Desaturation techniques

Jarin Blaschke · January 27, 2004

I have a shoot in a couple months with many night driving scenes along deserted roads. I want these scenes to look dark and quite desaturated - as things truly look to your eye in really low light - not simply blue as treated in most films. The dark part I can do - but I'm wondering how to selectively desaturate certain scenes in an organic way, should the film ever make it to print.

I believe I once read about a desaturation filter made by Tiffen that was yellow-green in color and when combined with counteractive timing, would kill color - I would expect some more than others (blue and magenta). Does this exist? Does anyone have experience with it? How much desaturation can I anticipate? Do other brands make a similar product (esp. Schneider)? Would it be worthwile to test black and white filters - or would you anticipate them to be too strong? Also, when making such hefty timing adjustments after shooting through such a filter, might there be significant color crossover from highlights to mids to shadows?

The only other option I could concieve of would be an ENR treatment to the negative of these certain night scenes. As I understand, this process adds some film speed so I could then pull-process to keep the contrast more manageable after adding silver to the image. Am I correct in understanding that the ENR mostly affects the upper areas of the curve, pushing them higher, and a pull-development also works hardest in this area, holding it down somewhat, although probably not enough to restore normal contrast? Is ENR available for negative processing, or only the hefty bleach-bypass?

Also, because the scenes are so dark, most of the information will lie in the low to mid areas of the curve with occasional highlights like headlights. Would ENR do much work with such a negative?

A part of me also wonders if a negative ENR might affect the look too much (adding sharpness as well as punch) - it still needs to cut with the rest of the film.

Obviously I will push for a good batch of tests, but as usual I'm sure these will be limited (low budget 35mm). I'd greatly appreciate anyone's experience/opinions/expertise. Thanks.

-Jarin

Alvin Pingol · January 28, 2004

There are many different ways to achieve a desaturated look onscreen. In an article for Northfork, our very own David Mullen mentions different ways he desaturated the image. The article can be found on Cinematography.com under "Featured Articles." In the past, he has posted a lot about this, as well. This is his post from the 2002 archives:

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This is something I've posted in the past, but rather than force you to hunt through the archives, here it is again.

HOW TO DESATURATE COLOR

The various methods used to achieve desaturation of color in motion picture photography are:

- Art direction. The best way to control color is by using less color in costumes, set dressing, wall painting, etc.

- Use a less saturated film stock. There are basically four: Fuji F-400T, Kodak Vision 320T, Expression 500T, and 5263; these have a subdued color palette. NOTE: there is generally a correlation between lower saturation and lower contrast and softer blacks, since the black density can affect how saturated we perceive a color to be (just as in painting - to make a color more pastel, we mix white into it.)

- Filters. Filters that allow bright highlights to bleed or wash into the shadows not only lower contrast, but soften colors. Some types of light-scattering filters: ProMist, Fog, Double Fog, Low Contrast, UltraCons.

- Smoke. Smoke has a similar effect to filters in that contrast and color are lowered because light is allowed to wash over everything. However, smoke is dimensional and affects objects in the background more than objects in the foreground due to the increasing density of the smoke that one is viewing the object through as it recedes from the camera position.

- Lighting. The general rule is that frontal lighting emphasizes color; back or cross-lighting emphasizes texture.

- Developing. Pull-process developing can lower saturation a little, but is mostly used to lower contrast, especially when combined with silver-retention printing.

- Flashing. Again, like filters, flashing lowers color saturation by adding a wash of white light over the image, also lowering the contrast. The advantage of flashing over filters is that it doesn't soften definition or produce artifacts like halos around light sources. Flashing can be achieved through the lens using a VariCon (which fits into a 6x6 mattebox) or a Panaflasher (which fits over one of the magazine ports on a Panaflex.) Some labs will post-flash the negative before development but most do not like to get into this because of the chance of ruining the negative through over-handling. Prints can also be flashed, which lowers contrast by darkening the white highlights ? it also slightly softens colors but not as much as negative flashing.

- Exposure. Underexposure is not really recommended, but a thin negative printed up will generally produce weak colors and blacks, plus show a lot more grain. Some slight overexposure usually increases saturation if the denser negative leads to printing down the image ? but extreme overexposure will also wash out colors (and highlight detail unfortunately.)

- Silver-retention processes. Generally done to the print, but some techniques can be applied to the negative. A certain amount of black silver normally removed in the developing process is left in the image, increasing contrast and blacks, but also softening colors. "Skip-bleach" or "bleach-bypass", CFI's "Silver-Tint", and Deluxe's "CCE" process are the most extreme techniques, leaving most of the silver in the print; Technicolor's ENR and Deluxe's ACE processes are more subtle, allowing the degree of silver retention to be modified. Often a color saturation and contrast-lowering technique like flashing or filtration is used in conjunction with a silver retention process for the prints to return the black levels to normal or higher but also desaturate the image even further.

- Optical printing. From the original color negative, both a color I.P. and a b&w positive is struck and then both elements are recombined to create a new, desaturated dupe negative. How desaturated the image is depends on what percentage of the total exposure came from the b&w or the color I.P. "The Sacrifice" and "Sofie's Choices" (the flashbacks) used this technique; more subtlely, so did the opening scenes of "The Natural", which rephotographed the color image out-of-focus over the sharp b&w image, creating a diffusion effect.

- Telecine and digital effects. Color is easily manipulated in telecine transfers or using digital scanning. "Breaking the Waves" scanned the movie into PAL D-1 tape and desaturated the colors and scanned back to film but at video resolution. Branaugh's "Frankenstein" digitally scanned the North Pole sequence into a computer and desaturated the image and output it back to film at full 35mm resolution. "Digital intermediate" is expensive but the most flexible way of lowering color saturation while controlling blacks. "O Brother Where Art Thou?" manipulated its color in this manner.

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All of these techniques can be combined in various ways ? and usually are. Most productions trying to create a softer color palette always begin with the art direction and costuming. One reason if that it is always better to use the simplest means to achieve a goal. Another is that primary colors tend to desaturate less noticeably than pastel colors when using some sort of desaturation technique ? and since skintones are generally pastel, they will lose their color much faster than a primary color in the frame. So controlling those colors is very important.

Some people combine a contrast / color lowering technique like flashing, and then use a silver retention printing technique to restore the blacks in the prints.

Some examples of these techniques in use:

"Saving Private Ryan" was shot on 5293 pushed one stop to 400 ASA, flashed with a Panaflasher (generally), and used the ENR process on the prints. Some shots used filters or just foggy skies to wash out the image, plus the lens were stripped of their coatings to increase flare, and of course, the subject matter was naturally low in color saturation. See "American Cinematographer", August '98.

Looking at DP Darius Khondji?s work, we see that "Seven" used negative flashing combined with Deluxe's CCE printing process. "Evita" used a VariCon and diffusion filters combined with a 30% ENR printing. ?Alien Resurrection? used a 50% ENR printing.

"Ronin" used pull-processing of the neg combined with CCE printing.

?Heaven?s Gate? used negative flashing and print flashing together to soften the colors and contrast ? plus a lot of smoke and dust in the scenes. ?McCabe and Mrs. Miller?, also shot by DP Vilmos Zsigmond, used underexposure, push-processing, negative flashing, and diffusion filters (mostly Double-Fogs).

?Kansas City? used Kodak?s EXR 5287 stock combined with CCE printing. (5287 has since been updated to 5277.)

?High Art? was shot on Kodak?s VISION 320T (5277) and flashed with a VariCon ? but no silver retention printing techniques were used.

?Payback?, used the CCE printing process, combined with shooting without the 85 filter outdoors on tungsten stock, and using a blue filter indoors ? the blue-bias on the negative ensured that skintones would be consistently desaturated. This was combined with careful color control in the art direction ? even yellow taxis and red fire hydrants were painted down. The print was timed to the blue side to keep any reds from becoming more saturated.

"Minority Report" used a skip-bleach process to the negative.

"O Brother Where Art Thou?" used a digital intermediate.

All of these films also controlled color through art direction.

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David Rolston · February 7, 2004

I'm curious if anyone knows the specific process that was used in John Boorman's The General.

David Mullen ASC · February 7, 2004

"The General" wasn't just desaturated -- it was entirely b&w. It was shot on color negative and duped to a b&w intermediate.

David Rolston · February 8, 2004

"The General" wasn't just desaturated -- it was entirely b&w. It was shot on color negative and duped to a b&w intermediate.

I know it was released in the B&W form, but the DVD has a desaturated version. When you say "Intermediate" do you mean a black and white Interpositive?

David Mullen ASC · February 8, 2004

If the DVD has a desaturated color version, that would have been easily done in the color-correction session when transferring the movie to video.

The film was shot in Super-35 and blown-up to scope. They probably make a color-timed Super-35 color interpositive (I.P.) from the negative. Then the S-35 I.P. was cropped and stretched to a 35mm anamorphic I.N. -- except in this case, a b&w duplicating stock was used instead of a color one for the dupe negative.

The other scenario is that it was copied to a S-35 b&w positive from the S-35 negative, but that's a little trickier to color-time so I suspect the switch to b&w happened when making the I.N. from the I.P.

February 1, 2006

Thanks to Mr. Mullen for your vast insight to these different films and techniques. I was glad to be reading this article while watching Sophie's Choice.

I am looking into the B&W and color mixing in the print and am wondering if this process is affordable (on a low budget) and if it is possible/easy to change the level of desaturation scene by scene for a final print. The film I'm working on I want to start very saturated and take out the color almost completely by the end. (I want to avoid a DI) Is this feasable on a low budget?

Thanks again.

Chris

Leo Anthony Vale · February 1, 2006

- Optical printing. From the original color negative, both a color I.P. and a b&w positive is struck and then both elements are recombined to create a new, desaturated dupe negative. How desaturated the image is depends on what percentage of the total exposure came from the b&w or the color I.P. "The Sacrifice" and "Sofie's Choices" (the flashbacks) used this technique; more subtlely, so did the opening scenes of "The Natural", which rephotographed the color image out-of-focus over the sharp b&w image, creating a diffusion effect.

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---'Reflection's in aGolden Eye' and 'Deliverence' were originally released this way.

Though by combining the OCN and a B/W dupe neg.

Both films were technicolor, 'Reflections..' printed onto matrices for IB, 'Deliverence' , most likely,onto a CRI.

There was an SMPTE article about 'Reflections...', an AC article about the production of "Deliverence'.

I sure remember that film as greyish.

---LV

David Mullen ASC · February 1, 2006

I have this discussion all the time with directors. If you do a D.I., then gradual or sporadic desaturation is very easy. If you don't do a D.I. and have to go to print, it's extremely hard because it has to be built into the negative.

ENR is a print-only process; the method of doing it to the negative is bleach-bypass and it's not adjustable in strength in the same way that ENR is. For most labs, it's all or nothing -- all the silver is left in the image or it is removed completely (i.e. normal processing.) For a few labs, they can offer two levels of bleach-bypass strength.

Yes, combining it with pull-processing would help mitigate the build-up in density and contrast, but you still have to factor the increase in graininess from leaving silver in the image.

Plus it isn't cheap; most labs charge a $500 set-up fee everytime you drop-off footage to be skip-bleached in any way, plus charge 5 cents per foot extra on the processing. They make money after all on that silver they normally get to reclaim.

Of course, you can do very SUBTLE changes in saturation in the image through the methods I mentioned (art direction, foggy-type filters, smoke, low-con stock, etc.) but most of those techniques also soften the image and lift the blacks, so it won't match the other footage in those terms.

In other words, if you want to do an overall desaturation to an entire reel of a movie or the whole movie, that's not so hard, but to do it scene-by-scene without a D.I. is very difficult and makes a good argument for finding the money for a D.I.

The other technique is the one Sophie's Choice did using an optical printer, but then all of your desaturated shots are dupes. I suppose the other approach would be to do a D.I. just for those scenes and cut them into the rest of the movie.

February 2, 2006

Thank you for the answer to my question. One thing caught my attention, you mentioned an optical printing technique like the one in Sophie's Choice, but then you said it would have to be duped...I think you mean it has to be copied onto black and white stock as well....is that a big deal to do? Did you mention this because it will add more money to the cost (which seems like it would) how much more are we talking? Does it effect the look when you dupe like add more grain or more contrast or something?

Thanks for the help.

Chris

David Mullen ASC · February 2, 2006

You take the color negative and make a color I.P. and a b&w fine-grain positive off of the color neg. Then you optically print these two positives back onto a color I.N., and then you cut that color I.N. into the original neg. So you've got the costs of the color and b&w dupe stocks, plus the optical printer work.

FotoKem has a demo of this technique that they can screen for you if you're in Los Angeles. Talk to Mark Van Horne.

February 2, 2006

Thanks again.

Filip Plesha · February 4, 2006

You take the color negative and make a color I.P. and a b&w fine-grain positive off of the color neg. Then you optically print these two positives back onto a color I.N., and then you cut that color I.N. into the original neg. So you've got the costs of the color and b&w dupe stocks, plus the optical printer work.

FotoKem has a demo of this technique that they can screen for you if you're in Los Angeles. Talk to Mark Van Horne.

Why not cut the film in A and B rolls, and think of the desaturation scenes as just another optical like a transition. The black and white dupe negatives would be intercut with one of the rolls of original color negative.

When making a new IP, you could just redo those scenes as you would redo transitions in A/B cut films.

With instructions about the ratio of exposure for color and BW (for the desired amount of desaturation), it wouldn't be more complicated than redoing a simple cross-fade

audien

That would spare those scenes of two generations of grain and a noticable loss of resolution, because only BW dupes would go through aditional copying, the color neg image would still serve as a carrier of main detail.

But, then I'm just an overenthousiastic movie goer.

Edited February 4, 2006 by Filip Plesha

Leo Anthony Vale · February 4, 2006

Why not cut the film in A and B rolls, and think of the desaturation scenes as just another optical like a transition. The black and white dupe negatives would be intercut with one of the rolls of original color negative.
When making a new IP, you could just redo those scenes as you would redo transitions in A/B cut films.

With instructions about the ratio of exposure for color and BW (for the desired amount of desaturation), it wouldn't be more complicated than redoing a simple cross-fade

audien

That would spare those scenes of two generations of grain and a noticable loss of resolution, because only BW dupes would go through aditional copying, the color neg image would still serve as a carrier of main detail.

But, then I'm just an overenthousiastic movie goer.

Answer prints and I/Ps are usually made in a continuous contact printer. So registration is iffy.

The lab I worked at did make some prints from TC 3-strip negatives. But it wasn't always successful.

Maybe okay for TV, but for a big screen...

---LV

David Mullen ASC · February 4, 2006

Answer prints and I/Ps are usually made in a continuous contact printer. So registration is iffy.

The lab I worked at did make some prints from TC 3-strip negatives. But it wasn't always successful.

Maybe okay for TV, but for a big screen...

---LV

Also, I don't think double-exposing a color neg and b&w neg over each other using A-B rolls works the same way on the image as double-exposing positives to create a new negative. I could be wrong.

But, yes, I think the main problem would be registration.

Filip Plesha · February 4, 2006

Actually, you are right, the results would be different, because in one case you would be "freezing" highlights while shadows would "build up" with extra exposure, and in the other case, it would be vice versa, the highlights would "grow" faster with more exposure while shadows would be "frozen".

The result would be: if you used negative+negative onto positive, the negatives would serve each other as a SCI mask and there would be an increase in shadow contrast.

And if you used positive+positive onto negative, the highlight contrast would increase instead.

But either way you would get a desaturated image, just in two different flavours.

You could compensate the unintentional additive contrast masking my pulling the target stock in processing a bit.