Bleach Bypass on the IP

[Jake Pollock]

hello all,

 

just finished printing a 15min 35mm short that's being printed with bleach bypass. we're looking to do an ip/in combo, but i'm not sure if we bleach bypass the ip if there are any archival issues to be aware of? any experience in the matter would be most appreciated.

 

cheers,

jake pollock

taipei, taiwan

[David Mullen ASC]

No, not really -- other than if you consider the IP to be your protection copy for the original negative, you should also make an IP that is normal, not bleach-bypassed. But otherwise, the original negative is archival and there shouldn't be storage problems with the bleach-bypassed IP either.

 

Maybe John or Dominic know otherwise though... I shouldn't think that leaving the silver on the IP would present a long-term storage issue, not compared to some of the issues of cross-processing a reversal stock.

[Dominic Case]

There is no evidence that I know of, that suggests a bleach-bypassed IP would have archival longevity problems. Silver is stable. But archivists would want the boot to be on the other foot: there needs to be certainty. I don't think a lab would guarantee no problems, and I'm sure John would say the same on Kodak's behalf. It's a non-standard process.

 

But anyway, don't regard a bleach bypassed IP as your archival master. It's not a true representation of the original neg, however long it lasts.

[John Pytlak RIP]

There is no evidence that I know of, that suggests a bleach-bypassed IP would have archival longevity problems. Silver is stable. But archivists would want the boot to be on the other foot: there needs to be certainty. I don't think a lab would guarantee no problems, and I'm sure John would say the same on Kodak's behalf. It's a non-standard process.

 

But anyway, don't regard a bleach bypassed IP as your archival master. It's not a true representation of the original neg, however long it lasts.

<{POST_SNAPBACK}>

 

I agree with Dominic. Bleach bypass is a NON-STANDARD process, and so has not been thoroughly tested by Kodak. I suspect there would not be a problem, as long as the film was completely washed to archival specifications, but without testing, I cannot say for certain.

 

As David mentions, non-standard processes can be problematic, such as his example of cross-processing certain reversal films in an ECN-2 negative process. Since some reversal film dyes require formalin stabilizer, the dyes will begin to fade soon after processing in the ECN-2 process which normally does not have a formalin stabilizer.

 

A "silver retention" print that is developed in a way to leave silver in the image is more prone to heat damage or heat-related "focus flutter", since the silver absorbs much more infrared energy than dyes. Athough not a problem in most theatres, really large lamps, poor heat filtration, or misalignment of the xenon lamphouse is more likely to cause a problem with these prints.

[Alberto Larios-Saavedra]

Regarding this issue, if I want to do Skip Bleach to the IP, when filming, should I underexpose the image by 1 full stop? I've heard you are supposed to when skip-bleaching the negative. Or should I expose normally since I wouldn't be skip-bleaching the negative? I've never done it and I might do some tests.

 

Thanks,

[John Pytlak RIP]

Regarding this issue, if I want to do Skip Bleach to the IP, when filming, should I underexpose the image by 1 full stop?  I've heard you are supposed to when skip-bleaching the negative.  Or should I expose normally since I wouldn't be skip-bleaching the negative?  I've never done it and I might do some tests.

 

Thanks,

<{POST_SNAPBACK}>

 

If you skip bleach the IP, you would usually expose the negative normally. Leaving silver in the IP would mostly affect the shadow densities in the final prints.

[Alberto Larios-Saavedra]

If you skip bleach the IP, you would usually expose the negative normally.  Leaving silver in the IP would mostly affect the shadow densities in the final prints.

<{POST_SNAPBACK}>

 

 

Thank you for your prompt response, as always.

 

Cheers,

[David Mullen ASC]

John is correct (of course). Leaving the silver in the negative increases its density in the highlights (where there is the most silve, then dye), as if you had overexposed it, unless you compensate by underexposing.

 

Leaving silver in the positive (IP or print) increases the density of the shadows (where there is the most silver, then dye.) If necessary, the most you may do is make the print a few points brighter to bring up some more shadow detail, but this will also lighten the highlights. Expose the negative normally -- if anything, add more fill or flash the negative, overexpose and pull-process, or use a low-con negative to improve shadow detail on the negative and therefore on the skip-bleached IP or print.

[Dominic Case]

Expose the neg normally.

 

THe lab will have to "underexpose" the IP when they skip-bleach it, for exactly the same reason that you would underexpose your camera neg if you were skip bleaching that. If they don't, the IP will be so thick that they won't be able to print a Dupe Neg from it. But that is something the lab has to take care of: it shouldn't be a matter of grading the neg light in order to achieve that result, you should be able to approve a normal grade (timing), then let the lab alter the printing set-up to suit the special process.

 

Skip bleaching the IP looks a little different from skip bleaching the neg. IT affects the shadows rather than the highlights, and will desaturate the darker colours and make them very subued: less contrast increase than the neg, but more than if you just skip bleach the print. be sure to see a test before you approve them going ahead with the whole job.