From: Tony Conrad (email suppressed)
Date: Sun Jun 14 2009 - 10:51:41 PDT
OUTSTANDING and accurate, Jeffrey-------------
...I would only add that grey plastic and/or rem jet backings ALSO protect the
inner layers of a spool of film during daylight loading. This means that lab
stocks not protected in this way are far more transparent, and daylight loading
may expose all (or the greater portion) of your whole roll, even on a daylight
spool. I always load hi con and positive print stock in a changing bag.
----------------t0ny
On Sun 06/14/09 6:19 AM , JEFFREY PAULL email suppressed sent:
> Hi, Myron,
>
> YOUR FIRST QUESTION
> You are saying that the grey base of track neg. stock is not subject to
> chemical lightening.That grey look then is not simply a partial exposure. Was
that always the
> case even on older track neg stocks?
> Here's what I know, maybe some of this can fill in what you already
> know.
> The grey base of B&W neg stocks and I THINK, sound track stock, is in
> the plastic itself. Can't be washed or soaked out.Shooting B&W neg in a camera
means pointing it, sometimes, at scenes
> with immense intensity range,for example, streetlights at night. Some of that
blasty light hits the
> emulsion and continues through to the baseand also through the base itself to
its inner back side.
> Then it reflects back to the emulsion, but it's now spread out. So you get
> the glow around the streetlights.Even without dazzling lights, this bounce back
light can erase fine details
> sort of like a dirty lens can.So they dye the plastic grey to absorb at least
some of that stray
> light.Since neg is nver projected, they don't have to worry about diming the
> picture. (In using positive stocks they DO worry, so the base of positive
> stocks is clear.)The grey doesn't have to be very dark because that excess
light gets
> filtered twice: once hitting through the base to the back surface,and again as
it's reflected back through it to the emulsion.
> The grey base also prevents "light piping": When you are loading
> a 100' roll in a camera even in subdued light,some light will hit the edges of
the plastic and enter the base. Once the
> light's inside,it will stay inside, bouncing around as an "internal reflection".
> Optical fibres for communications exploit this internal reflection, but in
> movie film, it could cause edge fog beyond the run-off footage.So the grey
plastic base does double duty and absorbs this edge-fogging
> light as well.Filmstocks with Mylar/Estar plastic base are more prone to
light-piping
> than acetate base.
> Colour films (since early '60s) deal with halation in a different way.
> The plastic base of colour films is transparent, but a coating of carbon
> black is painted on the back side of the basewhen it's manufactured. This
layer, being opaque, is extremely efficient
> at absorbing this excess light.After exposure, it's served its purpose and has
to be removed to make the
> film transparent.The developing machines remove this coating as a 1st step in
development by
> scrubbing or blasting it off with water jets so none of the black particles
contaminate the next developing stages.
> The black layer is called a "rem-jet (removed by jets of water)
> layer".Kodak invented it and since they also invented the film and the developing
> processes, and had probably, at that time a 90% hold on the market,they could
use this coating and the make its removal a requirement of any
> development machines that would be manufactured.The B&W developing machines had
been in use for decades before the
> rem-jet method was invented,so to sustain compatability, it wasn't appled to
B%W films.
>
>
> SECOND QUESTION
> > Incidentally, what might the track sound like
> after some paint falls on it? instant avant garde sound composition....lol.
hmmmm. I think my next film
> may already be in the works here.....
> Myron, have you come acoss the animation of Norman Maclaren, yet?
> He and Len Lye in the '30s were the originators of scratching/painting on
> film.MacLaren was active at the National Film Board (Canada) from the '40s to
> the late '80s, I think.He made several films where his sound track was made
either by painting on
> transparent sound track, or scratching black sound track area, or actually
photographing
> strips of board with black lines on it, and then putting that image on the
> sound track. (No wonder he wound up sniffing glue.)
>
> If MacLaren is new to you,
> Check out: http://www.nfb.ca/explore-by/director/Norman-McLaren/
(Especially "Neighbours")
> and
> http://www.youtube.com/watch?v=E3-vsKwQ0Cg "Dots", which was made in 1940.
>
> There is also a long form doc on MacLaren's life and work.
>
> - Hope that you might find some of this interesting/helpful. (except maybe
> the glue part)
>
>
> One more week 'til the days start getting shorter and is still, around
> here, it goes up only to about 21C/70F.Nuts!
>
> JP
>
>
>
>
>
>
>
>
>
> >
> > In any case your point is well taken: that for
> printing or transfer >
> > the light can be adjusted
> accordingly.>
> > To my naked eye the dimming of this stock base
> does not look totally >
> > unusable for projection as well, maybe for
> certain instances. How bad >
> > could it be? Just a bit dimmer....
> >
> > Theoretically, not that it impacts the visual
> area of the frame, one >
> > could chemically remove the already exposed and
> process track area, >
> > at least for B&W. (eg. using the chemistry
> you mentioned in your >
> > earlier post).
> >
> > Color film track neg, of course, has the same
> orange backing as the >
> > regular color neg film stock, is it also dimmed
> down in the base? >
> > Hadn't ever noticed that.
> >
> >
> >
> > Myron
> >
> >
> >
> >
> >
> > On Jun 12, 2009, at 3:55 AM, JEFFREY PAULL
> wrote:>
> >
> >
> > > Hi, Myron,
> >
> > >
> >
> > > On Thu 11/06/09 16:22 , Myron Ort email suppressed
> > sent:
> > >> We talked of the chemistry doing this
> for b&w film,> but what will
> > >> remove opacity from a color print
> without removing the> emulsion?
> > >> Any info on this one?
> >
> > >>
> >
> > >> Unreel the film over the entire
> backyard or roof, and> let the sun
> > >> hit it all summer.
> >
> > >
> >
> > > No, actually, I don't know of anything,
> which explains> that
> > > particular silence in my text.
> >
> > >
> >
> > > - Jeffrey P.
> >
> > >
> >
> > >
> >
> > >
> >
> > > None of the following helps, but . .
> .>
> > > I remember there were chemicals you could
> use (or buy)> that
> > > lightened a colour film's individual dye
> layers to> colour-shift,
> > > or lighten underexposed slides. I think
> they turned the> colour dyes
> > > into their leuco variations which were
> colourless.>
> > > and if I remember correctly, this is what's
> happening> when dyes
> > > fade in the usual way.
> >
> > > These chemicals may have only worked on
> Kodachrome film> which has a
> > > different dye structure from all
> others.>
> > >
> >
> > > Until colour film really took over in the
> '60s,> photography had
> > > been enhanced by the ongoing labours of
> amateur> darkroom workers
> > > everywhere,
> >
> > > and hundreds of small companies making
> cheap> specialized gear and
> > > packaged chemicals.
> >
> > > These photo proto-nerds put tiny ads in,
> and published> their
> > > discoveries in the magazines of the era,
> and they knew> their
> > > chemistry and how to manipulate
> molecules.>
> > > Gone.
> >
> > > And now most of that photo infrastructure
> is gone, and> access to
> > > that information is also gone.
> >
> > >
> >
> > > Knowing that almost all film has been
> colour film for a> long time now,
> > > and that's just about all there is to begin
> a project> with, I'll
> > > keep cooking on it.
> >
> > >
> >
> > > A guy named Patrick Dignan published a lot
> of this sort> of stuff,
> > > see if Google helps give you
> leads.>
> > >
> >
> > > But probably the only feasable thing to do
> nowadays is> buy so-
> > > called "lightstruck"
> leader,>
> > > or B&W print stock - even from a lab
> that's still doing> B&W - and
> > > dunk it directly in photo fixer to remove
> the silver> halides
> > > and wind up with transparent film with
> gelatine coating> intact.
> > > B&W soundtrack stock works too, but it
> usually has a> grey plastic
> > > base which holds back some of the
> light.>
> > > This makes direct projection of original
> dimmer, but if> you're
> > > using it as original to be
> printed,>
> > > the lab can use a different light to
> compensate.>
> > >
> >
> > >
> >
> > >>
> >
> > >
> >
> > >
> >
> > >
> >
> __________________________________________________________________> > For info
on FrameWorks, contact Pip
> Chodorov at (address suppressed)> om>.
> > >
> >
> >
> >
> >
> >
> >
> __________________________________________________________________>
> > For info on FrameWorks, contact Pip Chodorov at
> (address suppressed)> om>.
> >
> >
> >
> >
> >
>
>
> __________________________________________________________________
> For info on FrameWorks, contact Pip Chodorov at om>.
>
>
>
>
__________________________________________________________________
For info on FrameWorks, contact Pip Chodorov at <email suppressed>.