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  1. #21

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    PE enr is the acronym of the inventor ERNESTO NOVELLI RIMO ...here in rome ..at techincolor lab..with the collaboration of the great cinematographer VITTORIO STORARO

  2. #22
    Photo Engineer's Avatar
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    Dan;

    The two processes that I described in an earlier post here were well known at Kodak for years as REHAL processes. We used them as analytical tools to compare silver developed to dye formed and to determine the maximum amount of dye that could be formed. It was adapted for cienematography. We also used this type of process in making color prints to increase contrast. I have run it many times myself but we never used the acronym ENR for this process.

    I do seem to remember an ENR film or something in the 60s though, but as I said, this is vague to me. There were so many EN prefixes we used at Kodak for Eastman Negative products and EP for Eastman Print products that it is getting hazy at this date.

    It may be that this process was discovered by several people at about the same time, or not, but the popularization of ENR in the motion picture industry has probably firmed up that acronym. It is still REHAL at Kodak.

    PE

  3. #23
    mikemarcus's Avatar
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    The process described by Photo Engineer is not ENR (although it sounds like an interesting alternative to bleach bypass with greater control).

    From reading around, it seems that ENR uses the latent image of undeveloped silver halides which survive the bleaching process. These exposed silver halides are mixed with unexposed halides during bleaching to create similar conditions to that in the original exposed film. However as the film has already been through colour dev, the emulsion contains image dyes. The film is then either partially or completely redeveloped in black and white chemistry to superimpose a controlable density of silver onto the dye image before being fixed to remove all remaining halides.

    The process is as follows:

    Colour dev
    Bleach
    Wash
    B&W dev
    Stop
    Fix
    Wash
    Stabilise

    This is a proprietary Technicolor service which explains the lack of reliable information. It is designed to be applied to only the positive print or interpositive and in this sense differs from bleach bypass which is applied to either the camera negative, positive print or intermediate depending on requirements.

    I conducted tests yesterday which suggest that ENR has no effect on C41 negatives although more experimentation is needed to be sure of this conclusion.

  4. #24
    Photo Engineer's Avatar
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    Mike;

    A bleach following a color developer, if powerful enough to bleach the silver, will result in 2 things. First, carryover of color developer into a bleach will cause an instant veil of fog to form via oxidation of the color developing agent by the bleach. Therefore, a clearing bath would have to be used between the two baths as well as a wash to remove the clearing bath.

    Second, the bleach, if powerful enough to bleach color developed silver would be strong enough to bleach the latent image in most cases. We had to be careful of that in our experiments into catalytic image amplification. See the patents by Bissonette et. al. on this subject. It is very sticky and hard to pin down exactly how much latent image is left after the first development. Usually it is considered that there is none left, since if it is a latent image, it develops.

    In fact, the B&W development is usually considered to develop all of the silver that the color development woud have, and therefore it is equivalent to bleach bypass.

    Lastly, the lack of a fix after the color developer or bleach would probably lead to bad fog in any case.

    I'm sure it must work, but that there are missing steps and a lot of misunderstandings over the process cycle you describe.

    PE

  5. #25
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    In Romania, by the year 1974 was a process GRAFIS COLOR - process for color print Orwo PC 7.
    It consists for using a color developer more diluted (I think about 20%) and a partial bleaching. The images were obtained desaturate. The partial removal of silver, we obtain a good level of black.
    By 1994 I know that there was a movie " Pepe & Fifi" using this method http://www.cinemarx.ro/filme/Pepe-38...ifi-70940.html. Color print used was Kodak 5386. I remember they were trouble to scan a picture of the color print. Containing color images and metallic silver - sure to be problems with scanning.
    By 1984 I did some tests - mixing color image and b & w on color print. The effect obtained was a partial color image. It can adjust the weighting of each image (color and b & w). Work with color negative and a dupe negative b & w (DP 3 - DN2 Orwo) made from color negative. Color positive process was classic ECP 2.
    My opinion is that applying a particular technique to a negative film is a bit hazardous.
    It is more lucrative to apply to positive film.
    George

  6. #26
    zsas's Avatar
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    More Bleach Bypass Details Needed

    I am going to be messing around with the below while using color negative film:

    Quote Originally Posted by Photo Engineer View Post
    There are two common processes that use either retained silver or augmented dye images to get odd effects in color. They are:

    Color develop
    stop
    wash
    fix
    wash
    rehal bleach (ferricyanide + bromide)
    clear - stop + sulfite
    wash
    fog with light
    EITHER: color develop or B&W develop depending on effect desired
    wash
    fix
    wash
    stabilze

    One process will accentuate color and contrast and the other will give you an intense bleach bypass look.

    The sequence with two color developers can be repeated as often as desired to get higher and higher color saturation and contrast.

    PE

    Lets break this down some more as I have some questions....

    BEGIN, as per PE:

    Color develop
    stop
    wash
    fix
    wash
    rehal bleach (ferricyanide + bromide)
    clear - stop + sulfite

    STOP THERE FOR A SECOND....
    What is this? I normally use water for my B/W stop bath so I dont have this on hand, what do I need, say Kodak Indicator Stop Bath For Black & White Films?

    CONTINUE as per PE.....
    wash
    fog with light

    STOP THERE FOR A SECOND....
    What???

    Lets suppose I have a Patterson tank with 1 roll of 35mm in the tank. Do I open the tank, pull the film off the plastic reel with the film head in one hand and tail in the other and hold it up to the lightbulb? For how long, a few seconds?

    Then what? Load the wet film back on the pastic real? I suppose I can do it in light now?

    CONTINUE as per PE.....
    EITHER: color develop or B&W develop depending on effect desired
    wash
    fix

    STOP THERE FOR A SECOND....
    The C-41 fixer or the b/w fixer or does it matter?

    CONTINUE as per PE.....
    wash
    stabilze

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