Cinematography Mailing List - CML

Bleach Bypass


Does anyone out there have experience with any kind of bleach bypass process? I have been fascinated by this since reading AC's article on Seven, shot by Darius Khondji. I believe he used some variation on this process on Delicatessen, City of Lost Children, as well as Evita.

Kristian Bernier

I have run bleach bypass before. It's a nice idea. Basically, the color negative process uses a first developer to produce B&W images on all three color layers, formed from metallic silver just like with a B&W film. Then a color developer links dyes up in areas where there is a silver image, and that silver image is bleached out.

If you reduce or eliminate the bleach, you have a metallic silver B&W image superimposed on your color image. This gives you a nice pastel effect and it also gives you as much as a full stop more film speed. I have used it for documentary work in dark nightclubs where I needed the extra speed and rather liked the muted color effects.

Shoot a test roll! Try it! It's fun!

Scott Dorsey

Since this process is normally done to prints, it does not endanger the negative in any way - you always have the option of just making a normal print. So the bond companies shouldn't worry.

But perhaps this is why Storaro flashes his prints instead of the negative, as Khondji does, before the bleach-bypass. (Flashing a print also looks different.)

David Mullen

Even if you do a bleach bypass process on the original negative, the effect is not permanent. If you, (or the bond company bean counters) are unhappy with the "look" of the bleach bypass process, you can have the lab re-run the negative through the processor. This time bypassing the first developer, and going through the (previously skipped) bleach tank. This renders a normally processed and looking negative.

So, for once, you CAN have you cake and eat it too!

Bill Bennett

A couple of notes:

You do lose some colour saturation, which you might like, but you could test a light coral to restore a bit of flesh tone.

At the risk of sounding patronising, do let your production and costume designers know what you're planning, because the exposure threshold for darker tones is lifted appreciably, and those "subtle, dark colours" will be mostly, well, black...

A side-effect of the above quality is that incidental eyelights tend to disappear, especially in dark pupils, so unless you have an intentional source for the eye, focus sometimes seems questionable. I write as a focus puller who has had to draw attention to clothing, ears and hairlines in order to convince Production in rushes.

Nevertheless, I love it...

Sam Garwood

No BLEACH leaves all the silver image in the film as well as the dye image.

The end result is a denser image with all the colors and "bulletproof" blacks. The image is therefore very desaturated and more contrasty.

No bleach ACCELERATOR leaves half the silver image so its effect is not as pronounced.

These methods do not work well with IP stock.

The process should be applied to soft, muted-color, low contrast images.

Avoid maroons and navy blues because they will go black. (Unless, of course, you want this effect -- I have, sometimes.) Same thing with red lipstick/nail polish -- test it first! (Yeah, right, like there's ever any time.)

It helps to use diffusion during principal photography -- take a look at Evita -- you can see nets in the lens flares of some shots; a perfect example.


I just read the article in Lighting Dimensions and it was informative. I did find the part about the ENR process confusing though. It discussed the bleach bypass used in 'Seven' and the ENR used in 'Evita' as if they distinct and different processes. The article didn't go into details but it could refer to the fact that in 'Evita' he retained only about 30-40% of the silver versus the complete bypass in 'Seven'. Anybody have more info?

I also found interesting Darius comment about liking to keep his lighting sources as far away as possible for a more natural look. Common wisdom, at least in the commercial /music video world that comprises most of my work, is to get your sources as close to your subject as you can for that glowing soft wrap.


Basically bleach bypass is exactly that, 100% of the silver is left in the print, ENR is a variable process from 0% silver to 100% silver. Evita was 38%.

Geoff Boyle

I've just returned from Foto-kem's demo of their bleach bypass service.
An interesting demo, showing the results from b-b on the neg, the print, the IP, IN, and release print.

I'd like to hear from others who have used this (or other similar process, ie. ENR). Was the decision made in prep, or did you decide after the fact? If planned for, did you alter the shooting for this (ie. use low-cons, more saturated colors in art direction, etc.)? What would you do different next time? If anyone has knowledge of articles that would be helpful too, but I'd really like to hear first hand experiences.

Dave "it costs HOW much!?!" Trulli

Sorry to butt in here, but I checked out the Foto-Kem demo also. The presenters were ok, but we were stuck in a small screening room with the projector and four seats.

<<Did the bleach-bypass demo desaturate colors and increase contrast in an attractive way? Or did it just look harsh & grainy?>>

The contrast did go up. Way up on some cases. Regarding colors, sometime when looking at buildings it looked Black & White. At to harsh and grainy, I wouldn't say grainy, but I would say harsh.

<<Did they show any tests that were combined with flashing either the positive or the negative? Darius Khondji flashes his negatives / Storaro flashes his prints - in conjunction with ENR or bleach-bypassing.)>>

They didn't have any test involving flashing, sad to say. I found the whole process intriguing, but Foto-Kem's process bugs me because it's all or nothing.
With ENR you can dial in some degree of control. One process they showed that I like was that they made prints from prints. It gave this neat looking very contrasty, super saturated color feel. Could be used in a music video format.

Scott Spears

It's true, a bleach by-pass can desaturate colors and can make blacks look great, but it does increase the contrast and you can lose shadow detail.

Sometimes you can get the same results with a PARTIAL bleach bypass without the corresponding contrast gain and shadow loss. The partial bypass in combination with the proper timing and (if necessary) a pull process may allow one to have the best of all worlds.

Bob Lancaster
Alpha Cine Labs

The Foto-Kem demo was interesting. The look of bleach bypass is quite different depending on when you do it. All of the looks attained were interesting, but for feature type work I think b-b on the release prints was the most pleasing. Of course this is also the most expensive option. B-b on the negative was pretty strange, whites went neon white, like blown out video. Color saturation was lowest when done to the release print, highest when done to the negative.

The demo I saw did include flashing (10 + 20%) the neg. At 20% the blacks looked milky, 10% was closer to the look of b-b on the r-prints - but not that close. Unfortunately, the demo footage at this point was pretty high contrast already, it would've been interesting to see the effect with lower con stuff.

B-b in the IP or IN stage was closer to the look of b-b on the negative.

BTW, some of the footage used for the test is from a movie in production recently. They said that he wanted the r-prints bleach bypassed but the producers nixed the idea. Funny, though, I liked the normal footage best in this case. I'd like to hear the DP's thoughts sometime (I'll respect his privacy and not name names).

Gotta go.

Dave Trulli

Phil Burchell wrote:

>>As I understand it, the beauty is if you don't like the effect the Lab can re-bleach at a later time, taking it back to normal. Is this a major deal

True: but if you have modified your exposure (often necessary on BB processes) or ordered pull-processing, then you finish up with neither one thing nor the other. The process is simple - it's just the same as re-processing or "rewashing". Your lab will face exactly the same costs as for the first run through (i.e. normal developing).

In the case of BB prints, the lab needs to print them a bit under a stop lighter to balance the extra density of the silver. Once again, a rebleached print will be unacceptably light.

Still, if you can't use the BB'd reel, you can extract the silver from it and sell it.

>>I'd like to know how you'd do a partial bypass (sounds like heart surgery), and how to specify it to the lab (ie "in the soup half normal time"? ... or "20%"?).

How to specify it? - talk to your lab - every one will have a different approach.

Dominic Case
Atlab Australia

> SE7EN looked really good. It had saturation was really interesting and the blacks were black. How did Darius Khondji do it?? It seems he had the best of both worlds. Did he flash the neg.? I don't know, but I want to.

He shot "Seven" in Super35, mostly on 5293 pushed one stop; he also flashed the negative. Then the print was bleach-bypassed. I don't know if he rated the filmstock faster due to the push-developing, or if he left it at 200 ASA and just let the pushing add density. He said that the pushing increased saturation, while the flashing lowered it and the contrast, and the bleach-bypass added contrast and lowered saturation. He also used some 5287 for some night photography, and 5245 for the ending daylight scenes.

I think he might have used the Panaflasher for his flashing. (In "Evita", he used the Varicon; he did less pushing, used diffusion filters, shot in anamorphic, and used the ENR process.)

The studio wouldn't pay for all release prints of "Seven" to be bleach-bypassed, so after an initial print run for the major theaters, an I.P. was bleach-bypassed and more release prints were made from an I.N. struck from that.

David Mullen

Storaro has a different approach than Khondji - he goes for an over-exposed negative, processed normal, and uses the ENR process on his prints, which is capable of varying the degree of the re-silvering effect. He also flashes his prints, which softens the contrast by darkening the highlights, leaving the blacks very dark. He probably has to make a very light print as a starting point.

I've wanted to try any of these effects for years (assuming that it was right for the project), but the budgets of my films preclude any of this...

David Mullen

Bob Lancaster wrote :

> a bleach by-pass can desaturate colors and can make blacks look great, but it does increase the contrast and you can lose shadow detail.<

An interesting alternative to bleach-bypass is to strike two intermed positives, one in colour and one in b/w. By double-exposing the neg with different proportions of the two (otherwise identical) positives, you can achieve various degrees of colour desaturation without losing shadow detail or affecting the contrast... or so I've heard. Never had the chance to try it out myself. Anyone have first-hand experience?

Chris Rowe

Yes, we did it on sections of a remarkable Aussie film last year called "What I Have Written" shot by Dion Beebe ACS. The sections were actually also freeze frames, which took up about a third of the film.
(yes, yes, a la Chris Marker's La Jettee).

The result was an "almost black and white" look, with just faint hints of colour in some areas: occasionally flesh tones, a red scarf, a purple overcoat. The colours were all very dark and desaturated - very subtle. Of course, it's equally possible to go for a predominantly colour look by selecting a different percentage of b/w to colour.

The difficulty is that every shot needed a different proportion of b/w to colour to get a consistent look.

The good thing is that - with sufficient testing - you have that much control in post production.

Dominic Case
Atlab Australia

The process does not give as rich blacks as you would have with bleach bypass. As a matter of fact, I don't think the two systems are even comparible. The double-interpositive system gives a desaturated look but without as much increase in constrast and the blacks are not as rich.

Also, colours tend to react differently when combined with their black and white equivelants - this does not really happen with bleach bypass.

Jon Mendelssohn

we are about to finish a feature and use the Bleach By Pass (60%) process at the stage of the IP at Rank in London. It is not the same than ENR process that can be applied only on positive prints. The process will be used for about 60% of our film, the remaining part being printed normaly to IP. We've done tests and the result of the 60% Bleach By Pass looks great, but we've not tested yet how to intercut a regular IP with a Bleach By Pass IP. What if the director wants to dissolve from one to the other? can we A&B the two IPs to go to IN? What control must be done at the lab? Does anyone have experienced that process?

Georges Jardon, Postproduction Jardon et associée,

We used the Bleach bypass IP process for a feature recently: it's a good method as it's less savage than treating the original negative, while many distributors won't pay to treat every print. Best of both worlds. However, no-one sees the final results even at Answer Print off original neg stage - you have to wait for the dupe neg. And as for rushes/dailies . . . - we actually had one magazine set aside for a quick burst on every set-up, and that became a weekly test roll that went through the entire process. Meanwhile, telecine set up a transfer "look" that emulated the final Bleach Bypass result. It's now the only telecine in town that has a bleach bypass button;-)

Regarding your question: A lot depends on how your lab has set up the IP. Ideally, they have modified the printing exposure so that the BBIP has the same density and requires the same set-up to print back to DN as the plain regular IP. If that's the case, then you should have no trouble intercutting or even A/B dissolving the two IPs. Although remember that dissolves from positive behave slightly differently from dissolves from negative (in the way that highlights or shadows hang on or appear first, most noticeable in long dissolves). This might be significant given that you would be dissolving to or from a very high contrast image.

If the lab has not anticipated this, they may possibly have trouble mixing the two IPs. Talk to them NOW.

Out of interest, what provisions did you make in lighting, exposure, and wardrobe etc, for the bleach bypass effect. And what stock did you shoot? In our case, we found, in extensive testing by the DoP, that (a), some colours shifted a bit (she was using filtration as well, but the BB exaggerated its effect) and (b), that, using higher speed stocks, the grain blew up in some colours - particularly yellows.

Dominic Case
Atlab Australia


Copyright © CML. All rights reserved.