Precautions In Drying
Precautions In Drying. Negatives Are Usually Dried By Standing Them In A Grooved Wooden, Metal, Or Ponce Lain Rack. Patterns Of These Have Bee Already Illustrated. A Porcelain Rack (fig 206) Is A Useful Acquisition, Taking Up Little Room And Being Also Available For Washing, By Standing It With The ...
Preparation Of Ferric Oxalate
Preparation Of Ferric Oxalate. Ferric Oxalate Is An Extremely Unstable Compound, And Difficult To Procure, So That The Experimenter May Have To Prepare It. In Any Case, It Must Be Tested From Time To Time By Taking A Small Quantity In A Test Tube And Adding A Few Drops Of ...
Preparation Of The Paper
Preparation Of The. Paper. The First Consideration Is The Choice Of A Suitable Paper, And For Experimental Work There Is Nothing Bettdr Than What Man's, Hot-pressed Drawing, Paper. Any Pure Paper May Be Employed, Avoiding Those With Glazed Surfaces And Those Which Appear To Be Sized With Impute Gelatine. Excellent ...
Preparations For Coating
Preparations For Coating. In Coating The Plate, The First Require Ment Is A Levelling Slab. The Best Form Consists Of A Glass Slab Of Patent Plate A (fig. 139), Resting On A Frame N, Supported By Three Levelling Screws C. This Can Be Ad Justed To A Nicety. And May ...
Preparing Gelatine Emulsion
Preparing Gelatine Emulsion. To Compound Such An Emulsion, Take 100 Grains Of Any Hard Pure Gelatine, Place It In A Jar Or Beaker, And Cover With Distilled Water. If The Sheet Gelatine Is Used, It Is More Convenient To Cut It Into Narrow Strips. After Allowing It To Stand For ...
Preparing The Bra Ssworh
Preparing The Bra Ssworh. The Machines Employed For This Are Of A More Or Less Familiar Description. The Breaking Away From The Traditions Of The Lens-making Industry, The Work Is Carried On As Far As Possible Upon The Inter Changeable System, All Dimensions And I Measurements Having Prescribed For Them ...
Preparing The Plate
Preparing The Plate. Sheets Of Plate-glass, From In. To -c; In. Thick, And Several Inches Larger Each Way Than The Required Picture, Are Necessary. These Must Be Ground With Fine Emery On One Side. A Simple Way Of Doing This Is To Place Two Plates To Gether, With Moistened Emery ...
Preservation Of Sensitised Paper
Preservation Of Sensitised Paper. Paper Sensitised In A Neutral Bath Is Extremely Liable To Deterioration By Dis Coloration, The Prints Produced By It, After Even About Two Days, Being Very Weak. To Avoid This Trouble, It Is Usual To " Fume " The Paper When More Than A Day Old, ...
Preservation Of The Paper
Preservation Of The Paper. Gelatine Is A Substance Somewhat Liable To Be Affected By Surrounding Conditions ; That Is To Say, It Is Liable To Decomposition If Stored In A Moist Atmosphere. This Danger Is. Increased If The Air Is Warm, As . Will Have Been Gathered From The Previous ...
Principle Of The Polariscope
Principle Of The Polariscope, The Polariscope Used With The Micro Scope Is In Two Parts ; The " Polariser " Mounted In A Sleeve To Slide Into The Tube Below The Stage Or Into The Substage (fig. 714), And The " Analyser " Mounted In A Tube To Fit Over ...
Printing
Printing. The Negative, With Its Back Carefully Cleaned, Is Now Laid, Film Up, In The Print Ing Frame, And The Packet Of Tissue Opened In Subdued Light. The Tissue Is Not So Sensitive As To Need To Be Kept In The Dark ; But Being More Sensitive Than Ordin Ary ...
Printing Appar Xtus
Printing Appar Xtus. As The Paper Cannot Be Examined During Printing, The Choice Of Frames, Broadly Speaking, Is Very Large ; In Fact, Any Kind Of Frame May Be Used. It Is Even Possible To Print A Bromide Without A Frame At All ; Merely Wetting The Paper And Squeegeeing ...
Printing On A Large
Printing On A Large Scale. The Routine Of Printing In A Large Estab Lishment Is As Follows. The Albumenised Paper Is First. Floated, And Then Hung Up To Dry In A Separate Room, The Floor Of Which Is Kept A Little Damp, Every Precaution Being Taken To Avoid Dust. Proof ...
Properties Of Colours
Properties Of Colours. As Already Indicated, Certain Colours Give An Impression Of Warmth, And Others Two Stars In Red And White Paper Respectively, And Fixing One Beside The Other On A Neutral Ground. As Indicated By Fig. 470. By Looking At The Red Star For A Few Minutes, Then At ...
Proportional Light Intensities
Proportional Light Intensities. It Will Be Admitted That Pictures Exist Only By Contrast ; Therefore, The Truest Im Pression Of Any Subject Can Be Imparted Only By A Thorough Study Of Its Contrasts In Tensities Which Have To Be Registered By The Photographic Plate ; And This Is Pro-' Bably ...
Proportionate Rendering Of Contrast
Proportionate Rendering Of Contrast. The Foregoing Experiment Will Show That The Contrasts Obtained With The Same Plate And Filter May Be Totally Different When The Exposure Is Unduly Prolonged. Among The Purposes For Which The Screen May Be Used, First And Foremost Comes That Of Toning Down Or Reducing The ...
Pyro And Ammonia Stock
Pyro. And Ammonia. Stock Solutions. No. 1.—liquor Ammonite, Sso° 1?, Oz. Potassium Bromide, ... S Drs. Water ... 2.—pyrogallic Acid ... 1 Oz. Citric Acid ... 2 Drs. Water ...... Or. • • • For Use, Take 1 Oz. Each Of No. 1 And No. 2, Separately, And Dilute With ...
Racks
Racks. These Also Are Dealt With In The Section On Development (p. 126), As Ell As In The First Section (p. 20). A Few Hints Will Be Example, " Pyro. Developer," " Ferrous Oxalate," And So On. This Should Be Done In Waterproof Varnish Or Paint, Of A Colour Which ...
Radium
Radium. Professor And Madame Curie Investi Gated The Residue From Pitchblende After The Uranium Had Been Extracted From It, And Found That It Was More Radio-active Than Uranium Itself. Eventually A Body Was Isolated From The Residue Which Was 300 Times More Active Than Uranium. This Was Named Potonitim. Another ...
Rapidity
Rapidity. Although This Subject Has Been Dealt With Elsewhere (p. 33), A Few Further Re Marks May Not Be Out Of Place. The Rapidity Of A Lens Depends Almost Entirely On Its Effective Aperture As Compared With Its Focal Length. The Measurement Of The Diaphragm Is Not Necessarily The Effective ...
Reasons For Varnishing
Reasons For Varnishing. The Reasons For Varnishing The Negative Are As Follows : (a) As A Protection Against Damp ; (b) As A Protection From Abrasions Of The Film, Or To Prevent The Retouching Being Disturbed ; (e) As A Support For Fur Ther Retouching. (a) If The Negative Is ...
Relation Of Binocular Vision
Relation Of Binocular Vision To Stereoscopy. Reference Being Made To Fig. S18, Let The Observer's Two Eyes Be Represented At N And It, And An Object Under Immediate Attention At A, To Which The Axes Of The Eyes Are Directed. Whilst A Is The Object Of Particular Attention, The Lenses ...
Reproduction Of Transmission Gratings
Reproduction Of Transmission Gratings. For Laboratory Work, Cheap Substitutes For The More Expensive Ruled Gratings Are Easily Obtained By Placing A Sensitised Plate In Contact With One Of The Glass Trans Mission Type. The Light Cannot Pass Through The Ruled Parts, So That, On Developing And Fixing, A Negative Of ...
Right Ascension And Declination
Right Ascension And Declination. If The Telescope Be Fixed At Right Angles To The Earth's Axis, Its Directional Line Will Trace In The Course Of One Rotation Of The Earth A Circle, Called The Celestial Equator, On The Imaginary Celestial Sphere. The First Point Of Aries, One Of The Equinoxes, ...
Roles For Flashlight Portraiture
Roles For Flashlight Portraiture. The Camera Should Generally Be About On A Level With The Chin Of The Model, And The Lamps Are Usually About 1 Ft. Above It And Slightly To One Side, So That The Light Falls At An Angle Of About 60'', And Is About 6 Ft. ...
Roughing Lenses
"roughing " Lenses. There Are Two Methods Of Shaping Glass, One Being To Heat It Till It Becomes Plastic, And The Other To Break Off Or Grind Away The Superfluous Parts Of A Rough Piece Un Til It Is Suitably Formed. Cheap Lenses Are Sometimes Made By The Former Method, ...
Routing
Routing. This Operation Consists Of Cutting Out Pieces Of Metal Or Making Hollows, Where The Block Is Required To Print White ; As In Catalogue Illustrations, Trimming Round Vignettes, Etc. This Is Done On A Small Scale With Chipping Tools, 'punches, And A Jig Or Fret-saw. In Large Firms, However, ...
Ruling Transmission Gratings
Ruling Transmission Gratings. The Grating Just Considered Is Termed A Transmission Grating. The Arrangement Of Alternate Transparent And Opaque Strips Is Obtained Most Easily By Ruling Fine Lines With A Good Diamond On Prepared Glass Surfaces. The Transmitting Portion Is The Unscratched Part, The Lines Made By The Diamond Diffusing ...
Sdertons Polarising System
Sderton's Polarising System. By Far The Best Method Of Stereoscopic Projection In Which Intermediate Aids Are Necessary Is That Clue To The Inventive Genius Of Mr. John Andertou, Of Birming Ham. One Of Two Slides, Prepared From Pictures Taken In The Stereoscopic Camera, Is Placed In One Lantern, And The ...
Selection And Arrangement
Selection And Arrangement. It Is A Mistake To Attempt To Include Too Much In The Picture ; A Small Portion Of A Landscape, Treated With Discrimina Tion And Taste, Will Be More Effective, As A Rule, Than A Wide Expanse Introducing Many Opposing And Conflicting Beauties. But The Arrangement Of ...
Selection Of Glass
Selection Of Glass. The Glass Of Which Lenses Are Made Is Purchased In The Form Of Rough Plates (sec Fig. 528) From -various British And Dustry, Suitable Machinery And Tools Can Not Be Purchased, As Looms For Weaving May Be. Opticians Have Either To Content Themselves With Relatively Crude Appli ...
Selection Of Lenses
Selection Of Lenses. The Selection Of The Lens Will Probably Give The Beginner More Trouble Than Any Other Part Of The Apparatus. Lenses Should Always Be Tested By An Expert Be Fore Purchasing ; Mere Examination Is Use Less. Some Methods Of Testing, Which Give However, The Hand Camera Will ...
Sensitising
Sensitising. The Sensitising Process Is Similar To That Described In The Paragraph " How To Sen Sitise," P. 170; But There Are Certain Ex Ceptions Which Should Be Mentioned. The Bath To Be Employed Should Be In A Neutral Condition, If Acid, It Will Give Poor Flat Prints.. The Strength ...
Sensitising Mixture
Sensitising Mixture. The Following Formula Is As Good As Any, But It Should Be Understood That Between The Multitude Of Formula Available There Is Very Little To Choose. White Sugar, 200 Grs. ; Gum ("rabic, 250 Grs. ; Ammonium Bichromate, 200 Grs. ; Methylated Spirit, 1 Oz ; Water, 20 ...
Sensitising The Metal
Sensitising The Metal. After Sufficient Washing, The Plate Is Allowed To Dry, Or Is Dried By A Gentle Heat If Wanted Quickly. If Intensified With Copper, It Will Require Varnishing First, Or The Copper Will Chemically Affect The Bichromated Film Used In Printing. Varnishing Is Done By Flowing A Weak ...
Sensitising The Plates
Sensitising The Plates. A Good Formula For Sensitising Is As Follows : Creutz Middle Hard Gelatine ... 1 Oz. Potassium Bichromate ... 50 Grs. Ammonium Bichromate ... 30 Grs. Chrome Alum ... „. 1 Gr. Water ... 10 Ozs. Water Is Divided Into Two Portions, The Gelatine Being In One ...
Sensitiveness Of Paper
Sensitiveness Of Paper. Bromide Paper Is Usually Made In Two Speeds, S'ow And Rapid. The Latter Is Number Of Different Papers, Which Give Almost Any Desired Contrast. 111:tnon Of Exposure. In Taking Up A Fresh Negative, A Test Should Be Made Either With A Strip Of Paper Or In Sections ...
Sharpening The Pencil
Sharpening The Pencil. The Next Thing Is To Sharpen The Pencil Pull Out About An Inch Of Lead, Lay Hat On The Sandpaper Block, And, Holding The Pencil Between Thumb And Forefinger, As In Fig. 229, Rub Backwards And Forwards, Pressing Very Lightly All The Time, Giving The Pencil A ...
Shredding And Washing
Shredding And Washing. Now This Potassium Nitrate, If Allowed To Remain, Would Practically Destroy The Sensitiveness Of The Emulsion, And Must. Therefore Be Removed. Fortunately, It Is Very Soluble. And May Be Easily Washed Out. An Hour's Washing Ill Distilled Water Is Ample To Remove Every Trace, And Even Less ...
Silver Chloride
Silver Chloride. When Metallic Silver Is Covered With Sufficient Nitric Acid, The Silver Will Be Dissolved, And On Evaporating This Solution, Flaky Transparent Crystals Will Result. This N Silver Nitrate, To Which Chemists Give The Formula It Being A Compound Of Silver (argentum), Nitro Gen, And Oxygen In The Proportions ...
Simplest Form Of Camera
Simplest Form Of Camera. A Photographic Image Is Formed On A Plate, Rendered Sensitive To The Action Of Light, By Throwing Upon It A Re Flection Of The Object Or Scene To Be Photographed. Those Parts Of The Plate Receiving The Light Portions Of The Image Are Affected By The ...
Simpsons Early Formula
Simpson's Early Formula. To Be In Absolute Contact. Further, Frame A Is Provided With Two Pegs C Fitting Two Holes D In Frame S, And Thus Ensures The Plate Always Being Replaced On The Exact Part Of The Negative Before Printed From, And So Preventing A Blurred Image. The Advantage ...
Sol Rues Of Light
Sol Rues Of Light. It Should Be Noted That There Is No Danger Of Displacement Of The Spectrum Lines By Changing The Source Of Light, Because The Image Photographed Is That Of The Slit, The Source Of Light Being Used For Illuminating It. To Get A Continuous Spec Trum A ...
Spark Spectra Of Metals
Spark Spectra Of Metals. A Very Simple Method Of Observing The Speetta Of Metals Is To Make A Spark Gap Filled With Other Gases Than Air, To Exil Amine The Effect Of These On The Spark,1 The Pressure Of The Enclosed Gases Can Also Be Varied. A Indicates The Adjusting ...
Special Apparatus
Special Apparatus. Although Good Work Is Often Done With A Hand Camera, A Stand Is Recommended, And For Most Subjects Of This Description Is Indispensable. The Camera Should Be Provided With Swing Back And Rising Front, And A Sliding Movement Of The Camera Body From Back To Front To Allow ...
Special Appliances
Special Appliances. There Are Not Many Special Appliances Made For This Kind Of Work, But Those Are Important. First Comes The Stand. The Ordinary Tripod Is Frequently Too Short For This Purpose. A Stand Capable Of Raising The Camera At Least 5 Ft. Is Necessary. The Best Plan Is To ...
Special Appliances Foe Developing
Special Appliances Foe Developing Films. There Are Several Ingenious Contrivances Intended To Facilitate The Development Of Films. Among These May Be Mentioned The Been Continued For About A Minute, The Film Should Be Reversed, And The Operation Re Peated With The Celluloid Side Downward Till Development Is Complete. This Method ...
Special Method Of Photographing
Special Method Of Photographing Opaque Objects. So Far Only Transparent Objects, Which Are Photographed By Transmitted Light, Have Been Dealt With ; Opaque Objects, Such As Etched Metals, Etc., Require To.be Illuminated By Reflected Light, And Neces Sarily The Apparatus Is Slightly Modified. The Usual Plan Of Illuminating By Reflected ...
Spectro Photograptiy
Spectro-photograptiy. 31e.ksrp,ement Of Colour, Intensities. By An Ingenious Invention Of Sir W. Abney, Any Of The Intensities Of The Various Parts Of The Spectrum Can Be Measured. The Proportionate Brightness Of The Dif Ferent Colours May Be Represented By A Curve, As Shown In Fig. 539, Which Pro As Spectro-photography ...
Stains
Stains. Many Photographic Experts Have Made This The Subject Of Research, And The Ex Periments Of Mr. C. H. Bothamley A Few Years Ago Did A Very Great Deal Towards Clearing Up Some Disputed Points. Among Other Things, He Pointed Out The Absolute Necessity Of Excluding Hypo. From All Opera ...
Star Spectra
Star Spectra. Without The Spectroscope Very Little Advance Could Have Been Made In The Knowledge Of Stellar Constitutions And Motions. As Long As Sufficient Light Can Be Obtained To Give A Visible Spectrum Or Affect A Sensitive Plate It Does Not Matter In The Slightest Degree What The Distance Of ...
Stopping Down
Stopping Down. Although The Equality Of Illumination And Depth Of Focus In The Telephoto Lens Is Improved By Stopping Down The Positive, Great Caution Must Be Observed In The Closing Of The Aperture, As Should The Aperture Be Much Smaller Than Of Its Focal Length (fl 72), Diffraction Takes Place, ...
Studio Cameras And Apparatus
Studio Cameras And Apparatus. Studio Cameras, Stands, Etc., Are Fully 16 Ft. Across, With An 8-ft. How Window. By Working Across In The Manner Shown Excellent Effects May Be Obtained. If The Face Re Quires Less Contrast, Lower Blind Marked 3 Half-way, No. 2 Less, And No. 1 Slightly. The ...
Suitable Subjects For The
Suitable Subjects For The Polahiscope. Doubly Refracting Substances Such As Starches, Horn, Hoofs, Fish Scales, And Crystals Of Tourmaline, Selenite, Quartz, Aragonite, Etc., Give Very Fine Effects With Polarised Light. Starch Granules Are Brilliantly Illuminated, And Show Black Crosses (illustrated By One Of The Plates), While Many Of The Crystals ...
Taking A Spectrum Photograph
Taking A Spectrum Photograph. A Simple Photograph May Be Obtained By The Method Illustrated In Fig. 762, Re Garding The Real Spectrum At S As The Ob Ject To Be Photographed ; A B Are The Parts Of The Spectrum Under Oi3servation, And S Is The Image Of The Spectrum. ...
Temperature
Temperature. The Influence Of Temperature On Develop Ment Is Considerable, And Exercises The Same Effect As Strong And Weak Solutions Both In Colour And Contrast ; The Former Corresponding With A High Temperature, And The Latter With A Low One. As Far As Possible, A Temperature Of 60° F. Should ...
Testing Gelatine
Testing Gelatine. The Selection Of A Suitable Gelatine Is A Most Important Matter. A Good Plan Is To Obtain A Variety Of Sample's, And Test Their Melting Point. The Following Is A Simple And Ingenious Method Of Testing Gelatine. A Solution Is Made Of Each Of The Gelatines Under Examination, ...
Testing Interiors For Exposure
Testing Interiors For Exposure. When The Exposure Meter Is Being Used To Estimate For An Interior Picture, Such As A Church Or A Room In A House, The Actino Meter Should Be Exposed In The Worst Lighted Part Of The Subject, Or, At Any Rate, The Worst-lighted Part Which Is ...
Testing The View Finder
Testing The View Finder. Although In The Better Class Of Appara Tus The Accuracy Of The Finder May Com Monly Be Relied Upon, It Is Frequently The Case That The Field Of View Included By The Finder Is Smaller Or Larger Than That Thrown On The Focussing Screen. Where This ...
The Aerograph Or Air
The Aerograph Or Air "brush." This Is An Apparatus For Spraying Fluid Colours On To Any Surface, By Which A Beautifully Stippled Effect Can Be Produced With A Minimum Of Trouble. Fig. 465 Shows Sketch, Just To See How It Will Come. Now Sketch In Lightly, On The Paper, The ...
The Albumen Process
The Albumen Process. The Albumen Process, Or The Ordinary Silver Process, As It Is Usually Called By Professional Photographers, Is Capable Of Giving Most Pleasing Results, And Deserves To Be Far More Practised By Amateurs. In Quality Of Gradation And Richness Of Colour It More Than Holds Its Own When ...
The Base And Copyboard
The Base And Copyboard. A Suitable Camera Having Been Ob Tained, It Is Essential To Provide Satisfac Tory Means Of Overcoming Vibration, If There Is Any Likelihood Of Its Occurring. This May Be Accomplished By Having A Swing Bed Suspended From The Roof, As Shown By Fig. 900, Or By ...
The Camera
The Camera. For Photomicrography The Camera Is Either An Extending Or Bellows Camera, Or A Non-extending Or Box Camera ; This Is Supported On A Stand Which Is Attached To A Base Board. The Base Board Is 1 To 5 Ft. Long, About 10 In. Wide, And To 1 In. ...
The Celestial Sphere
The Celestial Sphere. In The Second Method, All Measurements Are Referred To The Centre Of The Earth, And Thus The Observer's Position On The Earth's Surface Does Not Interfere With Subsequent Comparison Of The Observa Tions Made. This System Of Measurement Depends On The Small Magnitude Of The Earth's Radius ...
The Choice Of Negative
The Choice Of Negative. The Essential Qualities In A Negative For Enlarging Are, (a) Extreme Sharpness Of Definition, Not Merely In The Centre Of The Image, But All Over The Picture ; (7)) Clear Ness Of Shadows ; (e) Proportionate Grada Tion In Both High Lights And Shadows ; (d) ...
The Complete Apparatus
The Complete Apparatus, The Apparatus For The Production Of The X-rays, Not Including The Source Of Elec Tricity, Is Shown By Fig. 919. On The Right Hand Side Is The Induction Coil, And On The Left The Glass Tube Held In Its Wooden Clip. The Connecting Wires Are Supported Upon ...
The Coude Equatorial Telescope
The Cou.de Equatorial Telescope. At Paris The Instrument Used For Photo Graphing The Moon Is The Equatorial Coude (fig. Sos). The Telescope Tube Is In Two Parts, Which Are Bent At Right Angles, While At The Elbow Is A Mirror At 45° To The Incident Light Which Reflects The Rays ...
The Dark Slide
The Dark Slide. The Dark Slide Should Be A Double One, And Its Size Will Vary With The Size Of The Ledge Of Joinery. The Base Board Is 36 In. Long, B,1 In. Wide, And In. Thick. Upon It Is Fixed A Wooden Framework With Grooves On The Top, On ...
The Developing Operation
The Developing Operation. The Operator Takes A Couple Of Plates From The Box And, Giving Them A Tap On The Bench To Dislodge Any Dust That May Have Settled On Them, Places Them, Film Side Up, In The 10 In. By 8 In. Dish. The Film Is Easily Recognised By ...
The Diffraction Grating
The Diffraction Grating. The Case Of Parallel Rays Of Light Falling On A Series Of Equally-spaced Long And Narrow Rectangular Apertures May Be Now Considered. This Arrangement Of Apertures Is Termed A Grating. By The Wave Theory It Can Be Proved That The Light Which Enters Slit S (fig. 771) ...
The Easel
The Easel. One Modification Of That Shown In Fig. 422 Consists Of An Arrangement Of Rails • Tripping Over Them In The Dark. Instead Of Having The Adjustable Carrier, The Easel Itself May Be Made Adjustable Either Fur Raising Or Lowering Or Side Movements. A Novel And Convenient Form Of ...
The Enlargting Lens Or
The. Enl.argting Lens Or Objec'tive. All That Is Desirable In The Lens, In Addition To The Greatest Possible Freedom From Faults, Such As Spherical And Chrom Atic Aberration, Astigmatism And Curvature Of Field, Is That It Shall Work With As Large An Aperture As Possible, And That It Shall Cover ...
The Exposure
The Exposure. The Best Results Are Obtained By Keeping To One Source Of Light Only. The Of Light Varies Inversely As The Square Of The Distance, Therefore If The Distance From The Source Of Light Be Doubled, The Ex Posure Duration Must Be Quadrupled. Hence, To Obtain Evenly Printed Proofs ...
The Ferro Pritssiate Process
The Ferro-pritssiate Process. The Method Of Making And Using Ferro, Prussiate Paper (for Obtaining Blue Prints) Is Described Below. Prepare Two Solu Tions :—(a) Citrate Of Iron And Ammonia 1 Oz., Water 4 Oz. ; (b) Potassium Ferri Cyanide 1 Oz., Water 4 Oz. Coat Any Toler Ably Pure Paper ...
The Fixing Solution
The Fixing Solution. There Are Several Reagents Which Have The Property Of Dissolving Out The Silver Salts That Remain Unreduced By The De Veloper, The Two Principal Of Which Are Cyanide Of Potassium And Thiosulphate, Or As It Is Commonly Called, Hyposulphite Of Soda. The Latter Is Now Generally Used ...
The Hair
The Hair. This Must Be Clone In Soft, Full Strokes, With A Large Brush. Do Not, On Any Ac Count, Attempt To Indicate Separate Hairs, Because This Is Impossible ; But Endeavour To Represent Locks Of Hair, Or A Group Of Hairs Gathered Together In The Same Form. Where The ...
The Illuminant
The Illuminant. The Electric Arc Is The Most Suitable Ant For Cinematograph Projection. A Resistance, Or A Choking Coil, Properly Adjusted To The Current, Will Be Required. Where Electric Light Is Unobtainable, The Oxy-hydrogen Light May Be Employed. It Should Be Mentioned That The Leading British Insurance Companies Lutely Refuse ...
The Infallible Exposuremeter
The " Infallible" Exposure Meter. Another Good Form Of Meter Is The " In Fallible," Introduced By Geo. F. Wynne, Which Selects From The Numerous Factors Governing The Exposure Three Only—light, Plate Sensitiveness, And Stop. This Instru Ment Is Founded Upon The Same Principle As The. Watkins Exposure Meter, The ...
The Keomskop Or Photo Chromoscope
The Keomskop Or Photo-chromoscope. The Principle Of The Ives Kromskop Is Illustrated By Fig. 576, Which Is A Section Through The Apparatus. The Pictures Are Corresponding Transparencies. Compari Son Of These, One With Another, Will En Able The Principle To Be Readily Grasped. For Example, If A Red Glass Were ...
The Lippmann Procesf
The Lippmann Procesf. The Lippmann Process, Which Depends On The Effects Of The Phenomenon Known As " Interference," Was Announced By Pro Fessor Gabriel Lippmann To The French Academy Of Sciences In 1891. A Perfectly Transparent And Very Finely Grained Plate Is Placed With Its Film Side In Contact With ...
The Live
The "live Box." Many Of The Larger Water Animal Cuim Form Interesting Subjects While They Are Alive, Because They Are Quite Transparent And The Working Of The Different Organs Can Thus Be Seen ; They Must Be Enclosed In Such A Way That They Cannot Move, And This Is Effected ...
The Ozotype Process
The Ozotype Process. The Paper For This Process Can Be Pur Chased Ready For Use. It Is Said To Be Ordinary Paper Sensitised In A Solution Of Bichromate Of Potash, Manganous Sul Phate, Alum, And Boric Acid. This Paper Is Exposed Beneath A Negative, Of The Class Usually Employed For ...
The Peal Speed Tester
The Peal Speed Tester. Which The Wheel Is Travelling Being Known, The Length Of The Arc Shows The Duration Of Exposure. For Example, Fix A Small Piece Of Tinfoil To The Outer Edge Of, Say, The Front Wheel Of A Bicycle, And Place It In The Sunshine Against Something Very ...
The Permanency Of Pigments
The Permanency Of Pigments. Considering The Nature Of The Image On Which The Photographic Colourist Has To Work, It Is Hardly Necessary To Point Out The Wisdom Of Devoting Some Attention To The Permanency Of His Colours, Especially As Regards Their Chemical Composition. In Some Cases Certain Colours When Mixed ...
The Phenomenon Of Stereoscopic
The Phenomenon Of Stereoscopic Vision. Stereoscopic Vision, By Which Is Meant The Uniting Of Dissimilar Pictures With The Two Eyes Without Any Optical Agency, Appears To Be Possessed By Few People, But, By A Little Practice, The Majority May Acquire The Power. By Crossing The Axes Of The Eyes At ...
The Principle Of Photography
The Principle Of Photography Photography, As Its Name Implies, Con Sists Of Drawing By The Aid Of Light, And Is Based Upon The Fact That Various Sub Stances Undergo Such Changes In Their Con Dition As To Exhibit New Properties Under The Action Of Light. This New Property, Generally Speaking, ...
The Screen Oe Light
The Screen Oe Light Filter. Screens Suitable For Experimental Work May Be Made Very Easily. Ordinary Gela Tine Dry Plates May Have The Silver Salts Cleared Out, And The Plate After Washing Immersed In The Dye ; Thin Microscopic Glass May Be Clipped In Collodion, And After Wards Immersed In ...
The Screen As An
The Screen As An Aid To Brilliancy. Thus The Screen May Be Used To Obtain Brilliancy Quite Apart From A Considera Tion Of Colour Values, As, For Example, When Photographing Mountain Scenery, Distant Views, Or In A Veiled Atmosphere. The Shadow Light Under Such Ciremn Stances Consists Largely Of Blue ...
The Simplest Guide To
The Simplest Guide To Exposure. The Simplest Guide To Exposure Consists Of Tables Calculated Upon The Table Of The Sun's Altitudes Given On P. 95, And For The Sake Of Simplicity Letters Have Been Placed Wits Of Considerable Latitude In Exposure. For Example, If In Fig. 175 The Plate Were ...
The Single Achromatic Lens
The Single Achromatic Lens. • The Single Achromatic Lens (figs. 501 And 502) Is Always Made Of Two, Three, Or Even Four Parts Cemented Together, And Is Commonly Of A Meniscus Form. The Stop Is Generally Placed In Front, This Being Found To Be The Best Position. These Lenses Are ...
The Source Of Light
The Source Of Light. The Initial Points To Consider Are (it) Con Mience. (b) Cost, (r) Size Limit, (1) Class Tegr S, (r) Class Of Sensitive Material. . Regard To (a) This Is A Matter Best Decided By The Student Himself, And Tie Pendent Upon Local Circumstances ; Whilst (b) ...
The Studio
The Studio. The Principles Underlying The Action Of The Half-tone Screen Having Been Ex Plained, The Studio And Apparatus May Be Greater As The Camera Is Extended, Decreasing As The Latter Is Closed Up ; It Is Greater With Coarse Screens, Or Screens Having Thin Black Lines, And Less With ...
The Suns Visible Disc
The Sun's Visible Disc. The Necessity Of Having Pictures Of The Sun's Disc, Which Are Merely Representa Tions Of The Appearance Of The Surface, Has Now Sunk Into A Position Of Secondary Im Portance. Monochromatic Photographs Of Its Surface Reveal Its Chemical State, And The Analysis Of Small Areas By ...
The Telescope Carrier And
The Telescope Carrier And Table. The Arin Carrying The Telescope Is Firmly Screwed To A Large Circle Of Wood E, Which Must Be Accurately Turned Or Spoke Shaved ; And, So That The Clamp Which Bears On The Right Side May Always Have A Good Grip, The Surfaces Of The ...
The Unofocal Lens
The Unofocal Lens. This Recently Introduced Lens, Designed By Dr. Rudolph Steinheil, Of Munich, In Troduces A New Principle In The Construc Tion Of Photographic Objectives ; It Is Known As The Linofocal (fig. 525). The Necessary Corrections For Astigmatism And Besides The Various Lenses Already Re Ferred To, There ...
The Uranium Process
The Uranium Process. As This Is Not Really A Toning Process, But A Modified Form Of Intensification, It Is Essential That A Proper Print Should Be Made. It Must Be Somewhat Lighter And Weaker Than Would Be Required In The Ordinary Way, But How Much Lighter Will Depend Upon The ...
The Work Of Clerk Maxivell
The Work Of Clerk-maxivell. Professor Clerk-maxwell, In 1861, In A Lecture Delivered At The Royal Institution, Practically Demonstrated The Truth Of The Young-helmholtz Theory By Means Of Three Optical Lanterns Throwing Light Of The Three Primary Colours. It Was Shown To Be Possible To Combine The Three Coloured Lights, So ...
Three Colour Photo Ceramics
Three-colour Photo-ceramics It Is Quite Possible To Obtain A Burnt-in Picture In Natural Colours By The Exact Superposition Of A Blue, A Red, And A Yellow Picture Printed From Three Negatives Obtained Through Suitable Screens, As Described In The Section On " Photography In Colours.'' The Powder Process Appears To ...
Tiie Camera Lucida
Tiie Camera Lucida V. Photography. The Contrivance Shown By Fig. 673 Is The Ordinary Camera Nelda, Or Beale's Neutral Tint Reflector, Consisting Of A Piece Of Smoked Glass Placed At An Angle Of 45°, While Fig. 674 Shows A Prism Reflector. The Magnified Image Of The Object Being Pro Jected ...
Tiie First Cinematograph
Tiie First Cinematograph. It Was Not Until 1890 That Mr. W. Friese Greene And Mr. M. Evans Introduced What Was Practically The Predecessor Of The Modern Cinematograph. By A Special Camera They Succeeded In Obtaining A Large Number Of Negatives In Rapid Succession On A Length Of Cel Luloid Film ...