US3623418A - Photographic developer replenishment - Google Patents

Photographic developer replenishment Download PDF

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Publication number
US3623418A
US3623418A US848867A US3623418DA US3623418A US 3623418 A US3623418 A US 3623418A US 848867 A US848867 A US 848867A US 3623418D A US3623418D A US 3623418DA US 3623418 A US3623418 A US 3623418A
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developer
test strip
replenisher
bath
density
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US848867A
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Clarence S Ost
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03D—APPARATUS FOR PROCESSING EXPOSED PHOTOGRAPHIC MATERIALS; ACCESSORIES THEREFOR
    • G03D3/00—Liquid processing apparatus involving immersion; Washing apparatus involving immersion
    • G03D3/02—Details of liquid circulation
    • G03D3/06—Liquid supply; Liquid circulation outside tanks
    • G03D3/065—Liquid supply; Liquid circulation outside tanks replenishment or recovery apparatus
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N21/86—Investigating moving sheets

Definitions

  • Developer replenisher is added to a bath of photographic developer, in accordance with monitoring of a test strip of photographic material developed by developer sampled from the bath, for the purpose of compensating for any loss in activity that otherwise would occur because of use, aging, or other reason.
  • the photosensitive test strip is transported successively through an exposure chamber wherein it is exposed to actinic light, a development chamber wherein the exposed strip is developed by the sample of developer, and finally a monitoring chamber wherein the developed optical density of the strip determines the amount of light passing from a non-actinic light source to a photoresistive element in an electronic system for controlling the addition of replenisher to the developer bath.
  • the monitored density is checked continuously against a value corresponding to an acceptable plateau of developer activity, and also periodically for any decrease in density as compared with the results obtained when last previously checked, and if deficient is adjusted upward by intermittent addition of replenisher in accordance with the prevailing rate of decrease in density.
  • This invention relates to replenishment of photographic developer to maintain the activity thereof, as in a bath of developer wherein development is taking place and is thereby depleting the activity of the developer.
  • a primary object of the present invention is improved sampling of photographic developer for monitoring of the activity thereof.
  • Another object is improved monitoring of the activity of sampled photographic developer for determination of changes therein and of the desirability of adding developer replenisher.
  • a further object is improved addition of developer replenisher to photographic developer in accordance with monitoring of developer activity and changes therein.
  • Yet another object is provision of apparatus for performing the foregoing process steps automatically.
  • FIG. 1 is a view in side elevation, partly schematic, of apparatus components of this invention, especially in relation to a test strip of photographic material;
  • FIG. 2 is a like View of another embodiment of components relative to a test strip
  • FIG. 3 is a view in enlarged side sectional elevation of one of the apparatus components of the preceding iviews, specifically a block comprising an exposure chamber;
  • FIG. 4 is a perspective view of components of the apparatus of FIG. 3;
  • FIG. 5 is a plan view of lm exposed in the apparatus of the immediately preceding views
  • FI-G. 6 is a like view of film exposed in somewhat modied manner
  • FIG. 7 is a view in enlarged side sectional elevation of another component of FIGS. l and 2, specifically a block comprising a development chamber and a monitoring chamber;
  • FIG. 8 is a largely diagrammatic view of developercontaining means and related items'.
  • FIG. 9 is a schematic showing of electrical apparatus useful according to the invention.
  • the -objects of the present invention are accomplished by exposing a test strip of photographic material, extracting from a bath of developer in which subject photographic material is being developed a sample of such developer, developing the exposed test strip with the sample of developer, sensing optical density of the developed strip, and adding developer replenisher from a source thereof to the developer bath in accordance therewith.
  • FIG. 1 shows test strip 10 of photographic material stored in unexposed form on supply reel 11 shown fragmentarily at the left, from which it unwinds over roller 12, between exposure block 13 and pressure pad 14, then between development and monitoring block 23 and pressure pad 24, through the nip of drive roll 27 and idler roll 28, and onto takeup roll 31 shown fragmentarily at the right.
  • the respective pressure pads are resiliently supported on leaf springs 15 and 25, the opposite end thereof being secured by respective brackets 15a and 25a to a supporting frame (indicated only diagrammatically).
  • Idler roll 28 is pivotally supported on swing arm 26, the other end of which is pinned to the frame, and is biased toward drive roll 28 by extension spring 29 attached to an intermediate part of the arm.
  • the drive roll is rotated by synchronous strip transport motor 30 to forward the test strip onto takeup reel 31.
  • Electrical power is supplied by a pair of leads from external connection points x, y to the motor, to the exposure block via constamt-voltage device 9 and to the development and monitoring block via constant-voltage device 19.
  • the latter block has respective developer sample inlet and outlet tubes 33 and 34 extending from its base, and its pressure pad 24 has pair of electrical leads 37 and 38 extending therefrom to ground and to external point a, respectively.
  • FIG. 2 contains essentially everything shown in FIG. l plus certain additional items interposed between exposure block 13 and development and monitoring block 23.
  • Added synchronous strip transport motor 50 rotates drive roll 47, toward which idler roll 48 on swing arm 46 is biased by extension spring 49 to form a nip to receive and forward test strip 10 of photographic material.
  • the test strip then passes under idler roll 52 carried on swing arm 56, which is biased by extension spring 59 away from a straight-line path, and over idler roll 58 mounted on a fixed axis in the straight-line path.
  • actuating arm 61 of limit switch 62 which has switch arm 63 in one side of the power line such that the switch is opened when there is enough Slack in the test strip to permit an extreme downward swing of the arm and such that the switch is closed when there is such a minimum of slack in the test strip to raise the arm to an extreme upward position.
  • Synchronous strip transport motor 30 in the vicinity of takeup reel 31 is not connected to the external power line connections in this embodiment but is connected to points 1', i identified further hereinafter.
  • FIG. 3 shows, exposure block 13 enlarged and sectioned to reveal the interior chamber, which is in the form of a cylindrical bore with lamp 16 in the lower end thereof and with umbra-penumbra slits 17, 18 intervening between the lamp and the overlying test strip, as shown further (in perspective) without the exposure block itself in FIG. 4.
  • Pressure pad 14 is shown in phantom in its alternative lifted position (with leaf spring 15 flexed) which facilitates introduction of the test strip to cover the open upper end of the chamber bore.
  • FIGS. and 6 show developed test strip portions 10 and respectively, with developed variable-density characteristics corresponding to varying exposures along the strip length.
  • the variable-width clear track flanked by an opaque background, as shown in FIG. 5, results from application of a hard (high contrast) litho type of developer to a strip exposed with the slit geometry of FIGS. 3 and 4.
  • a homogeneous varying density characteristic, as shown in FIG. 6, will result from exposure through a single plain slit similar to 17 located close to the lamp, upon development with a soft (low contrast) developer. IEither of the above or other techniques may be used satisfactorily in the practice of this invention.
  • FIG. 7 shows development and monitoring block 23 enlarged and sectioned to show the interior chambers formed by left and right vertical bores 71 and 81 therethrough and overlain by pressure pad 24, which is also shown (in phantom) in its alternative lifted position with supporting leaf spring 25 ilexed accordingly.
  • Left bore 71 receives sample inlet tube '33 and sample outlet tube 34 in watertight contact at its bottom end.
  • the inlet tube terminates in communication with the bore at that end, but the outlet tube continues upward toward the top end and terminates in communication with central opening 73 in spacer 70, which defines development space 74 at the top of the bore.
  • the spacer has pair of gaps 72, through which developer passes into the development space, from which it exits through the central opening in the spacer, as indicated by arrows.
  • the monitoring chamber through which the test strip passes next is composed of bore 81 in block 23 and bore 82 in pressure pad 24.
  • Lamp 83 removably retained by seat 87 in the upper part of bore 81 has electrical leads extending thereform and out the bottom of the block to constant-voltage device 19.
  • Filter 85 in the top end of bore 81, between lamp 83 and test strip 10 (now developed and coated with developer) renders the light transmitted thereby non-actinic to avoid further exposure (and development) of the test strip.
  • densitometer head 84 Located in overlying bore 82 and juxtaposed to the opposite side of the ⁇ test strip from lamp '83 is densitometer head 84, whose electrical photoresistance (R4, not separately shown) varies in accordance with the intensity of light incident 'thereon as transmitted through the developed test strip and whose electrical leads connect to ground and to point a, respectively, as shown in FIGS. 1 and 2.
  • FIG. 8 shows bath 92 of developer in developing tank 91, in which subject photographic material supported by belt 90 is being developed as it is transported about sets of rollers, including drive roller 93.
  • Pipe ⁇ 94 leads from lthe bottom of the tank past a junction with ⁇ tube 34, which is the sample outlet tube from the test development charnber in monitoring block 13.
  • Pump P is present in the pipe between that junction and a junction with tube 33, which is the sample inlet tube to the test development chamber, to produce the desired circulation (indicated by arrows).
  • pipe ⁇ 94 Before discharging into the top of development tank ⁇ 91, pipe ⁇ 94 is constricted into venturi ⁇ 95, to which replenisher tube 96 is connected. The other end of tube 96 is immersed in supply of developer replenisher 97 in container ⁇ 98.
  • the tube is enlarged into flow chamber 99.
  • the interior of the flow chamber is so constructed that opening of valve 103 electrically by solenoid 104 will enable replenisher to flow, at a rate indicated by flowmeter 100 and controllable by manual setting of knob 102 to series valve 101, from container 98 through tube 96 and into pipe 94 to tank 91, where it mixes with bath 92 developer therein to raise the activity thereof.
  • the pump is driven by motor M connected to external power points x, y and provided with manually actuatable speed-control means having control dial 105.
  • motor M also turns drive roll y93, so as to transport subject photographic material supported by belt through developer bath ⁇ 92, and rotates electrical alternator G, which connects to points i, i also shown in FIG. 2 as connecting to the leads for synchronous strip transport motor 30 for which the alternator furnishes electrical power in that embodiment.
  • the solenoid coil connects to external power point y and to control point c, which is identified further in the description of the next View.
  • FIG. 9 shows electrical control apparatus of this invention, largely schematically and partly in block form.
  • Control point c previously shown in FIG. 8, is at the right alongside external power point x.
  • comparison means including a resistance bridge.
  • the bridge is composed of fixed resistors R1 and R3 in the upper left and right arms, respectively, adjustable resistor R2 in the lower left arm, and photo-variable resistance R4 (not shown) of dcnsitometer head 84 in the lower right arm as indicated by the lead to point a (also shown in FIGS. 1 and 2). Electrical potential is supplied across the bridge from bottom (positive) to top (negative) by battery B1, and activity meter AM is connected transversely across the bridge as an indicator of bridge balance when centered.
  • trigger circuits 1 and 2 Shown in block form at the lower right of FIG. 9 ⁇ are trigger circuits 1 and 2, both of which are wholly conventional and, therefore, not further illustrated or described except for input and output elements thereof. These circuits have respective input transistors, T1 and T2. The base of transistor T 2 at the right is connected to receive the bridge output from a terminal at the left side of the bridge (slider of R2). Each such circuit also has an output relay: RL1 for trigger circuit 1, and RLZ for trigger circuit 2.
  • Relay RL1 actuates double-throw switch S1, which has arms A1, A2, and A3, and relay RLZ actuates single-throw switch S2, which has only arm A. Both switches are shown with their arms in the normal rest position occupied thereby 4when not actuated by the relays.
  • the respective switch arms connect as follows: A1 to capacitor C1, which in turn connects to the left or output side of the bridge; A2 to C2, the other side of which is grounded, and to R6, which goes to the negative terminal of battery B2, the positive terminal of which is grounded; A3 to connection point c (see also FIG. 8); and A to external power point x.
  • the contacts that are closed in the indicated rest position of the switch arms are themselves connected as follows: A1 to one side of diode D, the other side of which is grounded; A2 to the normally closed contact for arm A2 and to resistor R5; which connects to the base of transistor T1; A3 (and A) no contact.
  • the normally open contacts for the respective arms are themselves connected as follows: A1 to the normally colsed contact for arm A2 and to resistor R5; A2 to the positive terminal of battery B3, the negative terminal of which is grounded; A3 and A to one another.
  • Test strip 10 of photographic material is unwound from supply reel 11 and is transported, whether according to the FIG. 1 embodiment or the FIG. 2 embodiment (which are distinguished subsequently hereinafter) past exposure block 13 and there exposed bylamp 16, then past test development chamber 71 of development and monitoring block 23, where it is ooded With developer sampled from bath 92 thereof (in tank 91) in ⁇ which subject photographic material is being developed.
  • the developed test strip passes between lamp 83 and densitometer head 84, which senses the intensity of light transmitted through the strip as an index of the optical density thereof, before being wound up onto takeup reel 31.
  • the sampling of developer for development of the test strip is continuous, with return of the continual ow of samples back from test development chamber 71 into bath 92.
  • the electrical resistance (R4) of the densitometer head 84 will be so high (because of diminution in transmitted light) that the bridge will be in balance or be slightly unbalanced to the right, and will be so shown on activity meter AM, indicating adequate activity.
  • the output potential at the lead from the left side of the bridge to the base of input transistor T2 of trigger circuit 2 is either positive, zero, or insufliciently negative to cause transistor T2 to conduct and actuate relay RL2, and such closed gate condition precludes addition of developer replenisher, as will become further apparent from the description below.
  • the amount of replenisher added depends upon the period during which both relays RL1 and RLZ are closed. As previously mentioned, if the bridge output to the base of transistor T2 goes positive, indicating that a preselected activity plateau has been reached, transistor T2 will cease conducting and relay RLZ will drop out, thereby interrupting the power to the valve solenoid and discontinuing addition of replenisher regardless of conduction by transistor T1. However, so long as the sensed developer activity is less than such -plateau value, replenisher addition will be simultaneous with conduction in transistor T1.
  • Switch S1 is thrown periodically by relay RL1 whenever the base of transistor T1 becomes negative so that the transistor conducts.
  • the switching repetition rate 1s largely controlled by the time constant of capacitor C2 and resistor R6.
  • arm A2 connects capacitor C2 directly across battery B3, which charges its upper plate positive.
  • arm A2 disconnects capacitor ⁇ C2 therefrom and connects it through resistor R6 across battery B2, which has opposite polarity, and the positive charge leaks off the capacitor until the base of transistor T1 becomes slightly negative again, whereupon the cycle repeats.
  • the net change in the bridge C1 output over one switching repetition period is proportional to the average rate of change of density in the developed test strip and, thus, to the average rate of change of sampled developer activity.
  • the addition period (and, thus, total) of replenisher added at any sample period is likewise proportional to the rate of change in developer activity, rather than to amount of change in activity. Accordingly, whenever the rate of depletion in developer activity increases (or decreases), the control system of this invention responds promptly thereto with'the net result of compensating therefor.
  • manual ow control valve 101 is set so that the ilow occurring when solenoid 104 opens valve 103 is somewhat higher than would produce a total flow of replenisher exactly suiiicient to compensate for the actual decrease in activity level since the last previous sampling. This is highly desirable, in large part because of time lag inherent in developer circulation and the test development period.
  • the net effect of practicing the process of the invention is to prevent wide swings in developer activity by sensing depletion in activity promptly and proportioning addition of replenisher in accordance with the rate of depletion and, on the other hand, eliminating such addition whenever the sensed activity reaches a preselected activity plateau.
  • test strip may be transported according to either the relatively simple arrangement shown in FIG. l or the somewhat more complex system shown in FIG. 2, whichever better meets the needs of the user.
  • the entire path of the test strip, a least unil it is ready to be wound onto takeup reel 31, is shielded from external light so as to avoid interfering with the testing steps of the process.
  • test strip 10 is transported at essentially constant speed through development chamber 71 (as well as the previous exposure chamber and subsequent densitometric chamber) so that its period of development bears no particular relationship to the period of development of subject photographic material supported by belt 90, which normally is a function of the speed of motor M as set on speed-control dial 105 (as well as of the total path length from entry to exit from developer bath 92).
  • the transport arrangement of FIG. 2 can be substituted, wherein the test strip is pulled at essentially constant speed past the exposure block by added synchronous motor 50, but provision is made for storing excess exposed iilm if such initial rate of transport somewhat exceeds the subsequent rate of transport thereof through the development and monitoring chamber and for interrupting the exposing and initial transport of the test strip if such initial rate of transport greatly exceeds the subsequent rate.
  • swing arm S6 takes up the slack in the test strip until the amount of slack taken up is sufcient to lower the swing arm enough to open limit switch 63, thereby interrupting the electrical circuit to both exposure la-mp 16 and motor 50.
  • the exposed test strip is pulled by synchronous motor 30 past development and monitoring block 23 and is developed in development chamber 71 therein for a time proportional to the time of development of photographic material supported by belt 90 in developer bath 92 because synchronous motor 30 is not supplied with the same electrical power supplied to synchronous motor 50 but with power from alternator G instead (see connections i, i in FIG. 8).
  • the alternator is driven in turn by motor M, which also turns drive roll 93 to transport the subject photographic material through the developer bath.
  • motor M which also turns drive roll 93 to transport the subject photographic material through the developer bath.
  • this invention provides greatly improved apparatus and methods for sampling photographic developer so as to monitor the activity thereof, for monitoring such activity so as to determine changes therein and the desirability of adding developer replenisher to compensate therefor, for adding such replenisher to compensate for such changes, particularly in accordance with sensed rate of depletion therein without exceeding an acceptable preselected plateau of activity.
  • exposure block 13 may be combined with development and monitoring block 23 into a single block, with corresponding reduction in the number of springs and pressure pads, if desired.
  • Individual pressure pads may be used in place of combined pad 24 in any instance, and a coil spring may be used in place of a leaf spring, of course, or other biasing means may be substituted, as may other types of pads.
  • Other modifications may be suggested to persons ordinarily skilled in the art, in the light of the present disclosure. The invention itself is deiined in the following claims.
  • an improved developer replenishing process comprising extracting successive samples of developer from the bath, developing the exposed test strip with the samples of developer, sensing optical density of successive portions of the developed strip, comparing the density of the last sensed portion with the density of the last previously sensed portion, and adding developer replenisher from a source thereof to the developer bath only if the density of the last sensed portion is less than the density of the last previously sensed portion.
  • test strip is transported continuously at a xed rate through an exposure zone in which it is so exposed and a subsequent developing zone in which it is so developed.
  • test strip is transported discontinuously, but at a fixed rate of transport during the transporting thereof, through an exposure zone in which it is so exposed, and subsequently transporting it through a development zone at a rate of transport inversely proporitoned to the time of development of the subject photographic material.
  • A7 Developer replenishing process according to claim 6, wherein the developer replenisher is added at timed intervals and the rate of decrease is determined with respect to the last timed interval.
  • apparatus for developer replenishment including means for exposing a photosensitive test strip, means for developing such exposed test strip in developer from a bath thereof in which photographic material is developed, and means for sensing optical density of successive portions of the test strip; improved means for controlling addition of developer replenisher from a source thereof to the bath, comprising means for comparing the sensed density of a current portion and of a previous portion of the test strip, and means for adding replenisher in accordance with the results of such comparison, wherein the means for sensing optical density of the test strip includes an electrical bridge circuit, and the control means comprises an electrical switching circuit having first and second states with respect to conduction therein, timing means for converting from the first to the second of the states of the switching circuit and thereby periodically checking the sensed optical density, switch means responsive to the conduction states of the switching circuit and having a first position precluding addition of replenisher and a second position permitting addition of replenisher and corresponding respectively to the first and second states of the switching circuit, electrical charge storage means interposed between the bridge circuit output and the switching circuit for interonneting
  • apparatus for developer replenishment including means for exposing a photosensitive test strip, means for developing such exposed test strip in developer from a bath thereof in which photographic material is developed, and means for sensing optical density of successive portions ofthe test strip; improved means for controlling addition of developer replenisher from a source thereof to the bath, comprising means for comparing the sensed density of a current portion and of a previous portion of the test strip, and means for adding replenisher in accordance with the results of such comparison, wherein the control means includes means for precluding addition of developer replenisher whenever the sensed density of the current portion of the test strip is indicative of a preselected plateau of acceptable developer activity level.
  • Apparatus for developer replenishment includes an electrical bridge circuit
  • the control means includes an electrical switching circuit having rst and second states with respect to conduction therein, the first state being induced by bridge output oi at least a given value indicative of sensed density corresponding to the plateau of acceptable developer density and the second state being induced by bridge output of less than that given value, switch means responsive to the conduction states of the switching circuit and having a first position precluding addition of replenisher and a second position permitting addition of replenisher and corresponding respectively to the first and second states of the switching circuit.
  • Apparatus for controlling addition of developer replenisher to a bath of photographic developer subject to depletion in activity'with use comprising means for transporting a photosensitive test strip past an exposure location, then past a developing location, and finally past a density-monitoring location; means for extracting developer from the bath, forwarding it to the developing lo cation, and returning it to the bath; densitometric sensing means at the monitoring location, including an electrical resistor device whose electrical resistance varies in accordance with the intensity of light incident thereon; electrical comparison means including an electrical bridge circuit having that resistor device interconnected thereinto, electrical control means responsive to the bridge circuit output and electrically operated valve means for adding developer replenisher to the bath in accordance with operation of the control means; the control means comprising first and second switch lmeans having first and second positions each and both being interconnected to the electrically operated valve means to actuate such valve means when the switch means are in their respective second positions, rst and second control circuits for the respective first and second switch means, each of the control circuits
  • valve means is preadjustable for rate of ow of developer replenisher such that the amount of replenisher passing therethrough during a period of actuation of the valve is in excess of the amount that would be required to compensate for the sensed decrease in optical density.

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US848867A 1969-08-11 1969-08-11 Photographic developer replenishment Expired - Lifetime US3623418A (en)

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CA (1) CA934203A (enrdf_load_stackoverflow)
DE (1) DE2039718A1 (enrdf_load_stackoverflow)
FR (1) FR2056792A5 (enrdf_load_stackoverflow)
GB (1) GB1288464A (enrdf_load_stackoverflow)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3828172A (en) * 1973-06-04 1974-08-06 Eastman Kodak Co Replenishment controller for photographic processors
US4293211A (en) * 1980-07-14 1981-10-06 Pako Corporation Automatic replenisher control system
WO1986004522A1 (en) * 1985-02-01 1986-08-14 Kodak Limited Liquid chemical mixing method and apparatus
US4642276A (en) * 1984-10-04 1987-02-10 Agfa-Gevaert, N.V. Method of assessing the activity of a photographic developer
WO1988009528A1 (en) * 1987-05-29 1988-12-01 Kodak Limited Photometry
US4881095A (en) * 1987-09-11 1989-11-14 Fuji Photo Film Co., Ltd. Process for developing photographed film and for printing images through developed film
US4985320A (en) * 1989-05-31 1991-01-15 E. I. Du Pont De Nemours And Company Processor chemistry control strip reader and replenishment system
WO1992012414A1 (en) * 1990-12-27 1992-07-23 Eastman Kodak Company Web inspection system and method
US5408289A (en) * 1992-12-02 1995-04-18 Eastman Kodak Company Scanner for photographic processor

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2248314B (en) * 1990-07-31 1994-03-16 Ilford Ltd A photographic processing tank
US5561491A (en) * 1995-05-10 1996-10-01 Eastman Kodak Company Variable loop additive control for a photographic processor

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3828172A (en) * 1973-06-04 1974-08-06 Eastman Kodak Co Replenishment controller for photographic processors
US4293211A (en) * 1980-07-14 1981-10-06 Pako Corporation Automatic replenisher control system
DE3127822A1 (de) * 1980-07-14 1982-06-16 Pako Corp., 55440 Minneapolis, Minn. Automatisches nachfuellsteuersystem
US4642276A (en) * 1984-10-04 1987-02-10 Agfa-Gevaert, N.V. Method of assessing the activity of a photographic developer
WO1986004522A1 (en) * 1985-02-01 1986-08-14 Kodak Limited Liquid chemical mixing method and apparatus
WO1988009528A1 (en) * 1987-05-29 1988-12-01 Kodak Limited Photometry
US4881095A (en) * 1987-09-11 1989-11-14 Fuji Photo Film Co., Ltd. Process for developing photographed film and for printing images through developed film
US4985320A (en) * 1989-05-31 1991-01-15 E. I. Du Pont De Nemours And Company Processor chemistry control strip reader and replenishment system
WO1992012414A1 (en) * 1990-12-27 1992-07-23 Eastman Kodak Company Web inspection system and method
US5408289A (en) * 1992-12-02 1995-04-18 Eastman Kodak Company Scanner for photographic processor
EP0600383B1 (en) * 1992-12-02 1999-03-03 Eastman Kodak Company Scanner for photographic processor

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GB1288464A (enrdf_load_stackoverflow) 1972-09-13
FR2056792A5 (enrdf_load_stackoverflow) 1971-05-14
CA934203A (en) 1973-09-25
DE2039718A1 (de) 1971-02-25

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