US 3234863 A
Description (OCR text may contain errors)
15, 1966 s. c. PETERSON ETAL 3,234,363
PHOTOGRAPHIC CONSTRUCTION RECORDS Filed March 5, 1963 1... F7610 Fla. 8 J
777777777 "777 /7 M. i /2 30; mm F/ e. 4 j
FIG. 4/ 1 IN V EN TOR. GERALD C. PETERSON, BCOkNEL/US H. HAGEMA N United States Patent This invention relates to the making of photographic, as-built plans (or records).
When large buildings, particularly commercial and industrial types in which plumbing and electrical conduits are buried, it is a standard requirement of construction contracts that plans showing the building as built be supplied. It is fortunate that these plans rarely coincide with the building as actually built, for the reason that workmen often make minor modifications on the spot either to run a conduit to a desired location or simply to accommodate a mistake made in cutting a line too long or too short. The result is that in any or most cases, much of the plumbing and electric circuitry in large buildings cannot readily be located. Experiences are legion in which large building areas have had to be torn up in the attempt to find a particular conduit.
It is an object of this invention to provide a means whereby a photographic record can be kept of concealed portions of a building, and in which these elements can be found to fractions of an inch from an examination of the picture on which a grid has been imposed.
According to this invention, a camera is utilized which has an axis, the axis being kept vertical and intersecting a datum point, whose location is known. According to a preferred but optional feature of the invention, the camera is supported by a boom so as readily to be placed at a proper altitude and location relative to a reg-ion to be photographed.
In order to provide a dimensional scale of reference, a grid of regular rectangular properties having graduations proportional to some unit of length, such as inches or feet, is spread out over an area and has a datum point therein. Then a congruent optical system such as the same camera as used for the aforementioned photography is set above this grid, and the grid is photographed. Thereafter, a composite picture is made of the picture of the region andof the grid which, because they have been photographed and then applied to a positive print through congruent optical systems, produce an as-built photograph in which all optical and dimensional errors are compensating, and in which the grid provide a reliable, proportional indication of unit measure where the object being sought is located.
The above and other features of this invention will be fully understood from the following detailed description and the accompanying drawings in which:
FIG. 1 is a plan view of a true grid utilized in this invention;
FIG. 2 is a side elevation of an optical system used in the invention;
FIGS. 3 and 4 are top and side views of types of plumbing hookups which advantageously can be photographed and their component portions located by use of this invention;
FIGS. 5-7 are side schematic views showing three printing processes useful in making an as-built photograph according to this invention;
FIGS. 8 and 9 are plan views of portions of the invent-ion;
FIG. 10 is a side schematic view of still another process for this invention; and
FIG. 11 is a section taken at line 11-11 of FIG. 10.
FIG. 1 illustrates a true grid 10 which may be made "ice of string or rope stretched tightly at equal intervals 11 which preferably are spaced by standard units of measurement such as one foot. A target 12 is placed in the middle of this grid as a datum point, the target being provided on a board 13 having a circle 14 and cross-arms 15, the center of which is the datum point. These provide for such centering as may be desired and are used to provide for compass orientation.
A camera 16 having an axis 17 is supported from a boom 18. The boom includes a tripod 19, a vertical swivel joint 20, and a hinge 21 on the joint carrying a tube 22. A boom arm 23 is slideable in the tube. The boom arm may be raised, lowered, rotated, lengthened or shortened, as required by the job.
A suspension arm 24 is hung from the free end of the boom arm to support the camera. A plumb bob 25 is supported by a flexible line 26 on the axis of the camera, preferably coincident therewith. In photographing the true grid to provide for a reference grid, the boom and camera are supported as shown in FIG. 2 with the plumb bob coincident with the center of arms 15 so that the axis is vertical and intersects the datum point. A picture may then be taken of the true grid and developed on a negative so as to provide a reference grid. The reference grid will have certain aberrations and distortions caused by the camera lens and will not itself be uniform over its entire surface. Because of the way the grid is used in this invention, these abarrations and distortions are not important.
In order to photograph a region 30 (FIG. 4) of which an as-built plan is to be made, a target 12 is placed in the region at a known distance from a bench mark 31 to act as a datum point. The dimensions from the bench mark may be those of a vector, or of rectangular coordi nates. The location of the datum point is then known, and may be found again for successive pictures of the same region. When the target is placed, the boom is placed with the camera in the same geometrical relationship to the target as it Was in FIG. 2, so that the photographic optical systems are congruent. It is evident that with this arrangement, the aberrations and distortions of the photographed region and of the photograph of the true grid are proportionally identical, and therefore cancelling, in that an error in one will not result in an error in reading the other when their datum points are coincident.
As the region is built up with additional installations, additional pictures may be taken with the target in or near the same location from time to time, so as to indicate the developing conditions within the region. The resulting photographs show the precise conditions, and not merely what a draftsman thought was built, which might have been changed on the job.
In order to produce the as-built plan, it is necessary to superimpose the reference grid on the picture of the region. There are three principal ways to do this, but in every case the images of the reference grid and of the region as photographed must pass through congruent optical systems. The term congruent optical system includes the simultaneous use of a single optical system.
FIG. 5 shows one printing technique. An enlarger 32 is conveniently used in all embodiments. In this case, the negatives 33, 34 of the photograph of the true grid and of the region, respectively, are placed in surface-tosurface contact, with the datum points coincident. The composite picture is then projected onto a piece of positive paper 35.
FIG. 6 shows the presently preferred technique, which has a number of commercial advantages which may readily be understood by a consideration of FIGS. 8 and 9. F IG. 8 shows a transparent overlay 37 which consists of the picture taken of the true grid. This is a reference grid which has been enlarged to the same size as the picture of which it is to become a part. Preferably, the picture taken of the reference grid is developed on a transparent acetate sheet, and then the lines are made black. Thereafter, when a positive print is made, the grid lines will be on the print so as to provide optimum contrast with the usual building background.
As can best be seen in FIG. 8, the reference grid 38 is provided as though it were projected as in FIG. 5. All of the distortions and aberrations will be there, but they are not shown in the drawings, because they are of relatively small size. In addition, four justification marks 39 may be provided, if desired, on the overlay.
FIG. 9 illustrates a negative 40 from the photograph of a region with justification marks 41. A convenient technique for making its dataum point coincide with that of the reference grid is to place the overlay on an easel without the positive paper 42 yet in place. Then the light is turned on in the enlarger and passed through negative 40, projecting its datum point and justification line, on those of the overlay. It is simple at this time to make either the justification marks or the targets coincide, which attends to centering and magnification problems. Thereafter the positive paper is put in place and exposed through the negative and the overlay to secure the composite picture.
Still another technique of making the positive print is shown in FIG. 7 in which an enlarger flashes its light through negatives 43, 44 of the reference grid and of the region, respectively, both of these being in surface-tosurface contact with each other, negative 44' being in surface-to-surface contact with positive paper 45.
FIG. shows that a grid 50 obtained from photographing the true grid may be placed on a transparency within the camera, and thereby placed directly upon the negative 51 produced in the camera when it photographs the region. Then any enlarger may be used to project the composite negative produced thereby onto a positive paper. This process involves certain registration difiiculties not common to the other systems shown, and is somewhat more diflicult to use. However, it is still feasible.
A suitable enlarger for this purpose is a 4 X 5 Omega, manufactured by Simm-on Bros, Inc., Long Island City, New York. A suitable camera for this purpose is a Veriwide 100 Camera, manufactured by Brooks-Plaubel of New York and Frankfurt, Germany, with a 100 superangulon 1:8/47 Schncider-Kreuznach lens. The camera will ordinarily be suspended about 13 /2 feet above the place of the true grid or region, although this may be varied. Obviously, the reference grid used will be one I which relates to the height from which the region is photographed.
FIGS. 3 and 4 illustrate the type of pipe or conduit constructions which frequently appear in building construction. When the as-built plan is finished, it will constitute a photograph of FIG. 4 overlaid with the reference grid of FIG. 8. From this reference grid, the location of a desired element within the grid can readily be derived and then with the knowledge of the location of the datum point, these can be readily located in a concealing envlronment.
FIGS. 5, 6 and 7 illustrate congruent optical systems "wherein the light simultaneously passes through the elements described. It will readily be understood that the negatives and the like could hav been derived through separate optical systems, but they will all have the same properties as to distortion, magnification and the like, thereby establishing the meaning of congruent in this specificatlon as an optical system which will produce substantially the same result with respect to the transformation of a scene of the true grid and of the region being photographed onto a common composite picture.
This invention is not to be limited by the embodiments shown in the drawings and described in the description which are given by way of example and not of limitation, but only in accordance with the scope of the appended claims.
1. A method of making photographic-as-built plans, comprising: establishing a known dataum point in a region to be photographed for a plan, suspending a camera having an axis over the datum point, with the axis vertical and intersecting the datum point, photographing the region with said camera, developing a negative therefrom, and printing a composite pitcure of said negative and of a reference grid obtained by photographing a true grid with a congruent optical system, the images of the grid and 0f the negative arriving at the location of the composite picture through congruent optical systems.
2. A method according to claim it in which the photograph of the true grid is on a negative, and in which both negatives are simultaneously projected on positive a er. p A method according to claim 1 in which a plurality of said composite pictures are secured at intervals of construction, thereby to secure a record of the identity and location of otherwise-concealed objects relative to the datum point.
4. A method according to claim 1 in which the photograph of the true grid is on a negative, and in which the negatives are overlaid in surface-to-surface contact with each other, both overlaying a sheet of positive paper, and the paper is then exposed to secure a composite picture of both negatives.
5. A method according to claim 1 in which the true grid is photographed and then projected onto a transpar ent overlay coextensive with the area of the composite picture, and in which the negative is projected onto positive paper while the paper is in sur'face-to-surface contact with the overlay.
6. A method according to claim 5 in which the grid on the overlay is opaque, whereby the reference grid on the composite picture is white in color.
7. A method of making photographic-as-built plans, comprising: forming on a planar surface a true grid having a datum point, suspending a camera having an axis, with the axis vertical and intersecting the datum point, photographing the grid, and developing the image thus produced as a reference grid with a datum point; establishing a datum point in a region to be photographed for a plan, suspending a camera having a congruent optical system and an axis, with the axis in a vertical position and intersecting the latter datum point, photographing the region with the latter camera and developing the picture thereby obtained, and printing a composite picture of the two photographs by projecting them through congruent systems to a piece of positive paper, thereby to produce a composite picture of the photographed region as it would have appeared had a true planar grid been formed on the photographed region.
8. A method according to claim 7 in which the photograph of the true grid is on a negative, and in which both negatives are simultaneously projected on positive paper.
9. A method according to claim 7 in which the grid on the overlay is opaque, whereby the reference grid on the composite picture is white in color.
10. A method according to claim 7 in which both photographs are on negatives, and in which both negatives are overlaid in surface-to-surface contact with each other, both overlaying the sheet of positive paper, the paper being exposed to secure a composite picture of both negatives.
11. A method according to claim 7 in which the true grid is photographed and then projected onto a transparent overlay coextensive with the area of the composite picture, and in which the negative is projected onto positive paper while the paper is in surface-to-surface contact with the overlay.
v12. A method according to claim 11 in which the grid 5 6 on the overlay is opaque, whereby the reference grid on 2,352,176 6/1944 Bolsey 951.1 X the composite picture is white in color. 2,807,198 9/ 1957 Resnik 951.1 13. A method according to claim 7 in which the pho- 3,110,540 11/1963 Simian 346107 X tograph of the grid is disposed on a transparency in the OTHE REFERENCES camera and superimposed on the picture of the region 5 The Encyclopedia of Photography, vol. 8, pp. 3009 made by the camera.
and 3011, Progress Engineering Photography, published by National Education Alliance, New York, 1949. Copy References Cited by the Examiner i Group 430.
UNITED STATES PATENTS 10 JOHN M. HORAN, Primary Examiner.
666,788 1/1901 erli 95-85 NORTON ANSI-1BR, Examinen