Calculating Resolution at Altitude - Rugged Video - Airborne Video Systems

A question we often get at Rugged Video is “How far away will the camera capture?”  .  The answer is “It’s complicated”  which isn’t a very helpful answer;  That is why we decided to tackle the issue once and for all in a blog post.  If you are looking to start aerial patrol work or looking add capabilities to your operation this resource will be helpful in understanding what to expect from a camera solution.  This could also be a good reference for aerial photography, survey, and aerial mapping applications.

For more information on geospatial recorders and high definition camera options click the links below:

Geospatial Video Recorders

HD Aircraft Cameras

 

What determines how far the camera captures?

All Rugged Video cameras are shipped focused on infinity, or the horizon.  The cameras offer a wide depth of focus which means everything between about a foot in front of the camera, out to the horizon will appear in-focus.  The main issue at hand is how detailed an object will be that is say 500ft below your aircraft, this doesn’t have to do with focus, but you do need to know your resolution density.

How do you find the resolution density?

The resolution density will be measured in pixels per sqft.  To calculate the resolution density we need: the camera resolution, the camera field of view, and your altitude above ground level.   Once the resolution is calculated we can approximate how well we will see an object.  Resolution density is the number of pixels that will make up a square foot of an image.

 

Whats my resolution density?

The chart below will help you find your resolution density of a 1080p camera (1920×1080 resolution) with the listed FOV and altitude.

Calculating Resolution at Altitude (In Pixels/Foot)
Resolution = 1920 Feet Above Ground Level
FOV in Degrees 100 250 500 1000 2000 3000
10 12040.3 1926.5 481.6 120.4 30.1 13.4
15 5317.2 850.8 212.7 53.2 13.3 5.9
20 2964.2 474.3 118.6 29.6 7.4 3.3
25 1875.1 300.0 75.0 18.8 4.7 2.1
30 1283.6 205.4 51.3 12.8 3.2 1.4
35 927.0 148.3 37.1 9.3 2.3 1.0
40 695.7 111.3 27.8 7.0 1.7 0.8
45 537.1 85.9 21.5 5.4 1.3 0.6
50 423.8 67.8 17.0 4.2 1.1 0.5
55 340.1 54.4 13.6 3.4 0.9 0.4
60 276.5 44.2 11.1 2.8 0.7 0.3
65 227.1 36.3 9.1 2.3 0.6 0.3
70 188.0 30.1 7.5 1.9 0.5 0.2
75 156.5 25.0 6.3 1.6 0.4 0.2
80 130.9 20.9 5.2 1.3 0.3 0.1
85 109.8 17.6 4.4 1.1 0.3 0.1
90 92.2 14.7 3.7 0.9 0.2 0.1
95 77.4 12.4 3.1 0.8 0.2 0.1
100 64.9 10.4 2.6 0.6 0.2 0.1
105 54.3 8.7 2.2 0.5 0.1 0.1
110 45.2 7.2 1.8 0.5 0.1 0.1
115 37.4 6.0 1.5 0.4 0.1 0.0
120 30.7 4.9 1.2 0.3 0.1 0.0
125 25.0 4.0 1.0 0.2 0.1 0.0
130 20.0 3.2 0.8 0.2 0.1 0.0
135 15.8 2.5 0.6 0.2 0.0 0.0
140 12.2 2.0 0.5 0.1 0.0 0.0
145 9.2 1.5 0.4 0.1 0.0 0.0
150 6.6 1.1 0.3 0.1 0.0 0.0
155 4.5 0.7 0.2 0.0 0.0 0.0

 

What does this number really mean?

Its hard to get an idea of what this relates to in actual picture quality.  To help we’ve attached a few examples below.  You have to click the image to view in its full resolution density.

Pixel Density = 155 Pixels per square foot.   Click to View at 155 PD

Resolution Density = 155 Pixels per square foot.
Click to View at 155 PD

 

Rugged Video Camera Resolution at Altitude

Resolution Density = 100 Pixels per foot
Click to View at 100PD

Rugged Video Camera Resolution at Altitude

Resolution Density = 70 Pixels per square foot
Click to View at 70PD

Rugged Video Camera Resolution at Altitude

Resolution Density = 50 Pixels per square foot
Click to View at 50PD

Rugged Video Camera Resolution at Altitude

Resolution Density = 36 Pixels per square foot
Click to View at 36PD

Rugged Video Camera Resolution at Altitude

Resolution Density = 25 Pixels per square foot
Click to View at 25PD

Rugged Video Camera Resolution at Altitude

Resolution Density = 16 Pixels per square foot
Click to View at 16PD

Rugged Video Camera Resolution at Altitude

Resolution Density = 9 Pixels per square foot
Click to View at 9PD

I know what I am looking for, now what?

We can help you find the airborne cameras and HD recorder that best meets your needs.  Click the contact us option or give us a call at (414) 399-3370 and our airborne video experts will be happy to help you with any questions.