434 photogrammetric engineering - asprs...434 photogrammetric engineering it is evident that the...

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434 PHOTOGRAMMETRIC ENGINEERING it is evident that the omission of many details was necessary. I hope that some of these may be brought out in subsequent discussion. While. experience has shown that in each of the particular examples discussed, aerial photogrammetry has effected a considerable saving in both time and cost, one must be cautious in assuming that this will always be true. Local factors such as climate, extent of area, shortage of staff, political considerations and the nature of the terrain, all play their share in influenc- ing the manner in which the work can be most efficiently carried out. It should be borne in mind that photogrammetry. is still a comparatively new tool to the en- gineering profession, and any attempt by the photogrammetrist to oversell the em- ployment of this method can only result in a loss of confidence by those who do not always appreciate that like all other tools, the aerial camera and the plotting machine have their limitations. Final'ly, I express my indebtedness to the Surveyor-General of Ceylon, The Transmis- sion Engineer of the Eastern Division of the British Electricity Authority, and the Director of Surveys of the Sudan Govern- ment for permission to publish the results of projects initiated by them, and to which reference has been made in this account. GLOBAL 1\1APPING* Col. J. D. Abell, Commanding Officer, Army Map Service, Washington, D.C. ABSTRACT From the extremely localized activities of the earliest cartographers, the scope of the mapping industry has expanded until today its opeqtions have assumed a global aspect. Previewed in World War II, confirmed by the Korean War, and emphasized by the recent efforts toward international cooperation, the need for an over-all mapping preparedness program on a world-wide basis has -become imperative. As the primary military mapping agency of the United States, the Army Map Service endeavoring to accomplish such a program by increased productive capacity, an intensified research and development program, participation at national and international conferences, in- creased collaboration with foreign mapping agencies, and actual operations in far-flung parts of the world. IN PRESENTING to you a resume of the Corps of Engineers world-wide mapping efforts, one portion of my re- marks will be confined to the current progress in this direction. The other portion will be restricted to those problems inci- dental to global mapping, which still need resolving, and for which your aid is solicited. Global mapping is influenced by two requirements-economic and military. United States participation in world-wide mapping efforts coincides with: first, its search for economic resources an'd world markets; second, the necessity for pro- tecting its citizens, property and interests; third, a need to maintain military security of its mainland and outlying possessions; fourth, a need to actual or antici- pated expeditionary forces; and finally, a duty to implement those official collective actions of the United Nations. Fulfillment of this complex mapping re- quirement has been extremely difficult, time consuming and expensive. Many reasons can be cited for the inability of the United States to obtain optimum mapping coverage of those portions of the world which are vital to its interests. A few of these reasons are: The limited season and adverse weather conditioQ.s in certain areas of the world (such as the Arctic) for ground surveys and photography; inadequate logistic support because of the lack of communication facilities' (as in certain desert or mountainous regions); the dif- ficult terrain characteristics (such as dense forest growths in the tropics or * Acting for the author, Col. Elmore Lawton read this paper at 21st {\nnual Meeting of the Society, March 7-9, 1955, Hotel Shoreham, Washington, D. C.

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Page 1: 434 PHOTOGRAMMETRIC ENGINEERING - ASPRS...434 PHOTOGRAMMETRIC ENGINEERING it is evident that the omission of many details was necessary. I hope that some of these may be brought out

434 PHOTOGRAMMETRIC ENGINEERING

it is evident that the omission of manydetails was necessary. I hope that someof these may be brought out in subsequentdiscussion.

While. experience has shown that ineach of the particular examples discussed,aerial photogrammetry has effected aconsiderable saving in both time and cost,one must be cautious in assuming that thiswill always be true. Local factors such asclimate, extent of area, shortage of staff,political considerations and the nature ofthe terrain, all play their share in influenc­ing the manner in which the work can bemost efficiently carried out. It should beborne in mind that photogrammetry. is

still a comparatively new tool to the en­gineering profession, and any attempt bythe photogrammetrist to oversell the em­ployment of this method can only resultin a loss of confidence by those who do notalways appreciate that like all other tools,the aerial camera and the plotting machinehave their limitations.

Final'ly, I express my indebtedness to theSurveyor-General of Ceylon, The Transmis­sion Engineer of the Eastern Division ofthe British Electricity Authority, and theDirector of Surveys of the Sudan Govern­ment for permission to publish the resultsof projects initiated by them, and to whichreference has been made in this account.

GLOBAL 1\1APPING*

Col. J. D. Abell, Commanding Officer, Army Map Service, Washington, D.C.

ABSTRACT

From the extremely localized activities of the earliest cartographers, the scope ofthe mapping industry has expanded until today its opeqtions have assumed a globalaspect. Previewed in World War II, confirmed by the Korean War, and emphasized bythe recent efforts toward international cooperation, the need for an over-all mappingpreparedness program on a world-wide basis has -become imperative. As the primarymilitary mapping agency of the United States, the Army Map Service i~ endeavoring toaccomplish such a program by increased productive capacity, an intensified researchand development program, participation at national and international conferences, in­creased collaboration with foreign mapping agencies, and actual operations in far-flungparts of the world.

IN PRESENTING to you a resume ofthe Corps of Engineers world-wide

mapping efforts, one portion of my re­marks will be confined to the currentprogress in this direction. The other portionwill be restricted to those problems inci­dental to global mapping, which still needresolving, and for which your aid issolicited.

Global mapping is influenced by tworequirements-economic and military.United States participation in world-widemapping efforts coincides with: first, itssearch for economic resources an'd worldmarkets; second, the necessity for pro­tecting its citizens, property and interests;third, a need to maintain military securityof its mainland and outlying possessions;fourth, a need to ~ervice actual or antici-

pated expeditionary forces; and finally, aduty to implement those official collectiveactions of the United Nations.

Fulfillment of this complex mapping re­quirement has been extremely difficult,time consuming and expensive. Manyreasons can be cited for the inability of theUnited States to obtain optimum mappingcoverage of those portions of the worldwhich are vital to its interests. A few ofthese reasons are: The limited season andadverse weather conditioQ.s in certain areasof the world (such as the Arctic) for groundsurveys and photography; inadequatelogistic support because of the lack ofcommunication facilities' (as in certaindesert or mountainous regions); the dif­ficult terrain characteristics (such asdense forest growths in the tropics or

* Acting for the author, Col. Elmore Lawton read this paper at 21st {\nnual Meeting of theSociety, March 7-9, 1955, Hotel Shoreham, Washington, D. C.

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6LOBAL MAPPING 435

tundra, permafrost and glaciers in theArctic); the lack of sufficient basic groundcontrol, adjusted to a standard datum,from which photogrammetric control sur­veys could be initiated; and political bar­riers to certain areas. Needless to say,these factors are more significant now thanthey were prior to World War II. Our eco­nomic, political and military commit­ments have become more extensive andinvolved.

Recently military mappers have shownincreased interest in the northern ap­proaches to the Western Hemisphere.Strategic defense of this area has becomeoC primary concern to military planners.With this concern has come the urgentneed for precise knowledge of those largeland masses containing our early warningdevices, our listening and weather sta­tions, and our strategic air, navy and armytroops' bases. Data on the size, shape andexact geographical positions of these landmasses is vital to military planning, asis the location and character of naturalland barriers. Rel~ting these features in anaccurate and systematic pictorial form isthe primary aim of the mapper. Deter­mining the graphical scale for portrayingthese features; deciding the contour inter­val to be used for different land formations;and defining the extent to which additionalintelligence data, such as names, land­mark features, aids to navigation, etc., areto be shown, are additional factors whichare governed by the map's military use.

In other parts of the world, implementa­tion of military mapping requirementsdiffer somewhat from that of the WesternHemisphere. Overseas areas where UnitedStates troops are stationed, such as Japan,Korea, Germany and Austria, afford manyopportunities for cooperative mappingwith local agencies. Such facilities are usedwhere practicable for establishing fieldcontrol, field identification and annotationof data on aerial photographs, and fieldchecks of completed sheets. Military topo­graphic units stationed in those areasassist native mapping agencies in suchactivities and conduct map compilation,revision, and reproduction to supplementthe Army Map Service's production.

In still other countries, especially thosewith membership in the North AtlanticTreaty Organization, other forms of co­operative mapping effort are employed.In some countries, commercial or military

aircraft are procuring aerial photography;in others, local agencies are obtaining fielddata for ultimate use in map compilation;in still others, local agencies have con­tracted their services for complete map­ping, including photography, field surveysand office compilation.

Certain nations are limited in facilitiesand/or trained personnel to carry outcomplete mapping activities. Cooperativeefforts are made in such countries in anumber of ways. Aerial photography maybe flown by United States commercial ormilitary aircraft; local personnel may betrained in mapping procedures and tech­niques at United States mapping agencies,or conversely, United States techniciansmay be sent to those countries to act asinstructors or advisors in certain special­ized mapping fields.

Where' the immediate need is recon­naissance for planning purposes, and·timeprecludes obtaining adequate ground con­trol data, electronic equipment is beingused. High Precision Shoran trilaterationtechniques for extension of baiiic controlhave been used in some instances to tra­verse wide desert expanses and to tie out­lying islands into a common datum;Shoran grid network photography, withlines spaced at about SO-mile intervals, hasbeen flown in certain isolated areas as asupplement to the high-altitude verticalphotography previously obtained; and instill other cases, high-altitude Shoranphotography has been flown wherein theShoran position of the nadir point of eachphotograph has been determined. Thislatter technique, when coupled with simul­taneously recorded altimeter readings, aswell as with the addition of numerouscross flights of similar high altitude pho­tography, appears to have considerablemerit.

It may be well here to invite attentionto some of the specific contributions maderecently by the Army Map Service in thefield of mapping. They generally fall intothree major categories: (1) Direct contribu­tions to basic scientific knowledge of theearth's size and shape; (2) Technical im­provements in measuring long lines or de­termining positions on the earth's surface;and (3) Joint cooperative efforts to im­prove the world-wide mapping picture.

In the first category, contributions toscientific knowledge, the following may becited:

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436 PHOTOGRAMMETRIC ENGINEERING

(1) Continued effort to integrate andrevise the extensive geodetic tri­angulation nets with the ultimategoal of devising a best-fitting figureof the earth, which in turn will pro­vide more exact measurements ofintercontinental distances.

(2) Precise ground triangulation inareas of the world where significantgaps exist. A cooperative project ofthis kind was completed recently.I t involved closing a 630-mile sec­tion of triangulation in East Africa.This section is a part of the 4,000mile arc, along the 30th meridian be­tween the Cape of Good Hope andCairo. The arc was extended re­cently across the Mediterranean bythe use of a Hiran connection throughthe Isle of Crete to a connectionwith the European Datum. Thus wehave a 7,DDD-mile intercontinentalarc running northward from SouthAfrica, through Europe, to theArctic.

(3) The establishment of a geodeticdatum, through the efforts of nationscoordinating with the Inter-Ameri­can Geodetic Survey, for Centraland South America and its connec­tion with the North AmericanDatum. This will result in one con­tinuous arc of triangulation fromthe southern tip of South Americato the northern limits of Alaska.

In the second category, technical im­provements for measuring long distanceson the earth's surface, the following maybe cited:

(1) Intensified use of star occultationsto determine long distances on theearth. This method depends on ac­curate timing of the instant whenthe moon covers a star, as observedfrom two widely separated stations.The positions of these stations arechosen so that the same feature ofthe moon's edge cuts off the star'slight at both stations. The dis­crepancy between the observedtime and predicted time is noted,and computations are made whichyield, for each occultation, a line ofposition along which the unknownpoint must lie. At present suchoperations are being carried out inthe Pacific for the purpose of tyingvarious island groups together and

eventually tying them to the AsianMainland and the Tokyo Datum.One result should be a markedimprovement in the position ofLoran stations with a consequentimprovement in the navigation ofPacific waters.

(2) Extensive use of new instrumentswhich facilitate the determinationof precise distances and triangula­tion base lines. An example of thistype is the geodimeter-an elec­tronic optical device-which meas­ures the time interval for a lightbeam to travel to and from a mirror,located at the terminus of the lineto be measured. Utilizing this in­terval, as well as the known con­stant value of the velocity of light,it is possible to translate the datainto a distance measurement-andin a more accurate manner and inless time than by conventionalmethods. The geodimeter has thefurther advantage of making itpossible to measure distances fromone hilltop to another.

In the third category, joint cooperativeefforts to improve the world-wide mappingpicture, the following may be cited:

(1) Cooperative mapping programs tosatisfy North Atlantic Treaty Or­ganization needs. The objectives ofthese programs are uniformity ofmap symbols and standards amongthe participating nations; regularexchange of maps, source materials,reproduction material, geodetic andaerial photographic data; and theexchange of technical personnel foradvanced studies and exchange ofideas and techniques. In the samespirit of cooperation, steps arebeing taken to prepare a set ofinternational standards for maps­standards which affect all phasesof map preparation, including re­quirements for accuracy, commonsymbolization, and terminology.

(2) Similar cooperative efforts withLatin American countries are beingpromulgated. Through the Inter­American Geodetic Survey, oper­ating out of the Canal Zone, andwith active representatives locatedin seventeen countries of South andCentral America, many advancesare being made. Programs thus far

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GLOBAL MAPPING 437

initiated include establishment ofbasic geodetic and electronic tri­angulation networks, procurementof low and high altitude photog­raphy, and compilation, by stereo­photogrammetric means, of certainselected areas.

(3) The least squares adjustment of thetriangulation of the European Con­tinent and its reduction to a commongeodetic datum.

(4) The processing of thousands ofgeodetic control stations in Europeand the Far East and the publica­tion 'of many separate trig lists forthese areas.

(5) The conversion of large scale andmedium scale maps, in the conver­sion areas, to the Universal Trans­verse Mercator (UTM) Grid andthe reprinting of stock quantities.

From the foregoing statements, it isapparent that the efforts in carrying outmapping missions in various parts of theworld follow no set pattern-they areextraordinarily different in various parts ofthe world.

It is also apparent that although muchis being done to accelerate the world-widemapping program, a great deal still needsto be accomplished-some of the work tobe carried out appears to be relativelysimple-some is difficult. At this time Ipresent for your consideration a numberof problems of immediate concern to themilitary mapper.

First, the lack of capabilities for theprocurement of vertical ground control(lata of sufficient accuracy to permitproduction of 1: 25,000 scale topographicmaps for all conditions of terrain, bymeans other than conventional "on­the-ground" surveys.

Second, the lack of uniformity be­tween aerial photographic, aerial tri­angulation, and stereo-compilationequipment among the various mappingagencies of the world. Such variancesprohibit full use of all the mappingcapacity in time of emergency. Perhapsthe availability of a universal diaposi­tive printer, capable of satisfying the fullrange of variables, would be the answer.

Third, the apparent lack of uniformityin basic concepts of mapping agencies,especially as they pertain to the maps'purposes, the manner in which mapsare produced, the horizontal and vertical

accuracies required, the manner of con­ducting equipment tests, and the nomen­clature for procedures and techniques.

Fourth, the incapabilities of certainaerial triangulation and stereocompila­tion equipment to be used in conjunc­tion with heterogeneous aerial photog­raphy flown with cameras of differentfocal lengths, lens distortions, film orplate format sizes and convergentangles. The solution to this conditionwill not be met by providing such uni­versality in just the newly manufac­tured equipment but provision must bemade for the economical modificationof the large numbers already availableto the mapping agencies.

Fifth, the lack of an aerial camerastabilizing mount capable of procuringphotography with tips or tilts of lessthan 1 minute of arc. Convergent orShoran photography obtained undersuch conditions and supplemented byautomatically recorded altimeter datashould result in greater map compilationaccuracies.

Sixth, the simultaneous demand fororiginal film, to satisfy mapping andintelligence requirements, points to thenecessity of improving duplicating proc­esses. Current processes and materialsemployed result in products inferior tothe original both in photographic qualityand dimensional stability.

Seventh, the lack of techniques andprocedures for rapidly, economically and,perhaps, automatically translatingstereo-compilation data to the litho­graphic press plate without resorting tointermediate cartographic steps. Fer­haps scribing techniques or an electronic­viewing device that records map fea­tures on metallic tapes would be thesolution. An added feature of the lattermethod is that the same basic recordeddata could be used to prepare maps atdifferent scales.

Eighth, since mapping photographyis being flown at higher altitudes, thesuccess of these missions is dependent toa great extent upon overcoming, theobstacles imposed by atmospheric con­ditions. Improved films, filters andlenses must keep pace with man's in­creasing ability to fly higher.

The ninth problem relates to quicklyphoto-revising maps. Upon the begin­ning of hostilities in any area, this phase

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438 PHOTOGRAMMETRIC ENGINEERING

of map preparation becomes a majorone. Increased capability for this opera­tion is a problem deserving immediateattention.The problems which I have presented

need resolving. No individual, no singlecommercial mapping or equipment manu­facturing organization, no single govern­mental mapping agency, civilian or mili­tary, is best able to solve them. It is onlythrough collective effort, as exemplifiedby the professional interests representedhere that we can hope to reach our goal.

Perfecting the present photographic andmapping equipment and techniques andsatisfying the needs of the global require­ment are a challenge. Such a challengemust be met-it was met before by similargroups in World War II-it can be 'metagain by this one. Our stake in peacetimeis caring for the common good. Our stakein times of military emergency may wellbe common survival-of ourselves aswell as those democratic traditions wecherish.

NEWS NOTESPORTABLE PROCESSING MACHINES

Use of heliarc welding in the productionfor the Navy of portable photographicprocessing machines which will handle70 mm. 5, 51. 5!, 7 and 9-inch wide film inlengths up to 250 feet has been an­nounced by Alan Gordon, president ofGordon Enterprises, camera manufacturer,North Hollywood, Cal~fornia.

Because of the relatively strong acidsand alkalies routinely employed in photo­graphic processing, and because of thedamage from shipping and other handlingwhich the equipment may suffer, use ofheliarc welding was especially importantin manufacturing these portable machines.

The use of inert-gas welding in manu­facture of photographic equipment is arecent development. It avoids weakeningof the parent metal at the welded seamwhich occurs when the metal is heated andits chemical and physical properties changebecause of oxidation. Heliarc weldedseams are equal in strength or better thanthe strength of the parent material.

Gordon Enterprises is a prime source ofheliarc welding applications to photo­graphic equipment, having done consider­able experimental work in adapting theprocess to photographic equipment manu­facture.

SUPER CONCENTRATED LIQUID CHEMICALS

FOR PHOTOGRAPHIC USE

Announcement of superior chemicals forstabilization processing of oscillograph,electrocardiograph and seismographic re­cording materials has been made by thePhoto Concentrates, Inc. of Peekskill,N. Y.

The company recently became associ-

ated with the Oscar Fisher Company as anadjunct to its operations in the photo­graphic processing equipment field.

In announcing the Association of thetwo companies, Mr. Kinsler, President ofPhoto Concentrates and Mr. Fisher, Presi­dent of Oscar Fisher Company stated thatthe chain to complete integrated photo­graphic processing is now completed. Theuse of modern high speed chemicals makesthe design of superior processing equip­ment possible, at the same time that itmakes possible the thorough testing andevaluation in modern equipment of mod­ern photo chemicals. The officers believethat superior chemicals, as well as superiorequipment, will be the result of this associ­ation.

BEVERLEY DEVISED FOR ARCTIC

TRANSPORT

A tanker configuration of the BlackburnBeverley transport has been devised byField Aviation Company Limited, of Osh­awa, jointly with the English manufac­turer, for the continuing supply of Arcticoutposts. According to Hunting AssociatesLimited of Toronto, Ontario, considerableinterest in the application of this aircraftto Canadian requirements has been shown.

The Beverley Tanker is particularly welladapted for supplying by air all types offuel and other items to Arctic stationswhich can only be supplied by sea for, atthe most, one month a year.

The Beverley has the capacity to carrybulky items of spares and maintenanceequipment in addition to fuel. These itemsdo not have to be broken down to go in theBeverley, thus saving both manpower andtime.