OPTICAL SCANNING FLUID
|IMAGING FROM FILM
The Naked Eye: Personal View
All Three Imaging methods:
Are subject to and limited by optic’s laws
Are subject to the imaging method’s capabilities and limitation
|REPRODUCTIVE IMAGING Wet Darkroom
Transfers data from one medium to another
Low reproducibility even by same operator
Output media dependent
Good to poor fidelity to the original
Second generation duplicates unlike original
|Reproductive Imaging Methods Compared
Transfers data from one decaying medium to another decaying medium
Difficult and laborious repetitive iteration or editing
Original always needed
Low fidelity of Second generation duplicates
Preserves data from one decaying medium to non-decaying numbers.
Relatively Simple process
Easy repetitive iteration or editing.
Original needed the first time only.
Identical second generation duplicates
|Optical Limitations of DRY Imaging from Film
Light going through dry film is subject to some Scattering at the film grain. Consequences:
Reduction in color saturation
Over emphasis on scratches and dust
Reduced dynamic range
Limitations shared by analog and digital methods but can be overcome for both.
Correction requires glass: negative consequences:
Additional refraction, -Loss of sharpness and contrast
Use of Anti Newton Glass: Loss of sharpness and contrast.
|Optical Advantages of FLUID Imaging from Film
Elimination of air / film interphase
Elimination of Light scattering at grain =
Higher fidelity rendition of grain
Higher color saturation
Dust and scratch-reduction or elimination
|PHYSICAL Advantages of FLUID Imaging from Film
Film Flatness = Uniform plane of focus
Glass needed only on one side
Glass can be placed in non-refractive position
On side of light relative to film’s emulsion
Avoids Anti Newton Glass
|The Ideal Imaging Fluid
Causes no physical damage to Film or equipment
Not a solvent: Does not dissolve film backing or emulsion or drums, if drum scanned.
Chemically inert under use or storage conditions
Try the ScanScience Cup Test.
Low Vapour toxicity:
Free of Carcinogens, or target-organ toxics,
Free of aromatic Hydrocarbons, Olefins and n-Hexane
Not flammable under normal use conditions
High Flash Point
No such thing, all hydrocarbons are toxic by ingestion
|Imaging Fluids: Special Concerns with Legacy Film
Many Film variants
Nitrocellulose > Other cellulose backed films containing aromatic plasticizer: Tri-Phenyl Phosphate (TPP)
Fluids containing aromatic hydrocarbons can extract the TPP : cause dimensional changes
to film, increase brittleness.
Try ScanScience Cup Test: tests solvent aggressiveness of fluid against Polystyrene a polyaromatic polymer.
Fluids that damage polystyrene can also extract TPP and may damage scanner drum
|IMAGING FLUIDS EVOLUTION
Developers of the Drum Scanner run Into Newton Rings, they knew those could be eliminated by fluid mounting.
These guys tried baby oil, and it worked.
The first generation imaging fluid was born!
|Results were great...
But the drudgery had begun.
As It turned out, baby's bottoms were 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 the scanning fluid.....
Voila, it evaporated after use no cleaning needed!
The Second Generation imaging fluid was born!
The cleaner, now the scanning fluid: the smell was the same, bad.
Ah! but a great time saver. That was real progress.
With the second generation scanning fluids Baby Oil went back to being baby oil and
The 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 reinforce each other when in phase or destruct when out of phase.
each other when in phase or destruct when out of phase.
The result is a series of lighter or darker rings.
If the reflective surfaces are kept parallel, the resulting wave fronts are both in phase: therefore, No Newton rings!
But glass, if used to flatten film is a refractive element that degrades the image. A trade off.
Avoiding Newton Rings A better way
Filling the air space between the two reflective surfaces with a fluid:
Forces the film into a flat plane
Eliminates the air space between reflective surfaces, makes the surfaces parallel and banishes Newton Rings.
Without fluid scanning, drum scanners could have not become a commercial reality.
The same technology is available to all scanners
|Oil-type Imaging Fluids Pros
Scanning Oils are practically Chemically inert to film and scanner drums.
The Oils high molecular contributes to their low volatility and solvency.
Oils have no tendency to flash off at the edges of the fluid mount.
Oil-type Imaging Fluids
Scanning Oils are stable in storage because they are devoid of the reactive and smelly
components natural to less pure petroleum hydrocarbons
The Oils low volatility means no vapours released
Oils are essentially not flammable. Big plus!
The Oils high viscosity and low volatility help maintain a good temporary bond between the
the components of the fluid mount. No flash off.
|First Generation Scanning Fluids
That was the good news!
|Oil-type Imaging Fluids CONS
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 fluids The Second Generation
Main advantages: no clean up required.
Self cleaning, evaporate quickly after the scan.
High volatility = vapour build up,
Highly flammable below the freezing point.
Substances present: those normally contained in less refined, cheaper, petroleum distillates.
Aromatic and olefinic hydrocarbons
|NEW TECHNOLOGY LUMINA Third Generation
THE CONVERGENCE OF CHEMISTRY AND PHYSICS
|The Ideal Imaging Fluid
A 'Lens'. -not a solvent: will not damage film or equipment.
Lumina is an inert optical medium
Earth and Operator friendly: Good for your image and you.
High purity and consistent quality
Doesn't' t flash-off while scanning
Dries clean, leaves no residues
NOT flammable at Room Temperature
Low vapour toxicity
Similar Refractive index as film
The ScanScience Cup Test
Polystyrene foam is highly susceptible to attack by solvents, particularly those containing aromatic and cyclic hydrocarbons.
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 contained a second generation scanner fluid during 24 hours.
Try the test yourself before trusting your film or scanner to an imaging fluid