[Leica] gigabit film

[Johnny Deadman <john@pinkheadedbug.com>]

this was posted to rec.photo.darkroom recently, thought it would be of
interest to youse guys. More detail on the so-called 'gigabit' film which
seems to promise large-format quality from 35mm negs (well, more or less
anyhow). I really like the warning about 'psychological consequences' of
using the film if you are over 25 years old!

> [added rec.photo.film+labs to the discussion as they might be interested
> in this as well and i'm not gonna type this twice  ;]
> 
> Peter De Smidt <pdesmidt@fdldotnet.com> wrote:
> 
>>> have a look at www.gigabitfilm.de. Their page is still in
>>> German only, however the test films they are shipping are coming out
>>> quite well. Beats TP at resolution.
>>> 
>> Do you know any more about the film?  For example, what's it's spectral
>> response (extended red, eg) ? Inherent contrast?
> 
> the short answer: spectral response is pan with slightly less red
> sensibility than average b/w films...  contrast depends [obviously] on
> development but should be "normal" with their special gigabitfilm
> developer
> 
>> My German is too rusty to tell much.
> 
> well, my english is not top either, but here's a rough translation:
> 
> -------------
> 
> Provisional data sheet for KB film 40 ISO, status 16.7.2000
> 
> Only valid in connection with Gigabitfilm chemistry for provisional KB
> film ISO 40 of the test phase Gigabitfilm GmbH, H. Boell STR 17, 52372
> Kreuzau, fax: 02422/500460
> 
> 
> Film-type: Silverhalogenid Film
> 
> Carrier: Polyester (PET=Polyethylenterephtalat), can be cut only with
> scissors.
> 
> sensibility: panchromatic, slightly lower red-sensibility than usual
> panchromatic films.
> 
> Dissolution: 720 linepairs/mm at contrast 1:1000
> 
> Grain: very low, in high density areas low
> 
> Processing: in cleaned tanks, must not contain traces of wetting agents
> 
> Develop:
> use 250 ccm of working solution (1+9) per roll 135/36, for first tests
> develop for 6 min at 20°C for a gamma of 0.5-0.6 (gradations-/
> temperature- [up to 26°C]/time curves follow, emulsion load must still
> be measured), agitations interval of 20 sec.
> The Gigabitfilm chemistry is free from any creation of cloudy stains and
> artifact, even with insufficient agitation. Some users however
> encountered occasionally problems, but problems with the processing
> equipment are suspected there.
> Chemistry is intended for use in 250 ml doses. For normal processing in
> inversion tanks, the usual air over the fluid level of the filled tank
> inclusive spiral with film is sufficient. This air volume should consist
> of approx. 60 to max. 100 ml.
> 
> the current gigabitfilm developer is not suited for rotary processing.
> 
> [snip]
> 
> Stop: water rinse (ca. 5 sec.)
> 
> Fix:
> common rapid-fixers, approx. 10-20 sec (yes, ten to twenty seconds,
> gigabit films have much smaller silver grains than usual films)
> over fixing (more than 2-3 minutes) can affect the shadow detail
> density.  feel free to check for clearing time, fixing time is three
> time the clearing time as usual.
> 
> Wash:
> normal processing: 30 sec to 2 min
> archival processing: minimum 5 minutes, details to come..
> 
> Dry:
> final rinse in distilled water recommended or spray distilled water on
> the hanging film.
> 
> Attention:
> the film will look very thin while dry, the final density will appear
> when dry:
> 
> Printing:
> The thin emulsion and a special anti-dust coating makes printing easy.
> 
> Enlarger and lenses:
> Remove at least the lower glass carrier, otherwise MTF loss will occur,
> good glass less carriers are recommended. don't stop down below f5.6
> 
> Taking lenses:
> the quality of taking lenses is a very hot topic if used with
> gigabitfilm.  Avoid stopping down below f5.6.  Many lenses are built to
> increase contrast which might reduce resolution considerably. Some
> lenses can archive a resolution of 350lp/mm in the final print.  [1]
> 
> [snip]
> 
> Film transport:
> sometimes camera with automatic rewind it can happen that the camera
> starts to rewind the film after 24-30 exposures. This could be because
> of the PET carrier, the advantages of this carrier make up for this
> flaw, but later confection in 136/24 is intended.
> 
> Flash shots:
> Please process 10% longer!
> 
> Cameras with TTL- and Flash metering:
> If using cameras with TTL metering, the brighter emulsion more light
> than common film material. This has to be taken into account as this can
> make a difference up to 2 f-stops. [2]
> 
> [snip]
> 
> Unknown risks:
> Please report back so that others don't have to make the same mistakes.
> 
> psychologic risks:
> studys show that test users over 25 years will have to face the
> following dilemma after one week gigabitfilm testing [3]: their whole
> lifetimes work, their whole archive looks worthless compared to the
> quality of gigabit film. In those cases unusual psycholocic reactions
> may occur such as active forgetting or head ache. this note may be an
> advise to users over 25 to test gigabitfilm carefully and slowly, but
> consequently.  additionally one is only as old as one feels.
> 
> 
> ---------------
> 
> 
> doh, that was quite some work...   note that i snipped some parts which
> were cumbersome and i didn't consider to be worthwhile  ;] ... also note
> that i never used gigabitfilm [but i probably will] and therefore can't
> comment on their information...
> 
> hope that helped,
> ++ christoph ++
> 
> 
> 
> 
> notes from the translator:
> 
> [1] didn't we have a thread recently that high quality taking lenses
> will not resolve significantly more than 150lp/mm?
> 
> [2] this reads as (2Pi) f-stops in the original (even the html code)
> which is probably a typo...  2 stops sound like an awful lot to me
> though, so maybe this could also be 2/3 stop or something
> 
> [3] i know that this part doesn't make a lot of sense in the
> translation, but it's also rather odd in the original [as is a lot of
> the rest of the text ;] - so i did my best...  actually this whole
> paragraph is a lot of nonsense to me - they must be nuts to think that
> my whole lifetimes work is about grain and resolution...  oh well, but
> then i'm only 24 too  ;]
> 
> 
> the usual disclaimer apply like:
> I have no connection to the mentioned company  blah bla...  data may be
> incorrect blah bla...  translation may be incorrect blah bla... etc
> etc..  use at your own risk etc etc  ...  ;]
- -- 
John Brownlow

http://www.pinkheadedbug.com