USRE22881E - Method of photographically re - Google Patents

Description

L. DEL RICCIO Re. 22,881 METHOD OF PHOTOGRAPHICALLY RECORDING THE May 20, 1947.

- ORDER OF PASSAGE 0F MOVING OBJECTS Origmal Flled March 20, 1939 4 Sheets-Sheet 1 INVENTOR zaenvza 0621716610 Amman:

Re. 22,881 RDING THE 4 Sheets-Shut '2 INVENTOR taefivzo 0a I/cc/o L. DEL RlCClO Original Filed March 20. 1939 ORDER OF PASSAGE 0F MOVING OBJECTS METHOD OF PHOTOGRAPHICALLY RECO I IIII II II III/I IIIIIIIIIIII III/IIIIIIIIII IIIIIIIIIIIIII May 20, 1947.

ATTURNEYS I 1 [1111/ IIIIIIII IIIIIIIIIIII II/n \D May 20, 1947; DEL n cc o Re. 22,881

METHOD OF PHOTOGRAPHICALLY RECORDING THE ORDER OF PASSAGE OF MOVING OBJECTS Original Filed March 20, 1939 4 Sheets-Sheet 3 I N VE N TOR duet/v20 an fl/cc/o ATTORNE W May 20, 1947. E Re. 22,88 1 METHOD OF PHOTOGRAPHICALLY RECORDING THE ORDER OF PASSAGE OF MOVING OBJECTS Original Filed larch 20. 1939 4 Sheets-Sheet 4 INVENTOR [0:51:20 Adi/cw A'rroxmms Reissued May 20, 1947 METHOD OF PHOTOGRAPHICALLY RE- COBDING THE ORDER (PF PASSAGE OF MOVING OBJECTS Lorenzo Del Riccio, Los Angeles, Calif., assignor of one-half to Kent Allen, Los Angeles, Calif.

Original No. 2,382,617, dated August 14, 1945, Se-

rial No. 489,424, May 28, 1943, which is a division of Serial No. 262,891, March 20, 1939, now

Patent No. 2,320,350, dated June 1, 1943.

plication for reissue August 6, 1946, Serial No.

12 Claims.

This invention relates to a photographic method and has for its chief object to provide a method, and means for carrying out the method, of making a photographic record of a succession. of moving objects as they cross a given line so that said objects are pictorially represented on a sensitized surface in terms of the relative order and time in and at which they passed such line, this case being a division of my application, Serial axis of the camera but comprises the usual broad angular field of view of a camera, the nose of a horse furthest across the track from the camera, for instance, may appear in the finished picture as ahead of or behind that of the horse nearest to the camera When in fact they may be both in line, or the horse who appears to be in advance of the other ma in fact be behind him.

The camera used in the present invention,

Number 262,891, filed March 20, 1939, now Pat- 10 however, differs essentially from such motion ent Number 2,320,350 issued June 1, 1943, picture cameras and has no such defect, for in- Said invention has for one of its purposes to stead of DhOtOgrephing the fin sh f t di e provide a, m th for the ur t ti in nd ent contestants intermittently on a series of judging of races of arious types uch a of successive individual frames, the camera used in runners, horses, automobiles and the like, where is the present inven n continuously p r ph by a continuous picture is obtained of all the 0111 a travelling lm only the passage Of t e contestants in the order in which they crossed testents ss the finish line, the field f the finish line and thus enable the judges and posure of the travelling film bein limited to the spectators to visually, conveniently and acvery narrow line representing fi f View curately determine from said picture the resuh equivalent to little more than the finish line itof such a contest without the possibility of error Self- Thus the resultant P ph Sh S t that is attendant upon a judgment b d upon contestants strung out in the order in which each visual perception of the actual contest itself, parof them finished d pa d m ch ot ticularly where t result is close, in the photograph a distance proportional to the The means heretofore used for that purpose time between their respective finisheshave been high speed motion picture cam ras A further object is to provide a method in which are set up at one end of the finish line which the e phetographicrecord of such conof race track with the axis of its lens in the tests is simultaneously made upon two sensitive same vertical plane as the finish line, and as the strips, one of vWiiith may be transparent fi competing horses, for instance, approach and from which Prints and enlargements y be cross the finish line, a series of intermittent exmade which y be developed o a r versed posures are madeon a length of motion picture positive and projected on a large screen so that m fro which the fini h of the race m be large numbers of attending spectators may View reproduced at a convenient speed to enable the and the other a Strip of photographiqpapel' jud es to decide the question as the Order which may be developed into a reversed positive in which the horse finished, or an enlargement examined by the judges in making their could be made of the particular fram showing cision with respect to the outcome of the conthe leading horse directly on the finish line. t Said strips being Put through the develop- Such cameras are however, in many respects m process immediately at the end of each race. unsuitable for that purpose, particularly since 40 The film used may be Ordinary black d te there is a space of time between successive inm infm'red sensitive film When light 0011- dividual pictures during which there is no record ditlensrequire it r @0101" film for transparency made of the position of the horses, which may proiectlonbe the precise moment in which the foremost Another Object s to vide a method Wherehorses crossed the finish line and the preceding by the field 0f VieW photflgraiphed y Said Camera, and succeeding pictures may not correctly show when t ca era is placed in its prope operating their relative positions as determinative of the position where its optical axis is substantially in result in a close race. Moreover, pictures taken e same vertical plan as e finish l is with such a camera may involve error du to fined to a very narrow strip of substantially parallax, since a photograph of lines extending 5 the same width throug out from e ou d longitudinally of the camera will represent them adjacent the camera on one side of the track as converging, and when the field of view of the 0 t background n the stant side of the camera is not confined to a single narrow strip of track. even width extending across the track in sub- Another object is to provide a method whereby stantially the same vertical plane as the optical the photographic record made by said camera distant points along the finish line W111 fall. The width of the slit will vary with the position of the and during their rest periods said film and paper strip are exposed to the light entering by the camera, as, for instance, its distance from the track, the width of the track, and other circumstances. In any case, its width will be as narrow as possible consistent with a proper exposure of the traveling film or paper strip behind it. I

This is illustrated in Fig. 9 in which the finish line is marked a and the field of view to be covered by the camera lens L is to be limited to a narrow strip of uniform width bounded by the vertical planes defined by the lines a and a on one side and the lines b and b on the other. It will be seen that if the width of the exposure area of the film is that defined by the two parallel vertical lines a: and y, the image projected by the lens L willbe that of the field included within the vertical planes a a' and cc'; Whereas by inclining the edge of the slit towards the end thereof which will receive the image of the background as shown by the line a, the portion of the field lying between the vertical plane b-b' and c-c will be excluded from registering on a sensitive surface behind the aperture In other words, let the finish line be represented by a and let b, a short distance to one side of-a and parallel thereto define the width of a narrow band of uniform width extending across a racetrack, the beginning and end of said band, together with the lines a and b, forming a long, narrow rectangle. With the camera arranged so that the line a is in the same vertical plane with the optical axis of the lens L, the distance between a and b at the end nearest the lens would be represented by the line 1), the length of the line a by y, and the distance between a and b at the end further removed from the lens L would be represented by the line 10, which is much shorter than 11 due to the fact that it is at'a much greater distance from the lens L. Consequently, the line b will be projected as the line 2. Since the slit is to permit exposure only of the image of said uniform band between the lines a and b, the edge of the slit represented by the line 2 will be disposed at an angle to the line g If the vertical edges of the slit were parallel as represented by :r and y, the slit would permit exposure of a constantly diverging band defined by the lines a and c.

Mounted within the frame I and extending from the lens 4 to a second aperture 28 for the paper strip 22 is a light tube 29 through which the rays entering by the lens 4 ar confined in their passage to the surface of the travelling paper strip 22. The aperture 28 is located a short distance beyond the aperture 2| in the line of travel of said paper strip. Said light tube is bent at right angles twice along its length in accordance with the path of said rays as directed by the prisms mounted within it and has a branch 30 extending horizontally to an aperture 3| for i the film I9 similar to the aperture 28 and located the apex of the pointer portion 33 of a target 34 erected at the other end of said finish line across the track and the apex of said pointer of the mask 32 will coincide, as shown in Fig. 11, and

' will so appear on the developed fihn and paper strip exposed behind said apertures 3| and 28.

The travel of the film l9 and the paper strip 22 past the apertures 3! and 28 is intermittent lens 4 by the rotating shutter mounted on the frame 1 and having therein an opening 4| for intermittently permitting the light entering by the lens 4 to be transmitted to said apertures 28 and 3!. Said shutter 40 is so mounted as to out across the light tube 23 in a slot therein provided forthat purpose.

It is of course understood that the planes of the travelling film l9 past the apertures l1 and 3| and of the travelling paper strip past the apertures 2| and 28 are the focal planes of the lenses 3 and 4.

Said film l9 and paper strip 22 are held securely in their respective positions immediately behind the apertures ll and 3|, and 2| and 28, in the focal planes of the lenses 3 and 4, respectively, in each case by pressure plates 42 actuated by the fiat springs 43. The pressure of said flat springs 43 is adjustable by means of the nuts 43' on the threaded studs 44 soas to permit just sufiicient pressure to be applied to the film l9 and the paper strip 22 to hold them accurately in their said positions and at the same time permit them to be drawn freely across said apertures.

Located within the housing 2 on thetop of the camera box I is an electric clock preferably of the type having a motor driven by alternating current of controlled frequency and comprising a field electromagnet 45 and a permanent magnet armature 46 which is caused to rotate in step with the alternations of the electric current. Connected to said armature by suitable gearing is the rotating disc 4! bearing on its face notations of time in terms, for example, of A; of a second. Mounted on the other face of said disc immediately opposite each of said' time notations is a series of switch points 48 adapted to make contact successively with the stationary contact spring 49 and thus close an electric circuit which includes a suitable source of current 53 and an electric lamp 5|, preferably a neon lamp, so that as the disc 41 rotates the successive time notations thereon are illuminated by the intermittent flashing of the lamp 5| whose beams are directed towards said time notation by the condenser 52. 53 is a lens whereby beams of light corresponding to the successive images of the said time notations are projected downward into the camera box through the light tube 54 to the reflecting prism 55 from which they are reflected at right angles to the pair of prisms 23 and 24 and are there split and caused to fall upon both the film l9 and paper strip 22 through the slits l1 and 2| near the wider end'of said slits which will correspond to the bottom of the finished picture. The diagonal face of the prism 55 is silvered or otherwise rendered opaque and thereby prevents the image'pmjected by the lens 3 from falling upon the marginal portion of the film l9 and the paper strip 22 which is to receive the images of the said time notations.

The speed of the said clock motor and the sizes and arrangement of the gearsby which the disc 4'! is rotated is such that the speed of said rotating disc near its periphery where said time notations are located corresponds approximately to the average speed of the travelling film l9 and paper strip 22 past the apertures l1 and iii respectively, and said time notations are spaced thereon in accordance with the time indicated thereby and the speed of rotation of said disc.

The-film- Isis preferably standard 35mm. motion-picture film, although it may be of any convenient width, and. is caused to travel froma supply reel in alight. proofhousing- 56 continuously past the slit H by meansof thesprocket '1 and intermittently past. the aperture- 3| by the sprocket 58w-after which'it is fedcontinuously by the sprocket 59 either toa take-upreellocated in the lightproof housing 60'- anddriven by the belt 61 from a pulley ontheshaftof the sprocket 59,-tordirectly into a developing-tank or machine installed near thecamera. Idle pressure rollers 62, 63 and 64 cooperate with the.

sprockets 51, 58 and 59 to hold the film I9 on said sprockets.

The paper strip 22 is preferably ofthe same size' as the film l9 and. provided withsprocket holes. It is caused to travel-inthe samemanner' and in the same. direction'andlat thesame speedas the film I9 from a-supplyreel in a lightproof housing 65 continuously past: the slit 2l -by means 0f-the sprocket 66 and intermittently past the aperture28 by the sprocket 61 after which it is fed continuously by' the sprocket-6% either to a-take-upreel located in thelightproof-housing=fi9'-and driven by the belt HI-from a pulley on the shaft of the sprocket 68, or, in the same-way as-the film l9, directly into a-developing, tank or machine. Idle pressure rollers-62f, 63 andtt' cooperate Withthe sprockets, 51 and 68 to hold the paper stripv 2 2 on said sprockets.

The rotation of the sprockets 51, 58; 59, 66; 61 and 68,-as well as the rotary shutter lll is effected by the-electric motor H1 which is mounted on-a suitable base within thecamera-box- On the end of the. armature shaft of said motor 10 towardsthe front. of the. camera is mounted a locking disc 12 and a crank arm 13 provided with a driving pin 14' engaging with the star-wheelli, thus providinga Geneva movement for the intermitt'ent rotationof thevertical shaft Tfithrough a pair of spiral gears 'I'I and'l'tlattachedto said star-wheel 15' and shaft 16' respectively. Said shaft carries thefilm sprocket 58 and at its upper end'a bevelgear '80 meshes with the bevel gear 8|" attached-tonne end'of'the shaft which carries the paper strip sprocket 6'1; The relative sixes ofthe aforesaid'gears is suc'h'that" the film and paper stripare each'advanced th'e'dis tance of one frame 'with'each revolution of the armature shaft of the'motor l0, and-held at rest while an exposure ismade-by'the synchronous rotationof the rotary shutter 49. The-rotary shutter is operatively connected tofthe front end of the armature shaft" of the motorllV'by means of the bevel'gears 8land' 93 the-shaft 89 and the. bevel gears 85' anddlir The continuous drive for the film sprockets 51 and: and for the paper strip sprockets and 68is taken fromttheiotherl andrear end of the armature shaft of the: motor 19' to 'which'is. op eratively. connected. bya-pair of spiral gears'lli and B8 the vertical'shaft- 8'9.which carriesv the thepaper stripsprocket 5 6, and drives. thQVBlL- tical'shaft I09, carrying the.filin..s procket 51, by means ofapa'ir ofbevel gears l0] andllulattached to the adjacent ends of the shafts 98. and

I00 respectively. p

The speed or travel of both. the film I9 and the paper strip 22 from their respective supply reels past their respective apertures for bestpictorial results should be approximately the same as the'speed of'the images of the horsesor other contestants past the slits l1 and 2|, and it has been found by experiment that all of the said sprockets may be of the same size and rotate at the samenumber of revolutions per minute, since the variation insuch speed of the film 19' and paper strip 22 past the slits I1 and 2| as called for by. the speedof. a slower type of contestants suchas runners, forexample, and a faster type of contestants, such as automobiles, for example, will not affect the exposure at the apertures 3| and 28 beyondlthe ordinary range of adjustment of the stop opening of. the lens-4 to-correct it,.or the setting of the rheostat I93 which controls the speed of themotor 10" may be changed when exposing through the lens 4 to give the proper exposure at the apertures 31 and'28' since there isno movement of the targetwhichis photographed throughsaid apertures 3| and'ZBI To make a photographic record of the finish ofa-horsev race, for example, in accordancewith the invention, the camera, suitably threaded with a supply of sensitive film andpaper strip, is rigidly mounted'on asuitable immovable support on one side of the track at the finish line and at a height slightly above that'of the horses and pointed at a' slight angle. downward so as to embrace. a view of all the horses and to avoidthe view of one horse being occluded by another horse closer to the camera. The side of the track on which-the camera isto be placed will-be determined by the direction in which the race isrun, since it is necessary that the travel of the film and paper strip be. in the opposite direction. The

camera is-so positioned that the optical axes of its1enses3and4 are at right anglesto the course of saidItrackand-thati the vertical plane of said axes intersect the apex of the pointer 33 of the target 34' which is positioned at the end of the finish line on the other side of the track; Such position. of thecamera can be readily determined by means of the telescope sight B'whose optical axis is in the same vertical plane asthose of the lensesi3 -and 4} If desired, the telescope sight 6 may be dispensed. with and the image of'the target-viewedon the back of the film |9behind the aperture 3| through an opening'3 in the back of the camera provided'for that purpose,- the pressure plate 32 behind theapertureil havingbeen temporarily removed for that purpose andthe position-of the camera adjusted until'the apex of the pointer 33 coincides with the apex of the pointer of the mask 32; In this position the fixed edge of the slit formed byftheplate 25 is in the vertical plane of the finish line and the width of the slit extends therefrom in the same direction as the. travel of the film I9- and the paper strip 22. The said slit is then adjusted toth'e desired width and the angular adjustment of the opposite edge is. made so as to confine the exposure area of the film and the paper strip to the imageof a narrow band of 'uniform width across the track. The extent of such angular adjustment maybe determined by calculation or by viewing the image of-the fieldon the bac-lof the film behind said slitand may beperformed manually withinthe camera.- Theslit 24 is similarly adjusted. to the same size and-shape as the'slit.

IT. Th camera is then rigidly. fastenedin its said position and is ready to be operated, the

shutter 8 being in its normal position with the lens 3 closed and the lens 4 open.

A short time before the end of the race, for instance, when the horses are coming into the homestretch, the electric motor and the electric clock which are connected to a suitable source of electric current are put in operation and a number of photographs made of the target 34 on the travelling film and paper strip through the apertures 3| and 28, thereby making a photographic record of the position of the camera with respect to said target and authenticating the fact that the subsequent exposures made on said film and paper strip through the slits l1 and 2| with the camera in the position in which it was set represent what took place exactly at the finish line.

As the horses approach the finish line a current of electricity is switched through the solenoid l4 thus causing the shutter 8 to be moved and held in the-position Where the lens 4 is closed and the lens 3 is open. It is understood that the speed of the motor has been adjusted by the rheostat [(13 so that the film l9 and paper strip 22 are traveling past the slits IT and 2| at the estimated speed at which the images of the horses will cross said slits when said horses cross the finish line, and then as the horses do cross the finish line the images of them will be registered upon the travelling film I9 and paper strip 22 in the relative order and time in which each said horse crossed the finish line. At the same time, while the film l9 and paper strip 22 are travelling past the slits l1 and 2|, the intervals'of time shown by the notations on the clock driven disc 41 are photographed on the said film and paper strip through said slits and will appear in the finished picture along the lower margin thereof. Thus the finished picture will show not only the relative order in which the horses finished, but also the difference in time between them. Such a picture is shown in Fig. 12.

It will be noted that the picture thus produced will be characterized by the absence from it of all objects or figures within the field of view of the camera lens, other than the horses themselves and their respective jockeys. Because of the continuous movement of the film and paper strip, each of the fixed objects such as the track itself, structures, the target 34, etc., and :background scenery, will not be defined or appear as such in the picture but will be present only as a formless area of a gray tone corresponding to its light intensity, extending throughout the length of the picture, while the horses whose images are moving with the film and paper strip will appear thereon in distinct form. This serves to emphasize the definition of the images of the horses so that they stand out distinctly and their relative positions are easily determined by the eye free from any confusion with images of surrounding objects.

While it is desirable that the speed of the travelling film and paper strip should be the same as that of the images of the horses as they travel across the slits in the direction of the travelling film and paper strip, it isnot essential that their respective speeds be exactly the same. If the film and paper strip should be travelling faster than the images of the horses, it will only result in distorting the picture of the horses along their length by elongating their appearance and if the film of paper strip is travelling more slowly than the images of the horses, it will result in shorten- 10 ing the length of the pictures of said horses, but the relative position of said horses and the distance in terms of the time between them in the picture will not be thereby affected.

Immediately after'the lasthorse has crossed the finish line, the solenoid circuit is opened whereby the shutter 8 is retracted by the spring 16 to its former position, and, as the camera continues to run for a short period, a number of successive photographs are again made of the target 34 through the lens 4 thus forming at the end of the race, as well as at the beginning, a satisfactory check upon the correctness of the position of the camera in recording the passage of the horses past the finish line and providing on the film and paper strip a notation of the date and number of the race or any other data appearingon the target.

Either the film [9 or the paper strip 22 or both of them are then immediately developed, preferably to produce a reversed positive, from which the judges of the race can easily determine the order in which the horses crossed the finish line and the interval of time between them, and the film may be projected on a large screen to be viewed by the" spectators. There may be a time. however, when the race is so close that the extension of the nose of one horse beyond the other is hardly discernible by the unaided eye, and as an aid for the accurate determination of such a question, the slits l1 and 2! maybe bridged near one end thereof by a thin opaque strip HM adjacent said end of the slits and at right angles thereto, which will have the effect of producing in the finished positive picture a thin black line I95 extending longitudinally alon saidfilm and paper strip from which a vertical line representing the finish line may be erected by means, for instance, of a tri-square whereby the determination may be accurately and definitely made as to the nose of which, horse occupies the more advanced position on said picture and which was therefore the first to cross the finish line. Obviously the specific details of my invention as illustrated and described may be varied in many respects without departing from the invention as defined in the appended claims.

What I claim is:

1. The method of making a photographic record of contestants crossing a finish line of a race upon a course, which comprises the steps of positioning a photographic camera to one side of and above said course with the optical axis of its objective in alignment with said finish line, continuously projecting through said objective the images of said contestants upon a light sensitive surface in said camera and at thesame time moving said sensitive surface in the same direction and at substantially the same spee'das said images and masking the said sensitive surface so that the area of exposure thereof is continuously confined to a narrow strip extending transversely of the direction of movement of said sensitive surface which is in optical correspondence with the said. finish line and an area of said course adjoining said finish line on only one side thereof.

2. The method of makinga photographic record of contestants crossing a finish line of a race upon a course, which comprises the steps of positioning a photographic camera to one side of and above said course with the optical axis of its objective in alignment with said finish line, continuously projecting through said objective the images of said contestants upon a light sensitive surface in said camera and at the same time moving said sensitive surface in the same direction and at substantially the same'speed as said images and maintaining a maskingselement in front of said sensitive surface-having an exposure'aperture in the form of a narrow slit extending tran versely of the direction of movement of said-sensitive surface, and aligning one side edge of said exposure aperture with the optical axis of said objective and with said finish line so that the area of exposure of said sensitive surface iscontinuously confined to a narrow strip extending transversely of the direction of movement of said sensitive surface whichis in optical correspondence .with the saidvfinishline and an areaof said course adjoining said finish line on only one side thereof.

'3. The method of making a photographic rec- 7 rd or contestants crossing a finish line of a race upon a course, which comprises the steps of positioning a photographictcamera to one side of and above said course with the optical axis of its objective in alignment with said finish line, continuously projecting through said objective the images of said contestants upon alight sensitive surface in said camera and at thesame time moving said sensitive surface :in the same direction and at substantially the same-speed as said images and masking the said sensitive surface so that the area of exposure thereof is continuously confined to va narrow, tapered stri extending transversely of the direction of movement of said sensitive surface which is in optical correspondence with anarrow vertical zone extending across said course; constituted on one side by said finish line and on the opposite side by a line parallel thereto and slightly spaced therefrom, the narrow part of said tapered exposed strip corresponding to the far end of said zone.

4. The method of making a photographic rec- 0rd of contestants crossing a finish line of a race upon a course, which comprises the steps of positioning a photographic camera to one side of and above said course with the optical axis of its obj ective in alignment with said finish line, continuously projecting through said objective the images of said contestants upon a light sensitive surface in said camera and at the same time moving said sensitive surface in the same-direction and at substantially the same speed as said images and masking thesaid sensitive surface so that the area of exposure thereof is continuously confined to a narrow, tapered strip extending transversely of the direction of movement of said sensitive surface, one side of which strip coincides with the said finish line and the optical axis of said objective and the opposite side is at an angle to said first side andcoincides with a line parallel to and slightly spaced from said finshed line, the narrow part of said tapered strip corresponding to the far endof said zone.

5. The method of making a photographic rec- 0rd of contestants crossing a finish line of a race upon a course, which comprises the steps of positioning a photographic camera to one side of and above said course with the optical axis of its objective in alignment with said finish line, continuously projecting through said objective the im-' ages of said contestants upon a light sensitive surface in said camera and at the same time moving said sensitive surface in the same direction and at substantially the same speed as said images and maintaining a masking element in front of said sensitive surface provided with an exposure aperture in the form of a narrow tapered slit, extending transversely of the direction of movement of said sensitive surface, aligning one side edge of said slit with the said finish line and the optical axis of said objective and aligning the opposite side of said'slit with a line parallel to and slightly spaced from said finish line whereby the exposure area of said sensitive surface will optically correspond to the narrow vertical zone across the course between said finish line and said line parallel thereto, thenarrow partOf said tapered aperture slitcorresponding to the far endof said zone.

6. The method of making a continuous still photographic record of contestants crossing a finish line of a race upon a course, which comprises positioning a photographic camera-to one side of andabove said course with the optical axis of the objective of said camera in alignment with said finish line, focusing said objective upon said finish line, continuously moving a light sensitive surface in said camera .at substantially the same speed and direction as the speed and direction of movement respectively of the images of'said contestants projected by said objective and at the same time maintaining a masking element in front of saidsensitive surface having an exposure aperture in the form of a narrow tapered slit extending transversely of the direction of movement of said surface, aligning one side edge of said aperture slit with the said finish line and the other side edge with a line parallel to and slightly spaced from said finish line so that only the images of said contestants contained'within the narrow vertical zone lying between the vertical plane including said finish line and the vertical plane including said line parallel thereto will be projected upon the exposed area of said sensitive surface and continuously photographing the contestants through said objective and exposure aperture of said masking element upon said'sensitive surface as such contestants enter and remain in said narrow vertical zone.

7. The method of making a photographic recorcl of contestants crossing agiven line of a race upon a course, which comprises the steps of positioning a photographic camera to one side of and above said course with the optical axis of its objective in alignment with said given line, continuously projecting through said objective the images of said contestants upon a light sensitive surface in said camera and at the same time moving said sensitive surface in the same direction and at substantially the same speed as said images and masking the said sensitive surface so that the area of exposure thereof is continuously confined to a narrow strip extending transversely of the direction of movement of said sensitive surface which is in optical corre spondence with the said given line and an area of said course adjoining said given line on only one side thereof. 7

8. The method of making a photographic record of contestants crossing a given line of a race upon a course, which comprises the steps of positioning a photographic camera to one side of and above said course with the optical axis of its objective in alignment with said given line, continuously projecting through said objective the images of said contestants upon a light sensitive surface in said camera and at the same time moving said sensitive surface in the same direc-' tion and at substantially the same speed as said images and maintaining a masking element in front of said sensitive surface having an exposure aperture in the form of a narrow slit extending transversely of the direction of movement of said sensitive surface, and aligning one side edge of said exposure aperture with the optical axis of said objective and with said given line so that the area of exposure of said sensitive surface is continuously confined to a narrow strip extending transversely of the direction of movement of said sensitive surface which is in optical correspondence with the said given line and an area of said course adjoining said given line on only one side thereof.

9. The method of making a photographic recrd of contestants crossing a given line of a race upon a course, which comprises the steps of po sitioning a'photographio camera to one side of and above said course with the optical axis of its objective in alignment with said given line, continuously projecting through said objective the images of said contestants upon a light sensitive surface in said camera and at the same time moving said sensitive surface in the same direction and at substantially the same speed as said images and masking the said sensitive surface so that the area of exposure thereof is continuously confined to a narrow, tapered strip extending transversely of the direction of movement of said sensitive surface which is in optical correspondence with a narrow vertical zone extending across said course, constituted on one side by said given line and on the opposite side by a line parallel thereto and slightly spaced therefrom, the narrow part of said tapered exposed strip corresponding to the far end of said zone.

10. The method of making a photographic rec- 0rd of contestants crossing a given line of a race upon a course, which comprises the steps of po sitioning a photographic camera to one side of and above said course with the optical axis of its objective in alignment with said given line, continuously projecting through said objective the images of said contestants upon a light sensitive surface in said camera and at the same time moving said sensitive surface in the same direction and at substantially the same speed as said images and masking the said sensitive surface so that the area of exposure thereof is continuously confined to a narrow, tapered strip extending transversely of the direction of movement of said sensitive surface, one side of which strip coincides with the said given line and the optical axis of said objective and the opposite side is at an angle to said first side and coincides with a line parallel to and slightly spaced from said given line, the narrow part of said tapered strip corresponding to the far end of said zone.

11. The method of making a photographic record of contestants crossing a given line of a race upon a course, which comprises the steps of positioning a photographic camera to one side of and above said course with the optical axis of its objective in alignment with said given line,

continuously projecting through said objective the images of said contestants upon a light sensitive surface in said camera and at the same time moving said sensitive surface in the same direction and at substantially the same speed as said images and maintaining a masking element in front of said sensitive surface provided with an exposure aperture in the form of a narrow tapered slit, extending transversely of the direction of movement of said sensitive surface, aligning one side edge of said slit with the said given line and the optical axis of said objective and aligning the opposite side of said slit with a line parallel to and slightly spaced from said given line whereby the exposure area of said sensitive surface will optically correspond to the narrow vertical zone across the course between said given line and said line parallel thereto, the narrow part of said tapered aperture slit corresponding to the far end ofsaid zone.

12. The method of making a continuous still photographic record of contestants crossing a given line of a race upon a course, which comprises positioning a photographic camera to one side of and above said course with the optical axis of the objective of said camera in alignment with said given line, focusing said objective upon said given line, continuously moving a light sensitive surface in said camera at substantially the same speed and direction as the speed and direction of movement respectively of the images of said contestants projected by said objective and at the same time maintaining a masking element in front of said sensitive surface having an exposure aperture in the form of a narrow tapered slit extending transversely of the direction of sitive surface as such contestants enter and remain in said narrow vertical zone.

LORENZO DEL RICCIO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,302,331 Kuprion Nov. 1'7, 1942 2,403,911 Crawley July 16, 1942

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