Can someone explain how this pic was taken?
Join Date: Apr 2002
Location: Cheltenham
Posts: 143
Likes: 0
Received 0 Likes
on
0 Posts
Forget lense lengths, picture quality, hand shake etc , it a simple fake which can be demonstrated by scribbling on a pice of paper. Its simply down to perspective which is NOT compromised by shutter speed, film quality etc.The comparison AV8 boy did bears this one out of a comparison of how it should have looked.The runway lines are very almost parallel.Why arent the eliptical markings very close to the side of the runway nearly circular?( assuming they are circles of course). Funny how the elipses are the same in each photo...
Take a piece of paper, draw 2 long parallel lines and draw some circles down the side.........view from 80 or so degrees and you will NOT see the sort of eliplical distortion as displayed on the fake photos.The perspective has been selectively changed.
This photograph implies LAX is flat but the runway has a down gradient of 40 deg or so...
I'd say the photo JMC man highlights is an original. We are off to the left of the runway therefore you dont get such a tendency for the runway edges to converge. The aircraft is more af a planform than a head on view as before.
Take a piece of paper, draw 2 long parallel lines and draw some circles down the side.........view from 80 or so degrees and you will NOT see the sort of eliplical distortion as displayed on the fake photos.The perspective has been selectively changed.
This photograph implies LAX is flat but the runway has a down gradient of 40 deg or so...
I'd say the photo JMC man highlights is an original. We are off to the left of the runway therefore you dont get such a tendency for the runway edges to converge. The aircraft is more af a planform than a head on view as before.
Last edited by simon brown; 22nd Aug 2004 at 11:02.
Join Date: Aug 2000
Location: UK
Posts: 1,914
Likes: 0
Received 0 Likes
on
0 Posts
Excellent analysis AV8- it was obvious extensive use of distortion was made by Photoshop, so what this photographer has produced is not a 'picture', but a distorted work of art not belonging in Airliners.net. Unlike architects who try and correct for distortion to make things look like they should in real life, he intentionally distorted one of his pictures to produce 'artwork'.
SB, the 'ellipses', I assume you mean curved runway/taxiway edges only underwent a tiny bit of expansion/compression depending on height from the bottom of the picture, so there would not be much change in shape. I think tghe picture is a genuine photograph unfortunately spoilt by the photographer himself. There is a VFR lane to the west of LAX as far as I remember- the 747 would have a pitch angle of 10-15 degrees. From the quality of the picture it would seem to be a high strength good quality telephoto picture undergoing extreme distortion.
SB, the 'ellipses', I assume you mean curved runway/taxiway edges only underwent a tiny bit of expansion/compression depending on height from the bottom of the picture, so there would not be much change in shape. I think tghe picture is a genuine photograph unfortunately spoilt by the photographer himself. There is a VFR lane to the west of LAX as far as I remember- the 747 would have a pitch angle of 10-15 degrees. From the quality of the picture it would seem to be a high strength good quality telephoto picture undergoing extreme distortion.
Join Date: Apr 2002
Location: Cheltenham
Posts: 143
Likes: 0
Received 0 Likes
on
0 Posts
There was some distortion of the taxi way markings agreed , but not enough to imply differences between 30 deg and 80 deg..Try it draw a circle and view it from different angles. That image was not captured on his film in his camera. Its interesting that people immediately commented on the subject matter, ie a " Whats a 747 doing at that angle of climb".Had it been a photograph of an F15, no one would have questioned the dodgy perspective and this thread would have been quite short, because we all know F15s are capable of climbing out at these sorts of angles.
Its preying on what is being shown and what ones actual experiences/perceptions are, ie 747s dont climb at that angle.
This is how all optical illusions work to a certain extent.
Its preying on what is being shown and what ones actual experiences/perceptions are, ie 747s dont climb at that angle.
This is how all optical illusions work to a certain extent.
Join Date: Sep 2000
Location: SE England
Posts: 275
Likes: 0
Received 0 Likes
on
0 Posts
SB sez;
"Its simply down to perspective which is NOT compromised by shutter speed, film quality etc"
"Try it draw a circle and view it from different angles. That image was not captured on his film in his camera"
You make the mistake of assuming the camera sees what the human eye sees, and it most definitely does not. You cannot recreate the perspective of a photograph by merely drawing lines on a piece of paper and viewing them at different angles.
Without getting into the fake/real argument;
Long telephoto lenses distort one thing above all others and that is perspective. They foreshorten the image and make near and distant objects appear much closer together. A 400mm lens might make things appear 12X bigger, but they also make near and distant objects appear 12 times closer together - if we could see all the LAX runway in the photo then the foreshortening would trick our eyes and brain into thinking it wasn't 12,000 ft. long but a mere 1000 ft, although our knowledge tends to override the urge to fall for this illusion if we have the 'whole picture' as it were.
Try to ignore the background in the picture for a second, and just look at the aircraft. It is heading straight for the camera and without the background you have absolutely no idea how high the nose is, the only thing that gives you any clue whatsoever to the nose up angle is the background, but remember, you are seeing a heavily distorted background due to the foreshortening of the long lens, and it is this that makes it seem much more nose up than it is in reality. The section of runway visible in the photo might be 1000 ft long, but it 'appears' to be less than 100 ft. long due to the distorted perspective. Your brain subconsciously does the trigonometry and arrives at an estimate for the nose up angle, but it's making that calculation on seriously flawed data.
If we do the real trigonometry we can work out how much your brain is being deceived by. A bit of basic trigonometry gives you the 'apparent' nose up angle if you reduce the 'apparent' horizontal distance by a factor of 12, and it has a huge effect - i.e. a 10 degree nose up angle suddenly becomes an 65 degree apparent nose up angle [from opposite/adjacent = tan]. In reality the effect will be slightly less pronounced because the vertical distances are distorted too, albeit to a lesser extent, but I find it quite believable that a long lens could make 10° look more like 60 or so.
"Its simply down to perspective which is NOT compromised by shutter speed, film quality etc"
"Try it draw a circle and view it from different angles. That image was not captured on his film in his camera"
You make the mistake of assuming the camera sees what the human eye sees, and it most definitely does not. You cannot recreate the perspective of a photograph by merely drawing lines on a piece of paper and viewing them at different angles.
Without getting into the fake/real argument;
Long telephoto lenses distort one thing above all others and that is perspective. They foreshorten the image and make near and distant objects appear much closer together. A 400mm lens might make things appear 12X bigger, but they also make near and distant objects appear 12 times closer together - if we could see all the LAX runway in the photo then the foreshortening would trick our eyes and brain into thinking it wasn't 12,000 ft. long but a mere 1000 ft, although our knowledge tends to override the urge to fall for this illusion if we have the 'whole picture' as it were.
Try to ignore the background in the picture for a second, and just look at the aircraft. It is heading straight for the camera and without the background you have absolutely no idea how high the nose is, the only thing that gives you any clue whatsoever to the nose up angle is the background, but remember, you are seeing a heavily distorted background due to the foreshortening of the long lens, and it is this that makes it seem much more nose up than it is in reality. The section of runway visible in the photo might be 1000 ft long, but it 'appears' to be less than 100 ft. long due to the distorted perspective. Your brain subconsciously does the trigonometry and arrives at an estimate for the nose up angle, but it's making that calculation on seriously flawed data.
If we do the real trigonometry we can work out how much your brain is being deceived by. A bit of basic trigonometry gives you the 'apparent' nose up angle if you reduce the 'apparent' horizontal distance by a factor of 12, and it has a huge effect - i.e. a 10 degree nose up angle suddenly becomes an 65 degree apparent nose up angle [from opposite/adjacent = tan]. In reality the effect will be slightly less pronounced because the vertical distances are distorted too, albeit to a lesser extent, but I find it quite believable that a long lens could make 10° look more like 60 or so.
Last edited by Smoketoomuch; 22nd Aug 2004 at 15:30.
Join Date: Aug 2000
Location: UK
Posts: 1,914
Likes: 0
Received 0 Likes
on
0 Posts
However you look at it, the red bars in the picture by AV8boy show that some impossible perspective is involved. No amount of foreshortening in a telephoto can actually make the runway further away wider than nearer, as the red bars show. He has overcooked his perspective adjustment in Photoshop! It is therefore a 'fake' picture!
Join Date: Apr 2002
Location: Cheltenham
Posts: 143
Likes: 0
Received 0 Likes
on
0 Posts
Thats as it may be smokey, but how do you account for what appears to be selective distortion. If viewed from almost 80 deg above those circles should be almost circlular and not elipses indicating a narrower angle. I cant believe a lense is capable of this sort of distortion of a selective basis by paralleling up the runway as if from above but ignoring the other markings.If you look at the runway edge it looks a bit bold and contrived to me as well
"You cannot recreate the perspective of a photograph by merely drawing lines on a piece of paper and viewing them at different angles."
Of course you can .What do you think LAX is when viewed from above. A series of lines and circles.....same principles of perspective apply
I agree with Not so ..Its been fiddled with
"You cannot recreate the perspective of a photograph by merely drawing lines on a piece of paper and viewing them at different angles."
Of course you can .What do you think LAX is when viewed from above. A series of lines and circles.....same principles of perspective apply
I agree with Not so ..Its been fiddled with
Join Date: Sep 2000
Location: SE England
Posts: 275
Likes: 0
Received 0 Likes
on
0 Posts
Notso sez;
"No amount of foreshortening in a telephoto can actually make the runway further away wider than nearer, as the red bars show"
Err, unless I'm mistaken (which is perfectly possible after staring at the damn thing for so long) the red bars show the runway to be wider at the bottom of the photo than they are at the top? i.e. the perspective is not impossible. A very rough measurement on my screen shows the runway to be about 10% wider at the bottom than the top
SB sez'
"those circles should be almost circlular"
Don't know about that, I'm limiting myself to trying to explain the apparent nose up angle, and use of a long lens could easily explain it.
"Of course you can .What do you think LAX is when viewed from above. A series of lines and circles.....same principles of perspective apply"
Indeed, but they look very different when viewed through different lenses, i.e. human eye versus telephoto.
I'm not saying the picture is genuine or fake, just that its major apparent anomaly is explainable.
"No amount of foreshortening in a telephoto can actually make the runway further away wider than nearer, as the red bars show"
Err, unless I'm mistaken (which is perfectly possible after staring at the damn thing for so long) the red bars show the runway to be wider at the bottom of the photo than they are at the top? i.e. the perspective is not impossible. A very rough measurement on my screen shows the runway to be about 10% wider at the bottom than the top
SB sez'
"those circles should be almost circlular"
Don't know about that, I'm limiting myself to trying to explain the apparent nose up angle, and use of a long lens could easily explain it.
"Of course you can .What do you think LAX is when viewed from above. A series of lines and circles.....same principles of perspective apply"
Indeed, but they look very different when viewed through different lenses, i.e. human eye versus telephoto.
I'm not saying the picture is genuine or fake, just that its major apparent anomaly is explainable.
Join Date: Oct 2003
Location: Hampshire, UK
Posts: 207
Likes: 0
Received 0 Likes
on
0 Posts
boys boys boys...
These pictures have become increasingly trendy from LAX recently. This isn't the first - a few have done it. Light aircraft in the corridor over LAX, and lucky timing.
It's not faked.
It's not faked.
Notso wrote...
Err...haven't you misread AV8boy's post. Didn't he conclude in the end that although the runway looked wider at the top of the photo it is actually wider at the bottom of the photo. That's what the equal length red lines show.
However you look at it, the red bars in the picture by AV8boy show that some impossible perspective is involved. No amount of foreshortening in a telephoto can actually make the runway further away wider than nearer, as the red bars show. He has overcooked his perspective adjustment in Photoshop! It is therefore a 'fake' picture!
Join Date: Jan 2004
Location: LPPT
Age: 58
Posts: 431
Likes: 0
Received 0 Likes
on
0 Posts
There are only 2 ways of looking at this picture:
- It has been "worked", and if so, this discussion on "How this picture was taken" is useless, period.
-It's real, and if so, it’s possible and feasible to do it again.
Relying on this last assumption, and given the equipment that was said to have been used, a Nikon D100, I say again that was a smart way of taking advantage of a lens distortion error. The D100 is a digital camera capable of using normal/old film camera lenses, and with its 6 megapix CCD, the picture quality is very good, almost as good as its film equivalent (the Nikon F80) with the same lens attached. It can take pictures at a max shutter speed of 1/4000 sec's, more than sufficient to freeze any high speed movement. It’s capable of predicting the focus adjustment, due to object's movement, in a split second. It can calculate the necessary diaphragm aperture, based on the lens type, shutter speed and light measured on a 5 zone sensor across the picture area. Its one very "smart" machine that even knows which way is up. But it surely can't correct telephoto lens edge distortion problems. And if it’s a zoom type lens, the distortion problem is even greater, with distorted colors as well.
So IMHO, this is clearly a case of someone who knows he's equipment limitations/possibilities, and takes all advantage of this knowledge to produce an excellent eye-catching picture.
GD&L
- It has been "worked", and if so, this discussion on "How this picture was taken" is useless, period.
-It's real, and if so, it’s possible and feasible to do it again.
Relying on this last assumption, and given the equipment that was said to have been used, a Nikon D100, I say again that was a smart way of taking advantage of a lens distortion error. The D100 is a digital camera capable of using normal/old film camera lenses, and with its 6 megapix CCD, the picture quality is very good, almost as good as its film equivalent (the Nikon F80) with the same lens attached. It can take pictures at a max shutter speed of 1/4000 sec's, more than sufficient to freeze any high speed movement. It’s capable of predicting the focus adjustment, due to object's movement, in a split second. It can calculate the necessary diaphragm aperture, based on the lens type, shutter speed and light measured on a 5 zone sensor across the picture area. Its one very "smart" machine that even knows which way is up. But it surely can't correct telephoto lens edge distortion problems. And if it’s a zoom type lens, the distortion problem is even greater, with distorted colors as well.
So IMHO, this is clearly a case of someone who knows he's equipment limitations/possibilities, and takes all advantage of this knowledge to produce an excellent eye-catching picture.
GD&L
Join Date: Jul 2002
Location: California USA
Posts: 719
Likes: 0
Received 0 Likes
on
0 Posts
Didn't he conclude in the end that although the runway looked wider at the top of the photo it is actually wider at the bottom of the photo. That's what the equal length red lines show.
I do, however, stand firm in my desire to KNOW that the photo is real, and to gain a full understanding of why it looks the way it does. I didn't spend all that time with the image because I wanted to debunk it. Whether or not I came across as doing-so, I really did give the poster the benefit of the doubt. Having done that, I simply wanted to understand it. I am thankful that this discussion is fleshing-out the subject.
Of course, WANTING the danged thing to be "real" doesn't make it so.
I'd also hasten to add that photographers should not become defensive on the basis of this discussion. The question here remains limited to this one photo. Is it real, and if so, why does it look that way? Draw me a picture. Let's hear more about the altitude of the photographer, the angle of the shot, the geography of the airport, and why the equipment made the image look this way.
Join Date: Oct 2003
Location: Hampshire, UK
Posts: 207
Likes: 0
Received 0 Likes
on
0 Posts
The image was taken with a Canon D60 (digital SLR) with a 100-400 L IS lens. The lens is image stabilised, that is, one of the lens groups is gyro-stabilised to minimise the effect of camera shake. Aperture was 7.1 shutter speed 1/640sec and focal length was at 400mm. Continuous drive was used (click-click-click) so it's likely it will have been the best of several frames.
Yes it was a shoreside flyby.
Discussion thread is here:
http://www.airliners.net/discussions...d.main/144989/
With regard to the aircraft pointing straight at the camera, don't forget that zoom lenses will distort distance. The 747 is probably much higher than it looks.
Cheers
James
Yes it was a shoreside flyby.
Discussion thread is here:
http://www.airliners.net/discussions...d.main/144989/
With regard to the aircraft pointing straight at the camera, don't forget that zoom lenses will distort distance. The 747 is probably much higher than it looks.
Cheers
James
Join Date: Sep 2003
Location: Retford, UK
Posts: 476
Likes: 0
Received 0 Likes
on
0 Posts
I'd note some points (great photo BTW):-
- I've flown this corridor in a Cessna 172 and it is a very nice route for sightseeing. Perfect timing for this shot though as there is no way you can circle until a heavy lifts off!
- because of the angle of attack during the initial high drag/lift phase of take-off, although it looks as though the 744 is headed straight for us, it's actually going to pass well under us.
- it must be an extremely long lens to remove all perspective foreshortening on the runway. The only thing I don't understand how the top of the runway can be wider than the bottom, it must be some effect of the lens optics at that focal length.
- Michael
- I've flown this corridor in a Cessna 172 and it is a very nice route for sightseeing. Perfect timing for this shot though as there is no way you can circle until a heavy lifts off!
- because of the angle of attack during the initial high drag/lift phase of take-off, although it looks as though the 744 is headed straight for us, it's actually going to pass well under us.
- it must be an extremely long lens to remove all perspective foreshortening on the runway. The only thing I don't understand how the top of the runway can be wider than the bottom, it must be some effect of the lens optics at that focal length.
- Michael
Join Date: May 2002
Location: Cheshire, UK
Age: 61
Posts: 173
Likes: 0
Received 0 Likes
on
0 Posts
The only thing I don't understand how the top of the runway can be wider than the bottom, it must be some effect of the lens optics at that focal length.
JT
Join Date: Sep 2003
Location: Retford, UK
Posts: 476
Likes: 0
Received 0 Likes
on
0 Posts
It isn't. It just looks wider. See post about 2 pages ago with the red lines on it.
http://www.webdeveloper.com/design/images/illusions.gif
- Michael
Join Date: Aug 2002
Location: Southern England
Posts: 119
Likes: 0
Received 0 Likes
on
0 Posts
Don't know how I quite ended up here...
But this had me intrigued. So I thought a quick way to see if its just down to the telephoto lens is to try it on MS FS200x. Setup the t/o paused at the right point after wheels off and moved the spotter a/c to the right place and BINGO. Worked like a dream.
On zoom in I've recreated the picture, on zoom-out everything looks normal (and angle of rotation of the 744 is normal - approx 10-12 degrees)
Now I can take some screen shots to show this, but don't have the webspace to host them (or then know how to get them on here) so if anyone is still bothered pm me and I send them to you.
PS I was lucky enough to rent & fly round the Socal area a couple of years ago, including over LAX - the views are truly fantastic
But this had me intrigued. So I thought a quick way to see if its just down to the telephoto lens is to try it on MS FS200x. Setup the t/o paused at the right point after wheels off and moved the spotter a/c to the right place and BINGO. Worked like a dream.
On zoom in I've recreated the picture, on zoom-out everything looks normal (and angle of rotation of the 744 is normal - approx 10-12 degrees)
Now I can take some screen shots to show this, but don't have the webspace to host them (or then know how to get them on here) so if anyone is still bothered pm me and I send them to you.
PS I was lucky enough to rent & fly round the Socal area a couple of years ago, including over LAX - the views are truly fantastic
Join Date: Jul 2002
Location: California USA
Posts: 719
Likes: 0
Received 0 Likes
on
0 Posts
Here are the pics to which down&out referred. I wish I could take credit for them, but, of course, I can't! I'm a little miffed that it never occurred to me to try this in FS... Nicely done!
I'll let down&out explain. I've numbered the shots in the same way he did for reference...
Slide 1:
Slide 2:
Slide 3:
Dave
Nicely done!I'll let down&out explain. I've numbered the shots in the same way he did for reference...
Slide 1:
Slide 2:
Slide 3:
Dave