US1441635A - Registering phototachymeter - Google Patents

Registering phototachymeter Download PDF

Info

Publication number
US1441635A
US1441635A US476958A US47695821A US1441635A US 1441635 A US1441635 A US 1441635A US 476958 A US476958 A US 476958A US 47695821 A US47695821 A US 47695821A US 1441635 A US1441635 A US 1441635A
Authority
US
United States
Prior art keywords
frame
objective
tele
rotation
needle
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US476958A
Inventor
Rived Francisco
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US476958A priority Critical patent/US1441635A/en
Application granted granted Critical
Publication of US1441635A publication Critical patent/US1441635A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01CMEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C3/00Measuring distances in line of sight; Optical rangefinders
    • G01C3/26Measuring distances in line of sight; Optical rangefinders using a parallactic triangle with fixed angles and a base of variable length, at, near, or formed by the object
    • G01C3/28Measuring distances in line of sight; Optical rangefinders using a parallactic triangle with fixed angles and a base of variable length, at, near, or formed by the object with provision for reduction of the distance into the horizontal plane
    • G01C3/30Measuring distances in line of sight; Optical rangefinders using a parallactic triangle with fixed angles and a base of variable length, at, near, or formed by the object with provision for reduction of the distance into the horizontal plane with adaptation to the measurement of the height of an object, e.g. tacheometers

Definitions

  • Fig 1 is a section of the whole apparatus
  • Fig. 2 is a horizontal projection of the interior of the indicator
  • Fig. 3 is a projective View of the rear part of the photographic camera
  • F ig 4 is a representation of the aspect of the photograph in which the data are photographed or registered.
  • the apparatus consists essentially, Fig. 1, of a vertical rotary shaft e provided with a platform with levelling screws according to any of the systems used in topographical apparatus and of a pressure sci-er p and of another coincidence screw so as to be able to obtain the movements desired. either rapid or slow, as in the usual. tachynmters.
  • the small. plate -l and upon it are one or more air levels or the like, which are not shown in the figure, so as to determine the horizontal. position of the small plate.
  • the said tele-objective will be provided with a sight which may be an eyepiece, with. alidades or with any other system and which will be placed above the teleobjective or laterally.
  • the box -C for the indicator or compass closed at its upper portion by a ground glass 0 and at its lower part by a transparent glass c-.
  • the magnetic needle M is mounted on the transparent glass c" and carries in its axis and in the whole of its thickness :1 saw cut S (Fig. 2) provided in one of its sides with a boring tor any other sign which serves to distinguish th north point from the south.
  • the plane of the compass box is parallel to that of the plate P.
  • FIG. 1 In the upright or the like (Fig. 1) there is an object glass --0 with a mounting provided with a total reflecting prism -P7 the two cathetic faces of which are respectively perpendicular to the optical axis of the object glass -0 and to the vertical turning axis of the apparatus.
  • prism P may be replaced by mirrors the planes of which occupy the positions of the ljiypothenuse faces of the prisms.
  • a camera obscura (ldivided by a divisory partition (similar to those used in the charm bers of stcreoscopes), with a small curtain obturator -0- and with a chassis or frame for the film Ch or with various frames for plates.
  • This camera is so adjusted that the plane, in which the images proportioned by the object glass -0 and the tele-objective -T- are formed, may be vertical when the small plate -P- is horizontal.
  • the camera obscura carries in its rear part- (Fig. 3) an opaque screen 0 the plane of which is parallel to that of the film or sensitized surface and very close to this latter and which only leaves uncovered two small circles -A and -A-- each of which bears two notches or incisions --a and 41 and 7- and at the extrcn'iities of their vertical diameters or in any needle pivotally carried in a horizontal position by the frame, means carried by the frame for projecting an image of the compass needle position in a direction parallel to the image forming rays projected from the tele-objective, and a photographic camera containing a sensitized film carried by the frame in a position to photographically record the image of the compass and the image projected by the tele-objective. when in any relative positions.
  • a supporting frame means for supporting the frame for rotation about a vertical axis.
  • a tele-ol'ijective carried by said frame for rotation about a horizontal axis.
  • a compass needle pivotally carried in a horizontal position by the frame, means carried by the frame for projecting an image of the compass needle position in a direction parallel to the image forming rays projected from the tele-objective, and a photographic camera containing a sensitized film carried by the frame in a position to photographically record the image of the compass and the image projected by the tele-objective when in any relative positions.
  • said camera having therein a screen with reference marks thereon which are photographed upon the film simultaneously with the images for reference in measuring the angles of the images from known reference lines.
  • a supporting frame means for supporting the frame for rotation about a vertical axis, a tele-objective carried by said frame for rotation about a horizontal axis, a compass needle pivotally carried in a horizontal posi tion by the frame, means carried by the frame, for projecting an image of the com pass needle position in a direction parallel to the image forming rays projected from the tele-objective, and a photographic camera containing a sensitized film carried by the frame in a position to photographically record the image of the compass and the image projected by the tele-objective when in any relative positions, said camera having therein. a partition for preventing confusion of the luminous rays forming the two images.
  • tele-objective a compass needle
  • frame for supporting the needle for rotation about a vertical axis and the tele-objective for rotation about a horizontal axis
  • means for supporting the frame for rotation about a vertical axis means for pro ecting an image of the compass needle position, and means for photographically recording the images from the tele-objective and the said projecting means.
  • a tele-objective In a registering photo-tacliymeter. a tele-objective. a compass needle. a frame for supporting the needle for rotation about a vertical axis and the tele-objective for rotation about a horizontal axis, means for sup porting the frame for rotation about a vertical axis, means for projecting an image of the compass needle position, and means for photographically recording upon the same film the images from the tele-objective and the said projecting means.
  • a tele-objective a compass needle
  • a frame for supporting the needle for rotation about a vertical axis and the tele-objective for rotation about a horizontal axis means for supporting the frame for rotation about a vertical axis, means for projecting an image of the compass needle position, and a photographic camera carried by the frame and supporting a sensitized film in a position to receive and photographically record the im ages from the tele-objective and said projecting means.
  • a tele-objective In a registering photo-tachymeter, a tele-objective. a. compass needle. a frame for supporting the needle for rotation about a vertical axis and the tele-objective for rotation about a horizontal axis, means for supporting the frame for rotation about a vertical axis, means for projecting an image of the compass needle position, and a photographic camera carried by the frame and supporting a sensitized film in a position to receive and photographically record the images from the tele-objective and said projecting means, said camera having therein a partition to prevent confusion of the luminous rays forming the separate images.
  • a registering photo-tachymeter a tele-objective, a compass needle, a frame for supporting the needle for rotation about a vertical axis and the tele-objective for rota tion about a horizontal axis, means for supporting the frame'for rotation about a vertical axis, means for projecting an image of the compass needle position, and a photographic camera carried by the frame and supporting a sensitized film in a position to receive and photographically record the images from the tele-objective and said projecting means, said camera having shutter devices for causing the recordation of the. images to take place at any desired instant.
  • a registering photo-tachymeter a tele-objective, a compass needle, a frame for supporting the needle for rotation about a vertical axisand the tele-objective for rotation about a horizontal axis, means for supporting the frame for rotation about a vertical axis, means for projecting an image of the compass needle position, means for photographically recording the images from the tele-objective, and the said projecting means, and means for photographing measuring reference marks upon the film simultaneously with the images.
  • a frame means for supporting the frame for rotation about a vertical axis, a compass needle carried by the frame for rotation about a vertical axis, a ground glass supported on the frame above said needle, a camera carriec at one side of the frame and having a sensitized photographic recording surface, a total reflectingprism supported beneath the needle for projecting the vertical rays of light from the needle in a horizontal direction.
  • a tele-objective carried by the frame for rotation about a horizontal axis, said tele-objective having a ray receiving barrel extending radially to the horizontal axis of its rotation and a reflecting prism at the juncture of the radial and horizontal sections of the samefor projecting the image forming rays through the horizontal section upon the recording surface of the camera,
  • a 1 me means for supporting the frame for 'otation about a vertical axis, a compass needle carried by the frame for rotation about a vertical axis, a ground glass supported on the frame above said needle, a camera carried at one side of the frame and l g a sensiczed photographic recording; a total reflecting prism supported 10 needle for projecting the vertical of li, it from the needle in a horizontal .ection, means for forming the horizonu ly projected rays into an image of the needle upon the said recording surface, a te ls-objective carried by the frame for rotation about a horizontal axis, said tele-objective having a ray receiving barrel extending radially to the horizontal axis of its rotation and a reflecting prism at the juncture of the radial and horizontal sections of the same for projecting: the image forming rays through the horizontal section upon the remenses cording surface of the camera, said camera
  • a frame means for supporting the frame for rotation about a vertical axis, a Cele-objective carried by the frame for rotation about a horizontal axis, said role-objective havinga portion of its barrel along the horizontal axis of rotation and the objective end at right angles to the horizontal axis whereby luminous rays from. the objects Within the range of the tele-objective during rotation of the objective end in a vertical plane Will be projected through the horizontal portion, and means for photographically recording the image formed by the rays from the teleobjective projected through the horizontal portion.
  • a frame means for supporting the frame for rotation about a vertical axis, a tele-objective carried by the frame for rotation about a horizontal axis, said tele-objective having a portion of its barrel along the horizontal axis of rotation and the objective end at right angles to the horizontal axis whereby luminous rays from the objects Within the range of the tele-objective during rotation of the objective end in a vertical plane will be projected through the horizontal portion, and a camera carried by the frame and havii 9; a sensitized rz-zcordingsurface upon which the luminous rays from the tele-obective are focused as images during rotation of the telebbjectiv'e, said camera having a shutter for exposing); the sensitized surface to the image at any instant.
  • a frame means for supporting the frame for rotation about a vertical axis, a tele-obj ective carried by the frame for rotation about a horizontal axis, said tele-objective having a portion of its barrel.
  • a camera carried by the frame and having a sensitized recording surface upon which the luminous rays from the tele-objective are-focused as images during rotation of the tele-objective, said camera having a device for printing measuring reference marks simultaneously with the printing of the image.

Description

Jan. 9, 1923.
I RiVED. REGISTERING PHOTOTACHYMETER.
FILED JUNE 1h i92l- Patented Jan. 9, 1923.
UNITED STATES FRANCISCO RIVED, OF ZARAGOZA, SPAIN.
'REGISTERING PHOTOTACHYMETER.
Application filed June 11,
T0 aZZ whom it may concern:
Be it known that I, FRANCISCO RIVED, engineer, subject of the King of Spain, residing at Zaragoza, Spain, have invented certam new and useful Improvements in Registering Phototachymeters, of which the following is a specification.
When working with any one of the tachymeters of the types hitherto known, the serious difficulty is encountered that, in taking note of the data obtained with the apparatus, an error may easily occur and false particulars be registered.
My apparatus avoids this drawback and by way of example and in its essential parts I will representit in the accompanying drawings, in which:
Fig 1 is a section of the whole apparatus;
Fig. 2 is a horizontal projection of the interior of the indicator;
Fig. 3 is a projective View of the rear part of the photographic camera, and
F ig 4 is a representation of the aspect of the photograph in which the data are photographed or registered.
Description of the apparatus.
The apparatus consists essentially, Fig. 1, of a vertical rotary shaft e provided with a platform with levelling screws according to any of the systems used in topographical apparatus and of a pressure sci-er p and of another coincidence screw so as to be able to obtain the movements desired. either rapid or slow, as in the usual. tachynmters.
linmrwably attached to the vertirai rotary shaft the small. plate -l and upon it are one or more air levels or the like, which are not shown in the figure, so as to determine the horizontal. position of the small plate.
Two uprights m and m", or other similar devices. serve as a support for the following elements:
There is a tele-objective -T- with a horizontal rotary shaft and spindle --E perpendicular to its optical axis. Qpposite the opening of the said axis or shaft there is a total reflecting prism -P- the two cathetic faces of which are respectively perpendicular to the optical axis or shaft of the tele-objective and to the horizontal turning axis. This axis is supported on the two up rights or the like -i)L-- and --m'- and provided with a pressure screw and another 1921. Serial No. 476,958.
for coincidence, which are not shown in the figure and which may be of any one of the systems used in the topographical apparatus and the object of which is to obtain the rapid and slow turning movements of the tele-objective. The said tele-objective will be provided with a sight which may be an eyepiece, with. alidades or with any other system and which will be placed above the teleobjective or laterally.
In the upper part of the uprights or the like m and --mthere is located the box -C for the indicator or compass, closed at its upper portion by a ground glass 0 and at its lower part by a transparent glass c-. The magnetic needle M is mounted on the transparent glass c" and carries in its axis and in the whole of its thickness :1 saw cut S (Fig. 2) provided in one of its sides with a boring tor any other sign which serves to distinguish th north point from the south. The plane of the compass box is parallel to that of the plate P.
In the upright or the like (Fig. 1) there is an object glass --0 with a mounting provided with a total reflecting prism -P7 the two cathetic faces of which are respectively perpendicular to the optical axis of the object glass -0 and to the vertical turning axis of the apparatus.
Not only the prism P" but also -P- may be replaced by mirrors the planes of which occupy the positions of the ljiypothenuse faces of the prisms.
Upon the upright or the like -m- (Fig 1) there is mounted a camera obscura (ldivided by a divisory partition (similar to those used in the charm bers of stcreoscopes), with a small curtain obturator -0- and with a chassis or frame for the film Ch or with various frames for plates. This camera is so adjusted that the plane, in which the images proportioned by the object glass -0 and the tele-objective -T- are formed, may be vertical when the small plate -P- is horizontal.
The camera obscura carries in its rear part- (Fig. 3) an opaque screen 0 the plane of which is parallel to that of the film or sensitized surface and very close to this latter and which only leaves uncovered two small circles -A and -A-- each of which bears two notches or incisions --a and 41 and 7- and at the extrcn'iities of their vertical diameters or in any needle pivotally carried in a horizontal position by the frame, means carried by the frame for projecting an image of the compass needle position in a direction parallel to the image forming rays projected from the tele-objective, and a photographic camera containing a sensitized film carried by the frame in a position to photographically record the image of the compass and the image projected by the tele-objective. when in any relative positions.
2. In a registering photo-tachymeter, a supporting frame, means for supporting the frame for rotation about a vertical axis. a tele-ol'ijective carried by said frame for rotation about a horizontal axis. a compass needle pivotally carried in a horizontal position by the frame, means carried by the frame for projecting an image of the compass needle position in a direction parallel to the image forming rays projected from the tele-objective, and a photographic camera containing a sensitized film carried by the frame in a position to photographically record the image of the compass and the image projected by the tele-objective when in any relative positions. said camera having therein a screen with reference marks thereon which are photographed upon the film simultaneously with the images for reference in measuring the angles of the images from known reference lines.
3. In a registering photo-tachymeter, a supporting frame, means for supporting the frame for rotation about a vertical axis, a tele-objective carried by said frame for rotation about a horizontal axis, a compass needle pivotally carried in a horizontal posi tion by the frame, means carried by the frame, for projecting an image of the com pass needle position in a direction parallel to the image forming rays projected from the tele-objective, and a photographic camera containing a sensitized film carried by the frame in a position to photographically record the image of the compass and the image projected by the tele-objective when in any relative positions, said camera having therein. a partition for preventing confusion of the luminous rays forming the two images.
4.111 a registering photo-tachymeter, a
tele-objective, a compass needle, a frame for supporting the needle for rotation about a vertical axis and the tele-objective for rotation about a horizontal axis, means for supporting the frame for rotation about a vertical axis, means for pro ecting an image of the compass needle position, and means for photographically recording the images from the tele-objective and the said projecting means.
5. In a registering photo-tacliymeter. a tele-objective. a compass needle. a frame for supporting the needle for rotation about a vertical axis and the tele-objective for rotation about a horizontal axis, means for sup porting the frame for rotation about a vertical axis, means for projecting an image of the compass needle position, and means for photographically recording upon the same film the images from the tele-objective and the said projecting means.
6. In a registering photo-tachymeter, a tele-objective a compass needle, a frame for supporting the needle for rotation about a vertical axis and the tele-objective for rotation about a horizontal axis, means for supporting the frame for rotation about a vertical axis, means for projecting an image of the compass needle position, and a photographic camera carried by the frame and supporting a sensitized film in a position to receive and photographically record the im ages from the tele-objective and said projecting means.
7. In a registering photo-tachymeter, a tele-objective. a. compass needle. a frame for supporting the needle for rotation about a vertical axis and the tele-objective for rotation about a horizontal axis, means for supporting the frame for rotation about a vertical axis, means for projecting an image of the compass needle position, and a photographic camera carried by the frame and supporting a sensitized film in a position to receive and photographically record the images from the tele-objective and said projecting means, said camera having therein a partition to prevent confusion of the luminous rays forming the separate images.
8. In a registering photo-tachymeter, a tele-objective, a compass needle, a frame for supporting the needle for rotation about a vertical axis and the tele-objective for rota tion about a horizontal axis, means for supporting the frame'for rotation about a vertical axis, means for projecting an image of the compass needle position, and a photographic camera carried by the frame and supporting a sensitized film in a position to receive and photographically record the images from the tele-objective and said projecting means, said camera having shutter devices for causing the recordation of the. images to take place at any desired instant.
9. In a registering photo-tachymeter, a tele-objective, a compass needle, a frame for supporting the needle for rotation about a vertical axisand the tele-objective for rotation about a horizontal axis, means for supporting the frame for rotation about a vertical axis, means for projecting an image of the compass needle position, means for photographically recording the images from the tele-objective, and the said projecting means, and means for photographing measuring reference marks upon the film simultaneously with the images.
10. In a registering photo-tachymeter, a
frame, means for supporting the frame for rotation about a vertical axis, a compass needle carried by the frame for rotation about vertical axis, a ground glass supported on the frame above said needle, a camera carried at one side of the frame and having a sensitizedphotographic recording surface, a total reflecting prism supported beneath the needle for projecting the vertical rays of light from the needle in a horizontal direction, and means for forming the horizontally projected rays into an image of the needle upon the said recording surface.
11. in a registering photo-tachymeter, a frame, means for supporting the frame for rotation about a vertical axis, a compass needle carried by the frame for rotation about a vertical axis, a ground glass supported on the frame above said needle, a camera carriec at one side of the frame and having a sensitized photographic recording surface, a total reflectingprism supported beneath the needle for projecting the vertical rays of light from the needle in a horizontal direction. means for fori'ninu' the horizontally projected rays into an image of the needle upon the said recording surface, a tele-objective carried by the frame for rotation about a horizontal axis, said tele-objective having a ray receiving barrel extending radially to the horizontal axis of its rotation and a reflecting prism at the juncture of the radial and horizontal sections of the samefor projecting the image forming rays through the horizontal section upon the recording surface of the camera,
12. in a registering photo-tachymeter, a 1 me, means for supporting the frame for 'otation about a vertical axis, a compass needle carried by the frame for rotation about a vertical axis, a ground glass supported on the frame above said needle, a camera carried at one side of the frame and l g a sensiczed photographic recording; a total reflecting prism supported 10 needle for projecting the vertical of li, it from the needle in a horizontal .ection, means for forming the horizonu ly projected rays into an image of the needle upon the said recording surface, a te ls-objective carried by the frame for rotation about a horizontal axis, said tele-objective having a ray receiving barrel extending radially to the horizontal axis of its rotation and a reflecting prism at the juncture of the radial and horizontal sections of the same for projecting: the image forming rays through the horizontal section upon the remenses cording surface of the camera, said camera having a partition Wall to prevent confusion of the rays forming the two images.
13. In a registering photo-tachymeter, a frame, means for supporting the frame for rotation about a vertical axis, a Cele-objective carried by the frame for rotation about a horizontal axis, said role-objective havinga portion of its barrel along the horizontal axis of rotation and the objective end at right angles to the horizontal axis whereby luminous rays from. the objects Within the range of the tele-objective during rotation of the objective end in a vertical plane Will be projected through the horizontal portion, and means for photographically recording the image formed by the rays from the teleobjective projected through the horizontal portion.
ll. In a registering photo-tachym'eter, a frame, means for supporting the frame for rotation about a vertical axis, a tele-objective carried by the frame for rotation about a horizontal axis, said tele-objective having a portion of its barrel along the horizontal axis of rotation and the objective end at right angles to the horizontal axis whereby luminous rays from the objects Within the range of the tele-objective during rotation of the objective end in a vertical plane will be projected through the horizontal portion, and a camera carried by the frame and havii 9; a sensitized rz-zcordingsurface upon which the luminous rays from the tele-obective are focused as images during rotation of the telebbjectiv'e, said camera having a shutter for exposing); the sensitized surface to the image at any instant.
15. In a registering photo-tachymeter, a frame, means for supporting the frame for rotation about a vertical axis, a tele-obj ective carried by the frame for rotation about a horizontal axis, said tele-objective having a portion of its barrel. along the horizontal axis of rotation and the objective end at right angles to the'horizontal axis, whereby luminous rays from the objects Within the auge of the tele-objective during; rotation of he objective end in a vertical plane will be irojected through the horizontal portion, 1 d a camera carried by the frame and having a sensitized recording surface upon which the luminous rays from the tele-objective are-focused as images during rotation of the tele-objective, said camera having a device for printing measuring reference marks simultaneously with the printing of the image.
In testimony whereof I affix my Signature.
FRANCISCO BIVED.
US476958A 1921-06-11 1921-06-11 Registering phototachymeter Expired - Lifetime US1441635A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US476958A US1441635A (en) 1921-06-11 1921-06-11 Registering phototachymeter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US476958A US1441635A (en) 1921-06-11 1921-06-11 Registering phototachymeter

Publications (1)

Publication Number Publication Date
US1441635A true US1441635A (en) 1923-01-09

Family

ID=23893929

Family Applications (1)

Application Number Title Priority Date Filing Date
US476958A Expired - Lifetime US1441635A (en) 1921-06-11 1921-06-11 Registering phototachymeter

Country Status (1)

Country Link
US (1) US1441635A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2501538A (en) * 1945-04-09 1950-03-21 Ruska Instr Corp Magnetic measuring instrument
US2752782A (en) * 1952-02-15 1956-07-03 Tno Device for inspecting and recording the appearance of threads and yarns
US2871089A (en) * 1952-11-28 1959-01-27 Socony Mobil Oil Co Inc Recording camera for monitoring seismic waves

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2501538A (en) * 1945-04-09 1950-03-21 Ruska Instr Corp Magnetic measuring instrument
US2752782A (en) * 1952-02-15 1956-07-03 Tno Device for inspecting and recording the appearance of threads and yarns
US2871089A (en) * 1952-11-28 1959-01-27 Socony Mobil Oil Co Inc Recording camera for monitoring seismic waves

Similar Documents

Publication Publication Date Title
US2085498A (en) Device and method for aerial survey
US1441635A (en) Registering phototachymeter
US2384666A (en) Astronomical camera
US2817994A (en) Aerial viewing apparatus
US1626787A (en) Method and appaeaws foe effecting optical projections
US2625074A (en) Photogrammetrical plotting projector apparatus for radial nadir point triangulation
US1699136A (en) eliel
US2352176A (en) Photographic arrangement
US2585451A (en) Footage indicator in a motionpicture camera viewer
US1410127A (en) Apparatus for correcting and reproducing aerial photographs
US3522611A (en) Photographic traffic monitoring device
US2165402A (en) Photographic camera
US1420440A (en) Camera applicable to aerial photography
US2893123A (en) Cinetheodolites
US2296928A (en) Projecting apparatus
US2520758A (en) Parallax correction lenticular
US1558585A (en) Method and stereoscopic device for producing objects
US2330613A (en) Light meter for cameras
US1653585A (en) Camera sextant
US2523050A (en) Method and apparatus used in
US1420439A (en) Camera
US2992599A (en) Viewfinder
US1546372A (en) Apparatus for aerial photography
US1964622A (en) Direction finder for stereoscopic cameras
US1894953A (en) Art of making maps from photographs