Saturday, August 30, 2008

Helicopter vs Airplane Aerials

Aerial photographs can be taken from either airplanes or helicopters. Helicopter aerials will incur an extra charge due to the extra expense, but sometimes it can be well worth the extra charge.

Close-up Details

Where the difference is especially noticed is in close-up detail photographs. With the helicopter, you are closer to the ground and closer to the site. For an airplane, you need a higher zoom factor for the same picture. The higher zoom factor will create a picture which is not quite as sharp, and for real tight close-ups, the needed zoom factor may not even be possible.

Example 1
Below are a pictures we took to show workers at a site making precast concrete pieces.

This is the picture from an airplane (210mm focal length). The workers and site are hard to pinpoint. The precast factory site is in the middle of the photograph.


Precast block construction

This is the picture from a helicopter with a less zoom factor (165mm focal length). Less zoom is needed since we were closer and lower:

Precast block construction
When we crop and enlarge the worker near the middle of the picture, we get the image below.

Precast worker
This close-up image would not be possible to get from an airplane.


Example 2

Below is a picture of construction from an airplane (150 mm focal length):

Pepsi Center aerial from plane

Here is a picture of the same construction from a helicopter with less zoom than the airplane (105mm focal length). Once again, less zoom is needed since we were closer and lower to the site.

Pepsi Center aerial from plane

Here is a cropped picture from the helicopter of some workers in the above picture. Uncropped picture source was 300mm focal length in a helicopter:

Pepsi Center aerial from plane



When an Airplane is sufficient

For large sites that you do not intend to zoom into, the difference can be minimal. Here is a picture taken from a plane and then one from a helicopter.

Photo from an airplane:


Pepsi Center aerial from plane


Photo from a helicopter: Pepsi Center aerial from helicopter

The two pictures are taken on two different days with different lighting, but the overall composure is similar. If details on the building are not needed, the helicopter might not be needed.

Metropolitan Areas

In some city areas with lots of buildings, it can be easier to get photographs in a helicopter. Due to the slower speed of helicopters, they are allowed to get closer to other buildings and be closer to the ground. If the site is surrounded by other tall buildings, it may be important to use a helicopter.

Site and Situation Dependent

Every site and job is different. We will work with you to obtain the best aerial images possible. Give us a call, and we can discuss if using a helicopter is right for you.


Till next time,
Debbie Cruikshank: debbie@coloradoaerial.com
Brian Cruikshank: brian@coloradoaerial.com
Colorado Aerial Photography, LLC

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Nathan Marcucci said...
This comment has been removed by the author.
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