Flight Test of E-5

On Thursday March 10^th, we took some test aerial images around Lawrence. We had several reasons for taking to the skies with the E-5: 

- What is the best focal length for our project?
- What is the best focal length, f-stop, and lens combination that will give us the best resolution for our project needs?
- Can we rely on Aperture Priority mode and what f-stop can we use without motion blur in our images?
- Production of test images so we can find which post-processing methods will be better for phase II projects.
- Getting a 'feel' for the effect of elevation on image resolution.
- Getting a qualitative 'feel' for what our images may look like when they are attached to the balloon.

Taking nadir looking photos from the window of an airplane moving around 100 mph was difficult. The wind was very strong and very cold. The articulating screen and digital level of the Olympus E-5 helped immensely by letting me hold the camera out the window, and while the camera is was facing downward, being able to see both the subject and at what the camera angle was.

Figure Vijay, our pilot Victor, and Ryan. Taken with an Olympus E-PL2.

Nadir-looking image of KU's experimental algae pool north of Lawrence. Taken with the E-5 and 12-60 Zuiko lens at 4500ft. Camera settings: 30mm f/3.6 1/3600 sec.

200% crop of previous picture. Each circular pool here is 3m in diameter.

Quail Run Elementary School in Lawrence. Taken with Olympus E-5 looking straight down. Camera Setting: 40mm f/3.8 1/2500 sec.

100% crop of previous photo. You can see the kids at recess.

Overall, we were impressed with how well the camera was able to resolve images, especially considering the conditions under which the photos were taken; handheld out the window of a fast moving airplane. We are still looking through the images. More to come. 

- ryan callihan - camera team

Image Footprint Calculations

We want to make sure that we have an appropriate focal length for capturing our area of interest. We’ve worked out some calculations of the camera’s image ‘footprint’ at various focal lengths and altitudes. Our likely focal length will be between 30-35mm. The graph above shows the footprint or coverage area at various altitudes with a 34mm focal length. There is a polynomial relationship between altitude and image footprint in meters². 

The equation for this relationship is: Y=0.1954x² + 1.0421x - 7149.7 

Y= footprint in meters² x= altitude in meters

For example, according to this relationship, at 20,000 meters in altitude, we will have a footprint of 78173692 meters² (or 30.18 miles squared).  This relationship was derived using a formula for angle of view ( theta = 2 arctan (d/2f), where f=focal length and d= size of focal plane) and then the formula for one dimensional swath width ( swath width = 2(H tan (theta/2)).

- ryan callihan - camera team

Box Assembly @ Lisa's

A VIEW FROM ABOVE

 rayleigh scattering

 what does the atmosphere do to known targets?

atmospheric haze issues 

remote sensing of a different kind

photos by ryan callihan

. . . . . . . . .

Yesterday, class went up to the top of Lindley Hall to discuss the atmospheric disturbances that will challenge the interpretation of our imagery.  The view to the south at first glance appeared to be quite clear. But, towards Clinton Lake the increasing "haze" was evident in successive hills to the south by southwest (between McCollum Hall and the southern ridge of the Wakarusa Valley). A photo was taken with our Olympus E-5 with a high horizon in an attempt to capture this effect. The photo was taken towards the sun. A water tower just a few miles south was also photographed.  It came out surprisingly well with a clear shadow opposing the sun.  A well-known large American Flag on 23rd street appeared faded in its color even at a modest distance.  Instructor Dobbs asked us to imagine a way we could simulate the column of air that our camera will experience with a comparative horizontal distance on the ground.   This could prove valuable for calibrating our data.

- robert anderson -

A Special Announcement from the PR Team

Project GeoHawk would like to thank Luhr Bros. Inc. for their generous donation to our project. This funding will allow us to expand our operation with additional component parts and building materials.  We are proud to be a new addition to their continued support of education and research. 

- kelly miller : pr team -