Z8 distortion with airplane detection

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MattOZW

MattOZW

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Took a shot of this A380 for my son who flies these things whilst I was out birding, I changed to the airplane detection mode and these are the shots I got showing distortion of the tail section as the plane was approaching and the front section as it was going. Am I doing something wrong or is it the camera? Z8 with 500PF and 1.4 teleconverter, images attached f8, 1/2500s ISO 280
20240229-DSC_5629-Enhanced-NR.jpg
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20240229-DSC_5667.jpg
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Besides perhaps atmospherics making the images softer, everything else is as it should be:
First image: You were in Airplane mode. In that mode the camera will always focus on the cockpit, and that's what it did here. The tail end in that image is not distorted - it's less sharply focused due to lack of depth of field.
Second image: In airplane mode the camera cannot identify the cockpit since you were shooting the plane from behind. In that case the camera focused on the belly of the plane, leaving both front end and tail softer focused due to lack of depth of field.

When shooting animals from head-on and focusing on the eye, most folks are comfortable with the nose and the rest of the animal slightly softer due to lack of depth of field. The eyes are the most important and they have to be sharp. The same will be true for shooting airplanes. The cockpit where the pilots are has to be sharply focused.

The only thing you could do in this case is to select a smaller aperture to increase depth of field. That will bring the tail end into sharper focus in Image #1. You could do the same for image #2, but with the cockpit not identifiable for the camera it's a crap-shoot on where it will decide to focus. In that case you would do better to select a single point on the plane to focus and not allow the camera to pick the focus point.
 
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I took photos at an airshow last Summer. Heat from the engines and warm air rising from the ground often created sharpness-robbing heat plumes. Engine exhaust would explain the tail distortion in the first photo.

Also, f/8 indicates that your 500mm f/5.6 lens with 1.4x converter is being used wide open. Perhaps stopping the lens down by 1/3, 2/3, or 1 stop would help achieve greater sharpness and depth of field.
 
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I don't know this plane very well from memory.
But does not lenght "a" seems very large ?
And does perspective justify differences between lenght "b" and lenght "c" ?
What do you think ?

distortion.jpg
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if not, neither heat distortion, nor atmospheric distortion nor any physic parameter can justify that ?

If both op images show the same plane, there is something very strange in image 1, no ? At least for the tail (lenght "a").
 
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I think it may be partly an optical illusion. I think the belly of the plane tapers up toward the tail. Deceptive. I can see it both ways. I can see the section marked as "a" as width or I can see both ends of "a" in line with the center line of the plane's body.
 
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JoPoV said:
I don't know this plane very well from memory.
But does not lenght "a" seems very large ?
And does perspective justify differences between lenght "b" and lenght "c" ?
What do you think ?

View attachment 83326
if not, neither heat distortion, nor atmospheric distortion nor any physic parameter can justify that ?

If both op images show the same plane, there is something very strange in image 1, no ? At least for the tail (lenght "a").
Click to expand...


Looks as expected - viewer is perpendicular to "wing b" while "wing c" trails off at 45 degrees or more so "c" appears shorter than "b". And the belly tapers up to the tail causing "a" to look flat and wide.
 
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I didn't visualize the fuselage profile very well. It is indeed partly an optical illusion : both ends of "a" are in line with the center line of the plane's body and not perpendicular to the fuselage as I saw first.
No distortion so.
 
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I have spent most of my life photographing aeroplanes and I don't see any distortion in either of the images - looks fine to me (it is a Boeing 747 by the way!).
The only "distortion" that I can see is in the second image where the underside of the fuselage is almost the same colour/tone as the sky. If you enlarge the image you can just make out the contour of the fuselage against the sky, so it is just an optical illusion. Is this what the OP is referring to?

Alan
 
The only other possible cause would be rolling shutter, but on that camera it is not an issue, and even if it was, as it is on some cameras, the plane would be going too slow, as the wings are not flapping.

Perhaps perspective explains what is seen.
 
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bleirer said:
The only other possible cause would be rolling shutter, but on that camera it is not an issue, and even if it was, as it is on some cameras, the plane would be going too slow, as the wings are not flapping.

Perhaps perspective explains what is seen.
Click to expand...
They might have been flapping if the 747 was ever put into Boeing's MAX program! :rolleyes:

--Ken
 
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