 85 filters a bit less light than the 85B (though they both need a 2/3 stop compensation) ?

 

Is it an historical reason ?

[Sam Wells]

What is the difference between an 85 filter and an 85B filter? Andrew

 

About 1 printer light point or so, I'd think. Kinda trivial.

 

-Sam

[David Mullen ASC]

And for some reasons that I don't know, DPs use the 85 filter a lot more commonly than the 85 B, though tungsten negative film is balanced for 3200 K. The neutral density combined conversion filters series are commonly based on a 85 conversion filter as well.

 

Is it for getting a bit more light since the 85 filters a bit less light than the 85B (though they both need a 2/3 stop compensation) ?

 

Is it an historical reason ?

 

I think a lot of people use the 85B filter but just call it an "85" -- to the point where they would get confused if you corrected them.

[Andrew Karlsruher]

I think a lot of people use the 85B filter but just call it an "85" -- to the point where they would get confused if you corrected them.

 

Thanks a lot for the info. I asked many people the question before posting here, DP's who shoot film on a regular basis, and none really understood my question. It seems to me like the two are interchangable in most people's eyes or they think one is a nickname for the other. Take care,

 

Andrew

[Andrew Karlsruher]

Sorry to digress, but doesn anybody know the reflectance of snow? Is it in the IX, X zone? Just trying to do some Spot Meter conversions. Thanks a lot.

 

A

[Laurent Andrieux]

I think a lot of people use the 85B filter but just call it an "85" -- to the point where they would get confused if you corrected them.

 

Not sure... We use series that are : 85, 85 N3, 85 N6, 85 N9, 81 EF most of the time and I had the opportunity of comparing with a true 85B, the so-called "85" was less orange and less dense, but I'll ask people at Panavision to see if what they rent as an 85 is actually a 85 B... ;)

 

Sorry to digress, but doesn anybody know the reflectance of snow? Is it in the IX, X zone? Just trying to do some Spot Meter conversions. Thanks a lot.

 

A

Plesase, please, please...

 

Create your own topic,don't digress !!!

[Matthew Buick]

Am I right in thinking that only an 85B will work with 7280, yet all Super 8 Cameras only come with an 85.

[Mark Williams]

If you were using tungsten balance film (3200) AND you wanted to correct it to 5500k equivilent to daylight balanced film you would use an 85b filter..

 

If you were using tungsten balance film (3200) AND you wanted to correct it to 5000k you would use an 85 filter..

[Alex Wuijts]

If you were using tungsten balance film (3200) AND you wanted to correct it to 5500k equivilent to daylight balanced film you would use an 85b filter..

 

If you were using tungsten balance film (3200) AND you wanted to correct it to 5000k you would use an 85 filter..

 

that's confusing, because you don't correct the film, you correct the cooler light with a warmer gel. It works just the same ofcourse, but it sounds counterintuitive.

[Mark Williams]

I think a lot of people use the 85B filter but just call it an "85" -- to the point where they would get confused if you corrected them.

 

What confuses me, although I think Im right in saying that an 85ND.3 OR 85ND.6 ect is equal to 85B and not an 85

[Laurent Andrieux]

You mean the 85 would not be a 85 B but the 85 N3, N6 etc. would actually be 85B N3, N6 etc. ?

[John Holland]

Sorry but every time i post on here , must seem a boring old fart ,but this 85, 85b ,85nd6 is just so basic , i cant belive people are still asking such silly questions . John Holland , London.

[Mark Williams]

You mean the 85 would not be a 85 B but the 85 N3, N6 etc. would actually be 85B N3, N6 etc. ?

Yes although why its done that way I don't know.. Would be better just to say 85b n3 etc.

[Matt Sandstrom]

people are still asking

nope, they just started. it's you who's getting old. ;-)

 

/matt

[Jonathan Bowerbank]

Sorry but every time i post on here , must seem a boring old fart ,but this 85, 85b ,85nd6 is just so basic , i cant belive people are still asking such silly questions . John Holland , London.

 

Here here John

 

The difference between 85 & 85B isn't how much light it's allowing into the lens, it's a difference in color temperature...a very slight difference, but a difference nonetheless. Filters can offer a different color conversion yet still have the same transmission, as these do

 

:)

[John Holland]

Yes i did say boring old fart , but i did know this sought of thing when i was 14 at school , making 8mm films for the cine club , i found out the basics , from Kodak , books ,and trying things out , not expecting answer fro people ,on the other end of my computer , lazy , { no computers then } John Holland. London

[Mark Williams]

Here here John

 

The difference between 85 & 85B isn't how much light it's allowing into the lens, it's a difference in color temperature...a very slight difference, but a difference nonetheless. Filters can offer a different color conversion yet still have the same transmission, as these do

 

:)

 

Back to school then? Yes theres a 500k difference in the colour temp and actually it makes a noticeable difference something that should be understood and controlled. AS for lowering light values where does that get mentioned? ALL thats being discussed is what colour temperature is an 85nd.03 filter etc because these filters are I believe 131 mired.. NOT 112 mired as an 85 filter is

[Jonathan Bowerbank]

Is it for getting a bit more light since the 85 filters a bit less light than the 85B (though they both need a 2/3 stop compensation) ?

 

Sorry, I should have specified that I was referring to Laurent's post about the filters transmission %

 

:)

[Sam Wells]

In practical terms the difference is slight because in correcting from daylight in the everyday world it's not exactly the same thing as a 5600K standard of "photographic daylight" -- it changes throughout the day, it's contingent on the ratio of direct sunlight (warmer than 5600) and skylight (which can go to 12,000K or higher); alititude, latitude and so on.

 

To put it another way, a colorist just brushes the trackball and an 85B turns into an 85 in a wink !

 

-Sam

[Mark Williams]

o put it another way, a colorist just brushes the trackball and an 85B turns into an 85 in a wink !

 

-Sam

Yes but I think its best to know what is happening and why not put the correct filter in at the time? If you have it there.. If your trying to create a certain look perhaps your lighting other stuff at different colour temperatures and the colourist will correct one while then influencing your choices?

[David Mullen ASC]

Yes but I think its best to know what is happening and why not put the correct filter in at the time? If you have it there.. If your trying to create a certain look perhaps your lighting other stuff at different colour temperatures and the colourist will correct one while then influencing your choices?

 

Since daylight shifts in color temp all day long, there isn't much of a practical difference between the 85 and 85B because some adjustment -- more or less warmth -- will be needed for some of the footage at some point. It matters more if you are shooting color reversal for direct projection with no color-correction step and need to be very accurate with the color effect you want.