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FAQ (Frequently asked Ouestions)

QUESTION: Adrian from the UK was asking why using APDER and its equipment to take Aerial Photos when there are so many helicopters flying around in situations like the earthquake in Haiti or the Tsunami in Japan?
APDER ANSWER: There are several reasons to deploy APDER
1. Not in all situations helicopter are available for instance if in remote location such as a flooding in Benin or an  earthquake in the mountains of Pakistan
2. During a disaster especially in the first days the helicopters are mostly deployed for rescue and evacuation purposes - it would be difficult for every decision maker to justify to the public why the helicopters are deployed to make aerial photos even if it would serve to save more lives.
3. The quality of APDER images is quite good and it is difficult to match the same results with photos from a helicopter or a small plane considering the vibration of the engines.
4. Urban Search & Rescue (USAR) teams can use the photos immediately on the ground in order to determine where to search and therefore to save important time to save human lives especially after flooding and earthquakes.
5. At the end of the day it is also a question of money- an helicopter costs up to several thousand USD per flying hour.

QUESTION: What is the difference between Aerial Photos and Maps?
Aerial photographs are NOT maps, although both maps and aerial photos present a "bird's-eye" view of the earth. Aerial photos display a high degree of radial distortion. That is, the topography is distorted, and until corrections are made for the distortion, measurements made from a photograph are not accurate. Because most GISs can correct for radial distortion, aerial photographs are an excellent data source for many types of projects, especially those that require spatial data from the same location at periodic intervals over a certain length of time. Maps can be actualized through data acquisition by satellite images, aerial photographs or other means. The data is processed and displayed on a map hence a map can contain information which one can not see as for instance names of Roads and Towns, Risk Factors, Vulnerability Factors etc.

QUESTION: What is the advantage of Aerial Photos compared with maps?
Map production requires time and is costly. In sudden on-set disasters time is one of the most important factors to save life. In catastrophes and hazards the situation changes very rapidly, sometimes even within minutes. Information provided by maps are usually not up to date. The production of maps needs time. Aerial photos can be used and analysed immediately, reflecting the actual changes.
Nevertheless, aerial photographs are a powerful tool for studying the earth's environment or they can directly be used in disasters in the first phase of the response, for instance supporting On-site Coordination or USAR (Urban Search and Rescue) teams in cases of earthquakes, tsunamis and flooding. Also Aerial Photos are sufficient for the purpose of planning and coordination in the disaster response as they can provide ideas about numbers and location of affected population, proportion of damages etc.

QUESTION: What is the difference between APDER and Organisations who do mapping?
We as APDER producing Aerial Photos meaning we acquire data which can be processed by NGOs specialised in mapping such as CARTONG or MAP Action or any other GIS-United of an Organisation engaged in Civil Protection, Humanitarian Action, Development Cooperation, Protection of the Environment etc.

QUESTION: Why do we need Aerial Photos in Disasters when there are Satellite Images available?

1. Production of Satelitte Images is very expensive. If the International Space Charter (see: Devices to capture Imagery) is activated the provision of satellite images is free. However not anybody can activate the Space Charter with the consequence that especially disasters or hazards with a smaller geographical impact are not covered.
2. The charter does not oblige members to deliver Satellite Images. Some members of the Space Charter are private providers and their willingness to provide might be on stage at a certain time in the future.
3. For those members who are financed by the public hand the question can be posed - where comes the money from?. There are indications that this money is and will be provided through the different ministerial channels within a government. Consequently the payment of Satelitte Photos derives from the budget earmarked for Humanitarian Action and Development Cooperation. Satellite Images compared with Aerial Photos are expensive (up to 30 - 40 000 USD for a processed photo) and the Humanitarian Aid and Development Cooperation Communitty should reflect on that.
4. The quality (Resolution) of Satelitte Images is lower than Aerial Photos. Depending on the type of disaster this can be a handicap.
5. Normally Satellite images are produced vertical (bird`s eye view) which does not provide an 3 Dimensional idea of the disaster zone. In some disaster situation 3 D impression is very important. (Remark: Technically with some Satellites it is possible to produce images with anther angle but it seems to costly to redirect Satellite and camera.) 
6. In the early stages of a Disaster it can occur that the transmission of Satellite images from Satellite provider to the zone of the disaster (Onsite Operation and Coordination Centre or even the National Crises Centre) is impossible because of the tremendous increase of communication traffic and the limited band width of Satelite connection or even the destroyed communication infra-structure of the concerned disaster zone or region.