Question 2. Photo taken from plane. What are these strange lines ?

Question

The photos were taken on Sunday. These lines kept showing up in a whole lot of the photographs. And we can't work out what is causing them. The propeller is in front of the white bit , and I guess the odds are that it's causing it somehow.

I thought it was an interesting thing whatever it is.

http://www.flickr.com/photos/16949082@N07/2262866350/in/photostream/

Do you have any suggestions about what is causing this ?

Answer 1

prop effect perhaps a polarizer may not have helped it may have helped it dunno.

Answer 2

Is it a heated windshield?  Does it have very fine horizontal heating filaments?

Answer 3

It's not the prop.  The lines extend past the front of the cowling toward the cockpit, and they're horizontal, where any prop lines would be curved.

I think it's something in the windscreen itself (heating element), or a reflection off the top of the cockpit coaming.

Answer 4

It looks like a reflection, either on your camera lens or on the window. If it were from the prop, I don't think you'd see the lines on the black part of the engine nacelle.

Answer 5

Lizzie,

When you're taking pictures through the prop, slow your shutter speed down a bit and this wont happen. It looks like prop capture, the only way I know this is that one of the lines in the shot has the reflection of light on the upper edge, what puzzles me is that the lines are all the same distance from each other which is kinda wierd, they should be at an angle from the center of the rotor shaft which suggests that you must have hit a bit of turbulance.  the faster your shutter, the more prop you'll see in the shots you take, ....so I'd suggest a shuuter speed of 60 or 125, the lower the better and your f stop up near 11 or even 16......thats all I know to tell you to try. if these shots arent of the prop, they could be ( possibly ) shock waves from prop wash but that's unlikely, not impossible but unlikely.

Answer 6

i never tried taking one through the front of the plane, maybe next time i go up i will just to see if i get the same effect. it could be the prop i suppose.

Answer 7

The "white bit" is the cowling. Most props have relativley low RPM's. The redline is 2500 RPM for most aircraft. Your shutter propably is capturing the prop's rotation.

Answer 8

The only thing we all can think of is the PROP,  but that is not really a good explanation. A prop wouldnt create horizontal patterns like that. Its probably being reflected from something ABOVE the camera or above the camera lens.

Answer 9

Thats what propeller blades look like through a digital camera.  There is a little bit of lag inside the camera's electronics as it dumps photons from the CCD onto the memory stick.  What you are seeing is the result of that lag.

If you look into how a digital camera actually works it will make more sense.  Think of it as a series of buckets that catch photons.  Every so often, those buckets are emptied.  They move in a kind of conveyor belt back toward the memory stick, one bucket dumping into the next and into the next and so on.  this process happens very fast, but it is not instantaneous.  Fast-moving objects like propeller blades cause odd effects like what you are seeing.

Answer 10

Yes, it is the propeller.

It is a combination of shutter speed, shutter type, and propeller speed that creates this effect.

You can see a really weird YouTube video of a prop here that has the same sort of effect:

http://youtube.com/watch?v=2A05YWVW3Tw