ADVANCED TECHNOLOGYOPTICAL FLUID
IMAGING FROM FILM
The Naked Eye: PersonalViewReproductive ImagingWet DarkroomDigital ScanAll Three Imaging methods:Are subjectto and limited byoptic’s lawsAre subjecttotheimaging method’s capabilities andlimitation
Wet DarkroomTransfers data from onemediumto anotherLaborious processLow reproducibility even by same operatorOutput media dependentGood to poor fidelity to the originalSecond generation duplicates unlike original
Reproductive Imaging Methods Compared
Transfers data from one decaying medium to another decaying mediumLaborious processDifficult and laborious repetitive iteration or editingOriginal always neededLow fidelity of Second generation duplicates
Preserves data from one decaying medium to non-decaying numbers.Relatively Simple processEasy repetitive iteration or editing.Originalneeded the first time only.Identical second generation duplicates
Optical Limitations ofDRYImaging from Film
Light going through dry film is subject to some Scattering at the film grain. Consequences:Lower contrastEmphasized grainReduction in color saturationOver emphasis on scratches and dustReduced dynamic rangeLimitations shared by analog and digital methods but can be overcome for both.
DRY Imaging from FilmPHYSICALlimitations
Film CurvatureCorrection requires glass: negative consequences:Additional refraction, -Loss of sharpness and contrastUse of Anti Newton Glass: Loss of sharpness and contrast.
OpticalAdvantages ofFLUIDImaging from Film
Elimination ofair / filminterphaseElimination ofLightscattering at grain =Higher contrastGreater sharpnessHigher fidelity rendition of grainHigher color saturationDust and scratch-reduction or eliminationRich gradation
PHYSICAL Advantages ofFLUID Imaging from Film
Film Flatness = Uniform plane of focusGlassneededonlyononesideGlass can be placed in non-refractivepositionOn side of light relativeto film’semulsionAvoids Anti Newton Glass
The Ideal Imaging Fluid
Causes no physical damage to Film or equipmentNot a solvent: Does not dissolve film backing or emulsion or drums, if drum scanned.Chemically inert under use or storage conditionsTry theScanScienceCup Test.OdourlessOperator Safe:Low Vapour toxicity:Free of Carcinogens, or target-organ toxics,Free of aromatic Hydrocarbons, Olefins and n-HexaneNot flammable under normal use conditionsHigh Flash PointNon toxic ?No such thing, all hydrocarbons are toxic by ingestion
Imaging Fluids:Special Concerns with Legacy Film
Many Film variantsNitrocellulose > Other cellulose backed films containingaromatic plasticizer: Tri-Phenyl Phosphate(TPP)Fluids containing aromatic hydrocarbons can extract the TPP : cause dimensionalchanges to film,increase brittlenessTry ScanScienceCup Test: tests solvent aggressiveness of fluid against Polystyrene apolyaromaticpolymer.Fluids that damage polystyrene can also extract TPP and may damage scanner drums
Developers of the Drum Scanner run Into Newton,Rings,they knewthose could be eliminated by fluid mounting.Theseguystried babyoil,and it worked.Thefirst generation imaging fluid was born!
Results were great...
But the drudgery had begun.As It turned out,baby'sbottomswere better with oil, not drums.Cleaning the drum required nasty, volatile and smelly stuff.If it were possible to eliminate the cleaning that would be great!There had to be a better way. A Better way?
A better way? Really?
Why not use the smelly volatile stuff used for cleaning the scanning oil as thescanning fluid.....Voila,it evaporated after use no cleaning needed!TheSecond Generationimaging fluidwas born!The cleaner, now the scanning fluid: the smellwas thesame, bad.Ah! but a great time saver. That was real progress.With the second generation scanning fluids Baby Oil went back to being babyoilandThe cleaning drudgery was gone.
All That Happened In....THE LAST CENTURY
Not bad for empirical DIY.
Primary on Newton
Light that strikes two reflective surfaces in close proximity and a slight angle to each other yields two wave fronts which reinforceeachother when in phase ordestruct when outof phase.The result is a series oflighterordarker rings.If the reflective surfaces are kept parallel, the resulting wave fronts areboth inphase:therefore, NoNewton rings!But, glass, if used to flatten film is a refractive element that degrades the image.A trade off.
Avoiding Newton RingsA better way
Filling the air space between the two reflective surfaces with a fluid:Forces the film into a flat planeEliminatesthe air space between reflectivesurfaces, makes the surfaces paralleland banishes Newton Rings.Withoutfluid scanning, drum scanners could have not become a commercial reality.The same technology is available to all scanners
Oil-type Imaging FluidsPros
THE PRO’SScanningOilsare practically Chemically inert to film and scanner drums.TheOilshigh molecular contributes to their low volatility and solvency.Oils have no tendency to flash off at the edges of the fluid mount.
PRO’S CONTINUEDScanningOilsare stable in storage because they are devoid of the reactive and smelly components natural to less pure petroleum hydrocarbonsTheOilslow volatilitymeansno vapours releasedOils are essentiallynot flammable.Bigplus!TheOilshigh viscosity and low volatility help maintain a good temporary bond between the components of the fluid mount.No flash off.
First Generation Scanning Fluids
THE PROS, ...CONTINUEDThat was the good news!
Oil-type Imaging FluidsCONS
Like bad guests, they won't go away when the party is over and need to be forcefully expelled.Removing the oil requires dry wiping / dilution with other hydrocarbon solvents which are volatile, and potentially flammable.Cleaning solvents solvent power must be high enough to remove tape residues. The added solvency can be incompatible with the drum or the coatings of some scanner glass beds.
Scanning fluidsThe Second Generation
Main advantages: no clean up required.Self cleaning, evaporate quickly afterthe scan.Main disadvantage:High volatility = vapour build up,Highly flammable below the freezing point.Gasoline-like smell,Substances present: those normally contained in less refined, cheaper, petroleum distillates.Aromatic andolefinichydrocarbons
LUMINAThird GenerationTHECONVERGENCE OF CHEMISTRY AND PHYSICS
LUMINATheIdeal Imaging Fluid
A'Lens'. -not a solvent:will not damagefilmor equipment.Lumina is aninertopticalmediumEarth and Operator friendly:Good for your image and you.High purity and consistent quality
OdorlessDoesn't' t flash-off while scanningDries clean, leaves no residuesNOT flammable at Room TemperatureLow vapour toxicitySimilar Refractive index as film
Polystyrene foam is highly susceptible to attack by solvents, particularly those containingaromatic and cyclichydrocarbons. As a rule, these substances have greater solvency.The cup at the center is a new cup. The cup at the left contained LUMINA for 24 hours. The cup at the right containeda second generation scannerfluid during 24 hours.Try the test yourself before trusting your film or scanner to an imaging fluid.
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