Not All Pixels Are Equal

Pixels... a term that originated from the phrase "picture elements."

Recently I decided to look closer at the images generated by the various cameras I've been using for my aerial/drone-based still photography. And when I say look closer, I'm speaking of zooming in on any given image so that each pixel of the computer monitor represents each pixel of the digital photo. In Adobe Photoshop that is considered viewing at 100%. I think you'll be surprised at the results posted below. Although every image isn't from the same location, I think you'll find in these samples that a higher resolution count doesn't always mean a better quality image.

This is from the Xiaomi Mi 14MP sports camera.

This is from the Phantom 3 Advanced 12MP camera.

Keep in mind, these images are all being presented at a 1:1 pixel ratio. So even the higher resolution cameras are being judged at the same pixel level as the lower resolution offerings.

This is from the 8MP Syma sports camera that comes with the X8HG.

This is a generic 5MP GoPro-like sports cam that cost about $33 from Amazon.

This image is from the modestly priced JJRC H-12 that comes with a 5MP pinhole-type camera.

Note the difference between these last two cameras that have the same resolution. I think I would even prefer the 5MP JJRC H-12 camera over the Syma 8MP offering. But things really get interesting now...

Here is an image from the 3.8 MP RunCam 1. That's pretty sweet!

And here is the RunCam's cousin, the 3.6MP Mobius camera.

And finally the 808 #16 Keychain camera weighing in at 1.2MP.

As you can clearly see in these samples, not all cameras are the same when it comes to generating pixels. There's likely several reasons why more isn't always better. Some of the factors include factory compression settings, sensor quality, and the type of sensor.

Lastly, if you're wondering about attaching your smart phone to your UAV, have a look at this…

8MP iPHone 6.

Miniaturize It

Syma X8C with Mobius camera on board. Processed in ON 1 Photo 10.

Miniaturizing an aerial image can be an easy and powerful process. By reducing the depth of field, an image taken from an elevated view can be transformed. If you have Photoshop, it's pretty easy: 

   -Select the area that you want to remain in focus.
   -Feather the selection. The higher the resolution of your image, the more feathering required.
   -Inverse the selection.
   -Apply a blurring filter such as the Gaussian blur. Experiment with the amounts

There are other photo editing applications out there that offer "lens blurring" effects that make this an even easier task to accomplish. I typically use ON1 Photo10 or (if on my smart phone) Snapseed. 

Cold-Weather Flight

Syma X8C with a Mobius camera between Deaver and Powell, Wyoming on a sub-zero winter morning. Edited in On1 Photo 10 software.

The first time it happened, I had a 42% battery charge on my Phantom 3. It was mid-autumn, but a cold morning coming from Ten Sleep up the Nowood Road. Earlier in the trip I had just passed over the frosty heights of the Big Horn Mountains. The Phantom (or at least its battery) was in the back of the truck instead of riding up front with me. I pulled over the side of the road and prepared to make a short flight over a colorful area of badlands. I checked the battery charge again to confirm I had enough juice for the brief flight. The aircraft was up and away quickly, and over a power line that paralleled the highway.

A little more than 100 yards out, I hear the robotic voice of the controller warning me that the battery is critically low. It immediately loses altitude not far beyond the power line and the craft becomes sluggish in responding to my commands. The terrain below the drone is rough, and if it forces a landing, I'll surely lose a prop or two. At about fifteen feet off the ground it seems to stabilize and slowly works its way back under my command. I make a catch landing and instantly begin thinking about what went wrong.

It doesn't take too long before I consider the coldness of the battery while it was riding in the back of the truck. Another lesson learned without serious consequences.

Today I took my Syma X8C out on a morning that was -12°F. Given these temperatures, the cab of my truck even has a hard time staying warm. Nevertheless, I kept too fully charged batteries in the breast pocket of my coat and close to my body. When I arrived at the flight area, I installed one of batteries into the quadcopter within the confines of my truck, and had it flying shortly after.

It was a great flight in terms of the aircraft's performance—it could have been any other day. But, after 8 minutes of standing in the sub-zero conditions, it was I who was suffering from the cold this time—not my battery.