85B Warming Filter for B&W?

[Nomad Z]

I have an 85B warming filter that I picked up cheap. It's got a sort of orangey colour - will it work like an orange filter with B&W film?

If it helps, I'm thinking of using it this weekend with some Legacy Pro 400 and Rollei Retro 400S.

 

[Ronald M]

nothing like trying it out. All filters pass their color and block those with wave lengths that are different. It will darken real blue sky. not pastel blue ones like normally seen.

Green foliage will go darker.

Finding the proper filter factor is important. Expose a grey card properly in full sun and then add the filter & open the lens 1, 1.5, 2, 2.5 stops. The proper filter factor will make the grey card the same density. Do not change shutter speed.

Repeat for tungsten light if you wish to use it there. Filter factors are different.

 

[Roger Hicks]

Yes, it will work like a very weak orange filter.

Cheers,

R.

 

[Nomad Z]

Thanks, chaps. Apparently, it's a colour conversion filter, with a factor of 1.6 according to here...

http://en.wikipedia.org/wiki/Filter_factor

A smidge over 2/3rds of a stop, so opening a stop should about do it.