Green, Blue Filters w/Portraits

[bvy]

I'm considering working with a green or blue filter with my portraits on Impossible Project 8x10 film. I'm using strobes, and most of my subjects are younger children, so I'm not so worried about enhancing blemishes. Rather, I'm interested in bringing out freckles and lightening the eyes. I've made portraits on ortho film, and I like the look of them. Any thoughts? Also, how could I meter for these when working with panchromatic material? Hold the filter over the light meter?

 

[Gerald C Koch]

An ortho film lacks red sensitivity. To better duplicate the look you need a minus red (cyan) filter not a blue or green one. A green filter will accentuate any skin defects and is usually used for masculine subjects (think of the Marlboro man). A blue filter would probably be too much. To calculate exposure you would use the filter factor for the particular filter used. When using color filters I would suggest becoming familiar with the color wheel. This chart will tell you immediately what colors are effected by a particular filter.

 

[DREW WILEY]

Ortho films were once popular for "rugged" shots of older men. A strong green filter on pan film will give an analogous result. Blue filters of equal intensity are going to be slower (denser) than equivalent green ones, so probably not practical. Different meters see hues differently. So I don't meter through the filter. I just use the recommended filter factor on the specific film Tech Sheet, then always test in advance before an important shoot. For example, a Hoya X1 (G) medium green filter requires two stops of extra exposure for most pan films. I don't think you'd need anything deeper than that for a pronounced effect. The weaker X0 yellow-green filter can also be useful in portraiture, and requires about one stop of compensation.

 

[bvy]

Good ideas. Thanks. I don't know that the IP film publishes a tech sheet -- I'd be curious to see curves and spectral response. Under strobes it seems quite easy to blow out skin tones (fair Caucasian skin, in particular). I like the idea of cyan, green or green-yellow filters to achieve some of the effects I mentioned, and maybe help control that.

 

[DREW WILEY]

Cyan filters are rare and expensive, and never see typical commercial usage. One problem is that it's hard to design a cyan filter that
doesn't easily fade, other than the non-image-forming dichroic type used in enlarger colorheads etc. A wonderful resource is the old Kodak
Wratten data book. I gave hundreds of spectrograms and other characteristics for their extensive Wratten filter line. Of course, many of these
were quite specialized, but there are analogous select types in coated glass from several mfgs for common uses, which often still reference
the old equivalent Wratten number.