بنك الاسئلة ESR 2010 2ND 332

I-                   Define the following criteria of aerial photographs:

1-    Tone

2-    Shape

3-    Size

4-    Scale

5-    Vertical Exaggeration

Answer:

1-    Tone: Photographic tone is a measure of the relative amount of light reflected by an object and actually recorded on the black-and-white photograph.

2-    Shape: Shape concerns the general form or configuration of terrain features.

3-    Size: Size generally is defined as a measure of surface or volume dimensions of an object.

4-    Scale: Small-scale photographs

* Less detail can be discerned مَعْرُوف. 

* show a large area in a single stereoscopic model, and over-all relations

Large-scale photographs

  for most field mapping it is convenient to map on relatively large-scale photographs. It is almost unfortunate that small-scale (1:50,000 or smaller) and large-scale (1:20:000 or larger)

5- Vertical Exaggeration: The exaggeration of vertical distances with respect to horizontal distances is characteristic of almost all stereoscopic models

II-               1- What are the routine procedures applicable in using aerial    

      photographs in field mapping?

2- What are the factors affecting vertical exaggeration?

Answer:

1- the routine procedures applicable in using aerial   

      photographs in field mapping:

1-    The practice of stereoscopic viewing is extremely valuable

2-    The preparation of photographs for field use, and methods of annotating photographs and recording of field data are important.

3-    Particularly useful are methods of locating the observer's position and ground observations on the photographs.

4-    Aerial photographs are used in close conjunction with topographic base maps as well as with certain field instruments, such as an altimeter.

5-    Prior to any field study it is desirable to scan the stereoscopic models for geologic and other information; this involves interpretation techniques

2- The factors affecting vertical exaggeration:

العوامل التى تتحكم في المبالغة الرأسية:

أ- أثناء التصوير الجوي:                         

1- تتناسب المبالغة الرأسية طرديا مع القاعدة الهوائية

2- تتناسب المبالغة الرأسية طرديا مع التداخل الطولى

3- تتناسب المبالغة الرأسية عكسيا مع البعد البؤري لعدسة الة التصوير

4- تتناسب المبالغة الرأسية عكسيا مع ارتفاع الطيران      

ب- أثناء الابصار المجسم:

1- تتناسب المبالغة الرأسية طرديا مع مسافة الابصار        

2- تتناسب المبالغة الرأسية طرديا مع المسافة التى تفصل بين الصورتين

3- تتناسب المبالغة الرأسية عكسيا مع قاعدة العين