50mm "Normal" Lens... Ok, but "Normal" on FF or APS-C Sensor?

Started Nov 10, 2012 | Discussions
jon404 Senior Member • Posts: 2,152
Re: 50mm "Normal" Lens... Ok, but "Normal" on FF or APS-C Sensor?

>"But it's the change in shooting position that changes the perspective, not the change in focal length."

You have summed up this whole thread in one sentence. Excellent!

-- hide signature --

Jonathon Donahue -- Olympus XZ-1 tips at http://jon404.com

DenWil
DenWil Veteran Member • Posts: 3,077
Re: Not the 50mm myth again. That one is tough to kill!

They do say the more experienced a shooter you become...

.... the more wide-angle is the lens you're most comfortable with.

What a crock that is.

jvkelley Contributing Member • Posts: 849
A normal lens has about a 45 degree angle of view -From 1922 book.

I spent a few minutes on Google to try to find the oldest possible reference to a "normal" lens.  The oldest thing I could find was a book called "The Exhibition Print" published in 1922.  On page 367, the author refers to a normal lens having an angle of view of about 45 degrees.  This would be 52mm on a full frame camera.  This was published back when view cameras with various sized films were common.

After reading this, I'm starting to question all those articles and myth debunkers that say a normal lens is really wider than 50mm on full frame.

The Exhibition Print

-- hide signature --

J.V.

 jvkelley's gear list:jvkelley's gear list
Canon PowerShot S50 Canon EOS 400D Canon EOS 70D Canon EF 50mm f/1.8 II Canon EF-S 17-55mm f/2.8 IS USM +3 more
Barrie Davis
Barrie Davis Forum Pro • Posts: 21,460
Re: Not the 50mm myth again. That one is tough to kill!

DenWil wrote:

They do say the more experienced a shooter you become...

.... the more wide-angle is the lens you're most comfortable with.

What a crock that is.

You think so, huh!?

Well, all the old photographers I know say the same thing... professionals, and amatuers alike.

What's more, I can state from experience that women, as a group, prefer wide-angle lenses, (presumably so they can get a lot in!)...

... where young men like a nice L-O-N-G telephoto lens, (the longer the better, apparently!)

Pick the bones out of that!

-- hide signature --

Regards,
Baz
"Ahh... But the thing is, these guys were no ORDINARY time travellers!"

 Barrie Davis's gear list:Barrie Davis's gear list
Konica Minolta DiMAGE A2
Barrie Davis
Barrie Davis Forum Pro • Posts: 21,460
Re: Not the 50mm myth again. That one is tough to kill!

JulesJ wrote:

Barrie Davis wrote:

JulesJ wrote:

I sort of have to disagree with you here. If what you are seeing through your lens (and hence are photographing) is exactly the same as you see with your eyes, then I think that IS as standard as you can get.

Why? You do realise that the smaller the screen, the longer the lens you would choose after Size-match, don't you?

As you are fully aware, the rendering of perspective is the same for all f-lengths shooting from the same point is space....

.... so it doesn't matter which f-length happens to match your other eye's vision for SIZE as such... which will be different from one viewfinder system to another, or if you put on spectacles... (reading type glasses magnify AND reduce field of view.)

So, having dispensed with image SCALE as it appears through the viewfinder, all ELSE that varies as you zoom is Field of View... which, as I'm also sure you are aware, can't be pinned down in human vision, because it changes constantly depending on what you're looking at....

... like a room full of people scanned for the one you are there to meet, (wide angle)...

... or that very narrow section of road-width ahead that you are really REALLY concentrating on because you are flying towards it at 70mph. (telephoto)

And anyway, what if you are looking at a 3" LCD, or a waist-level finder as in a Rollieflex or Hasselblad, instead of an eyelevel finder?

Does the lens in use suddenly become NOT a 'normal' one because the viewfinding image as rendered on your retina is now vastly smaller than it was when the camera was pressed against your eye? I mean, viewfinder SIZE has changed hasn't it?

Indeed, its retinal size HAS changed, strictly because of viewfinding conditions, nothing else. The actual lens had no influence whatsoever.

It is a good job the viewfnder characteristic has nothing to do with what is, or is not, a normal lens.... otherwise photographic composition would be extremely confusing.

Matching the size and register between your viewfinder eye and the one looking directly past the camera is 10 seconds of mild amusement, and it would be fun if there was more to it in some way useful..

.... but it isn't, sadly

Ah I have to disagree with you here Barrie. The sensor size has nothing to do with what I am talking about. It is to do with distortion, compression of the image as in a wide angles shot and whatever the opposite is called with a long telephoto. The situation I describe is when there is neither compression or stretching (shall we call it)of the image. it is as natural as you you see it. As I said the sensor makes no difference, that would just vary the cropping of what you are photographing.

Hmmm... It is clear you haven't understood what I'm saying, which surpises me. It wasn't about sensor size but about viewfinder size. In fact, I didn't mention sensor size at all....[??]

Never mind.
I think it is best to drop it.
Best wishes.

-- hide signature --

Regards,
Baz
"Ahh... But the thing is, these guys were no ORDINARY time travellers!"

 Barrie Davis's gear list:Barrie Davis's gear list
Konica Minolta DiMAGE A2
JulesJ
JulesJ Forum Pro • Posts: 44,871
Re: Not the 50mm myth again. That one is tough to kill!

Barrie Davis wrote:

JulesJ wrote:

Barrie Davis wrote:

JulesJ wrote:

I sort of have to disagree with you here. If what you are seeing through your lens (and hence are photographing) is exactly the same as you see with your eyes, then I think that IS as standard as you can get.

Why? You do realise that the smaller the screen, the longer the lens you would choose after Size-match, don't you?

As you are fully aware, the rendering of perspective is the same for all f-lengths shooting from the same point is space....

.... so it doesn't matter which f-length happens to match your other eye's vision for SIZE as such... which will be different from one viewfinder system to another, or if you put on spectacles... (reading type glasses magnify AND reduce field of view.)

So, having dispensed with image SCALE as it appears through the viewfinder, all ELSE that varies as you zoom is Field of View... which, as I'm also sure you are aware, can't be pinned down in human vision, because it changes constantly depending on what you're looking at....

... like a room full of people scanned for the one you are there to meet, (wide angle)...

... or that very narrow section of road-width ahead that you are really REALLY concentrating on because you are flying towards it at 70mph. (telephoto)

And anyway, what if you are looking at a 3" LCD, or a waist-level finder as in a Rollieflex or Hasselblad, instead of an eyelevel finder?

Does the lens in use suddenly become NOT a 'normal' one because the viewfinding image as rendered on your retina is now vastly smaller than it was when the camera was pressed against your eye? I mean, viewfinder SIZE has changed hasn't it?

Indeed, its retinal size HAS changed, strictly because of viewfinding conditions, nothing else. The actual lens had no influence whatsoever.

It is a good job the viewfnder characteristic has nothing to do with what is, or is not, a normal lens.... otherwise photographic composition would be extremely confusing.

Matching the size and register between your viewfinder eye and the one looking directly past the camera is 10 seconds of mild amusement, and it would be fun if there was more to it in some way useful..

.... but it isn't, sadly

Ah I have to disagree with you here Barrie. The sensor size has nothing to do with what I am talking about. It is to do with distortion, compression of the image as in a wide angles shot and whatever the opposite is called with a long telephoto. The situation I describe is when there is neither compression or stretching (shall we call it)of the image. it is as natural as you you see it. As I said the sensor makes no difference, that would just vary the cropping of what you are photographing.

Hmmm... It is clear you haven't understood what I'm saying, which surpises me. It wasn't about sensor size but about viewfinder size. In fact, I didn't mention sensor size at all....[??]

Never mind.
I think it is best to drop it.
Best wishes.

-- hide signature --

Regards,
Baz
"Ahh... But the thing is, these guys were no ORDINARY time travellers!"

I think we might agree but are talking about different things. But try my theory anyway, that is how I work out what  normal focal length is.

Barrie Davis
Barrie Davis Forum Pro • Posts: 21,460
Old book correct as far as it goes

jvkelley wrote:

I spent a few minutes on Google to try to find the oldest possible reference to a "normal" lens. The oldest thing I could find was a book called "The Exhibition Print" published in 1922. On page 367, the author refers to a normal lens having an angle of view of about 45 degrees. This would be 52mm on a full frame camera. This was published back when view cameras with various sized films were common.

So, this suggests that a "normal" lens is one that is neither wide-angle nor long-focus, but has a focal-length (AoV) lying midway between the two.

Well, what the old book says sounds perfectly fine to me, even if it isn't saying very much....

What I take exception to is the idea that this normal lens length (AoV) has anything to do with how the EYE sees things, either in Perspective, or Field of View.

(I wonder what the 1922 book says about lens hoods; they were practically unheard of at that time.)

-- hide signature --

Regards,
Baz
"Ahh... But the thing is, these guys were no ORDINARY time travellers!"

 Barrie Davis's gear list:Barrie Davis's gear list
Konica Minolta DiMAGE A2
Barrie Davis
Barrie Davis Forum Pro • Posts: 21,460
Re: Not the 50mm myth again. That one is tough to kill!

JulesJ wrote:

Barrie Davis wrote:

JulesJ wrote:

Barrie Davis wrote:

JulesJ wrote:

I sort of have to disagree with you here. If what you are seeing through your lens (and hence are photographing) is exactly the same as you see with your eyes, then I think that IS as standard as you can get.

Why? You do realise that the smaller the screen, the longer the lens you would choose after Size-match, don't you?

As you are fully aware, the rendering of perspective is the same for all f-lengths shooting from the same point is space....

.... so it doesn't matter which f-length happens to match your other eye's vision for SIZE as such... which will be different from one viewfinder system to another, or if you put on spectacles... (reading type glasses magnify AND reduce field of view.)

So, having dispensed with image SCALE as it appears through the viewfinder, all ELSE that varies as you zoom is Field of View... which, as I'm also sure you are aware, can't be pinned down in human vision, because it changes constantly depending on what you're looking at....

... like a room full of people scanned for the one you are there to meet, (wide angle)...

... or that very narrow section of road-width ahead that you are really REALLY concentrating on because you are flying towards it at 70mph. (telephoto)

And anyway, what if you are looking at a 3" LCD, or a waist-level finder as in a Rollieflex or Hasselblad, instead of an eyelevel finder?

Does the lens in use suddenly become NOT a 'normal' one because the viewfinding image as rendered on your retina is now vastly smaller than it was when the camera was pressed against your eye? I mean, viewfinder SIZE has changed hasn't it?

Indeed, its retinal size HAS changed, strictly because of viewfinding conditions, nothing else. The actual lens had no influence whatsoever.

It is a good job the viewfnder characteristic has nothing to do with what is, or is not, a normal lens.... otherwise photographic composition would be extremely confusing.

Matching the size and register between your viewfinder eye and the one looking directly past the camera is 10 seconds of mild amusement, and it would be fun if there was more to it in some way useful..

.... but it isn't, sadly

Ah I have to disagree with you here Barrie. The sensor size has nothing to do with what I am talking about. It is to do with distortion, compression of the image as in a wide angles shot and whatever the opposite is called with a long telephoto. The situation I describe is when there is neither compression or stretching (shall we call it)of the image. it is as natural as you you see it. As I said the sensor makes no difference, that would just vary the cropping of what you are photographing.

Hmmm... It is clear you haven't understood what I'm saying, which surpises me. It wasn't about sensor size but about viewfinder size. In fact, I didn't mention sensor size at all....[??]

Never mind.
I think it is best to drop it.
Best wishes.

I think we might agree but are talking about different things. But try my theory anyway, that is how I work out what normal focal length is.

I think a normal lens is one half-way between wide-angle and long-focus (tele), meaning it isn't either. It happens this f-length will approximate the image diagonal dimension.

That's ALL I think it is.

http://forums.dpreview.com/forums/post/50280416

I don't think such a lens has a "perspective that's like human vision", because lenses, whether on cameras or on the front of the head, don't have perspectives... It is positions in space that have perspectives.

Neither can any one focal length match human vision for Field or Angle of View, because human vision constantly adapts how wide is the view it perceives depending on the seeing job it's carrying out.

Furthermore, we only have to look out through our own eyes to know for certain there is absolutely nothing resembling a hard framed limit to normal vision when taken as a whole. About 90° round to the side it FADES OFF to nothing after growing increasingly blurred at the limits.

We don't need a photographic training to see this..

-- hide signature --

Regards,
Baz
"Ahh... But the thing is, these guys were no ORDINARY time travellers!"

 Barrie Davis's gear list:Barrie Davis's gear list
Konica Minolta DiMAGE A2
jrtrent Veteran Member • Posts: 4,407
Re: A normal lens has about a 45 degree angle of view -From 1922 book.

That's a great little booklet; thanks for pointing it out.  I need to remember to take greater advantage of all the free reading material Google and other sources make available.

About the angle of view, the author didn't specify whether he was talking about horizontal or diagonal angle of view, but the 2 1/4 X 3 1/4 Icarette camera he used for plate 1 had a 105mm normal lens, which corresponds pretty closely to a 45mm lens on a 35mm format camera.  A major part of his article, however, was improving the prints you choose to hang by cropping, manipulating L-shaped frames on a proof of the original negative to "find the picture," which, of course, gives the resulting image an even narrower angle of view.

I still agree with Tamron that "normal" isn't a single focal length, but can be anywhere between 40 and 60 mm (for a 35mm format camera), but I'm intrigued by the Journal of Vision abstract I referenced above which found focal lengths of 50-70mm to produce the least compression/expansion effects in images viewed by their test subjects.  I already know from experience that I personally find focal lengths shorter than 50mm too wide for my tastes, but I'll have to experiment more with focal lengths up to 70mm.

JulesJ
JulesJ Forum Pro • Posts: 44,871
Re: Not the 50mm myth again. That one is tough to kill!

Barrie Davis wrote:

JulesJ wrote:

Barrie Davis wrote:

JulesJ wrote:

Barrie Davis wrote:

Ah I have to disagree with you here Barrie. The sensor size has nothing to do with what I am talking about. It is to do with distortion, compression of the image as in a wide angles shot and whatever the opposite is called with a long telephoto. The situation I describe is when there is neither compression or stretching (shall we call it)of the image. it is as natural as you you see it. As I said the sensor makes no difference, that would just vary the cropping of what you are photographing.

Hmmm... It is clear you haven't understood what I'm saying, which surpises me. It wasn't about sensor size but about viewfinder size. In fact, I didn't mention sensor size at all....[??]

Never mind.
I think it is best to drop it.
Best wishes.

I think we might agree but are talking about different things. But try my theory anyway, that is how I work out what normal focal length is.

I think a normal lens is one half-way between wide-angle and long-focus (tele), meaning it isn't either. It happens this f-length will approximate the image diagonal dimension.

That's ALL I think it is.

http://forums.dpreview.com/forums/post/50280416

I don't think such a lens has a "perspective that's like human vision", because lenses, whether on cameras or on the front of the head, don't have perspectives... It is positions in space that have perspectives.

Neither can any one focal length match human vision for Field or Angle of View,

I think it does.

because human vision constantly adapts how wide is the view it perceives depending on the seeing job it's carrying out.

I don't think it does. We do not zoom in and out. All we have is looking, ie the direction we concentrate on and focus. (we also have auto f-stop as in our iris bit this makes no difference in this example)

Furthermore, we only have to look out through our own eyes to know for certain there is absolutely nothing resembling a hard framed limit to normal vision when taken as a whole. About 90° round to the side it FADES OFF to nothing after growing increasingly blurred at the limits.

We don't need a photographic training to see this..

What you are talking about is the crop of what we see. This is circular and as you say fades at the edges. ie a vignette.

-- hide signature --

Regards,
Baz
"Ahh... But the thing is, these guys were no ORDINARY time travellers!"

jrtrent Veteran Member • Posts: 4,407
Re: 50mm "Normal" Lens... Ok, but "Normal" on FF or APS-C Sensor?

jrtrent wrote:

I haven't seen the full study, but there's an interesting abstract at Journal of Vision on depth compression and expansion in photographs.

http://www.journalofvision.org/content/11/11/65.abstract

"Photographs taken with long focal length lenses appear to be compressed in depth and those taken with short focal lengths appear expanded. A common rule in photography is to use a 50-mm lens to create a natural-looking image (i.e., neither compressed nor expanded in depth). We hypothesized that this rule is a byproduct of people's viewing habits and an inability to take viewing distance into account."

What they found is that not only do people have "an inability to take distance into account when interpreting 3D contents of the photograph," the preferred viewing distance is mostly determined by print size, thus they stand too far from pictures taken with wideangle lenses and too close to pictures taken with telephoto lenses. The study found that images taken with lenses between 50 and 70mm were least susceptible to perceived compression/expansion effects.

It's possible that the 50-70mm range quoted above is a misprint in the abstract I referenced.  I found another abstract of the same research, and it said, "The effects are minimized when the focal length is 40-60mm." http://f1000.com/posters/browse/summary/1263

I'll have to see if I can get access to the full presentation at some point.

jrtrent Veteran Member • Posts: 4,407
Oops!

jrtrent wrote:

I still agree with Tamron that "normal" isn't a single focal length, but can be anywhere between 40 and 60 mm (for a 35mm format camera), but I'm intrigued by the Journal of Vision abstract I referenced above which found focal lengths of 50-70mm to produce the least compression/expansion effects in images viewed by their test subjects. I already know from experience that I personally find focal lengths shorter than 50mm too wide for my tastes, but I'll have to experiment more with focal lengths up to 70mm.

It's possible that the 50-70mm range quoted above is a misprint in the abstract I referenced. I found another abstract of the same research, and it said, "The effects are minimized when the focal length is 40-60mm." http://f1000.com/posters/browse/summary/1263

I'll have to see if I can get access to the full presentation at some point.

Edit:  On the website of one of the authors of the study, there is a short summary.  Here is part of it:

"Photographers, cinematographers, and computer-graphics engineers create striking pictorial effects. By using different focal length lenses, they can make a scene look compressed or expanded in depth, make a familiar object look natural or distorted . . . We examined the perceptual and geometric bases for why these effects work. We found that people’s preferred field of view when looking at pictures leads them to view long-focal-length pictures from too near and short-focal-length pictures from too far. By following the popular 50mm lens rule of thumb, photographers greatly increase the odds of a viewer looking at a photo from the correct distance, making the percept undistorted. . ." http://www.emilyacooper.org/Emily_A._Cooper/Photographic_Practice.html

Lee Jay Forum Pro • Posts: 52,227
Re: A normal lens has about a 45 degree angle of view -From 1922 book.

jrtrent wrote:

I still agree with Tamron that "normal" isn't a single focal length, but can be anywhere between 40 and 60 mm (for a 35mm format camera),

Or anywhere else.

but I'm intrigued by the Journal of Vision abstract I referenced above which found focal lengths of 50-70mm to produce the least compression/expansion effects in images viewed by their test subjects. I already know from experience that I personally find focal lengths shorter than 50mm too wide for my tastes,

This is a very accurate representation of how this scene looked to my eye.  Does this look natural or close to it to you?

-- hide signature --

Lee Jay
(see profile for equipment)

 Lee Jay's gear list:Lee Jay's gear list
Canon IXUS 310 HS Canon PowerShot SX260 HS Canon EOS 5D Canon EOS 20D Canon EOS 550D +22 more
Lee Jay Forum Pro • Posts: 52,227
Re: Oops!

jrtrent wrote:

"Photographers, cinematographers, and computer-graphics engineers create striking pictorial effects. By using different focal length lenses, they can make a scene look compressed or expanded in depth, make a familiar object look natural or distorted . . . We examined the perceptual and geometric bases for why these effects work. We found that people’s preferred field of view when looking at pictures leads them to view long-focal-length pictures from too near and short-focal-length pictures from too far. By following the popular 50mm lens rule of thumb, photographers greatly increase the odds of a viewer looking at a photo from the correct distance, making the percept undistorted. . ." http://www.emilyacooper.org/Emily_A._Cooper/Photographic_Practice.html

"the correct distance".  How is that defined?

http://en.wikipedia.org/wiki/IMAX#IMAX_Dome_.2F_OMNIMAX

"The dome system, which the San Diego Hall of Science called OMNIMAX, uses films shot with a camera equipped with a fisheye lens on the camera that squeezes a highly distorted 180° field of view onto the 65 mm IMAX film. The lens is aligned below the center of the frame and most of the bottom half of the circular field falls beyond the edge of the film. The part of the field that would fall below the edge of the dome is masked. When filming, the camera is aimed upward at an angle that matches the tilt of the dome. When projected through a matching fisheye lens onto a dome, the original panoramic view is recreated."

In other words, a 180 degree fisheye is "natural" for that viewing method.

-- hide signature --

Lee Jay
(see profile for equipment)

 Lee Jay's gear list:Lee Jay's gear list
Canon IXUS 310 HS Canon PowerShot SX260 HS Canon EOS 5D Canon EOS 20D Canon EOS 550D +22 more
Barrie Davis
Barrie Davis Forum Pro • Posts: 21,460
Re: Not the 50mm myth again. That one is tough to kill!

JulesJ wrote:

Barrie Davis wrote:

I think a normal lens is one half-way between wide-angle and long-focus (tele), meaning it isn't either. It happens this f-length will approximate the image diagonal dimension.

That's ALL I think it is.

http://forums.dpreview.com/forums/post/50280416

I don't think such a lens has a "perspective that's like human vision", because lenses, whether on cameras or on the front of the head, don't have perspectives... It is positions in space that have perspectives.

Neither can any one focal length match human vision for Field or Angle of View,

I think it does.

I know you do, but I think you are mistaken.

because human vision constantly adapts how wide is the view it perceives depending on the seeing job it's carrying out.

I don't think it does. We do not zoom in and out.

And I think it does. In effect, dynamically "zooming in and out" is EXACTLY what we do, the effective field width being that which we scan our eyeballs over.

It isn't an idea I came to by myself.

This was all part of a most interesting and informative lecture I attended on "Light, Colour and Vision" presented at the University of Surrey to local members of BIPP..

About 8 years later a good deal of the material was part of a "Horizon" documentary about how we see, with the original Surrey lecturer being one of the on-screen talking heads.

All we have is looking, ie the direction we concentrate on and focus. (we also have auto f-stop as in our iris bit this makes no difference in this example)

Furthermore, we only have to look out through our own eyes to know for certain there is absolutely nothing resembling a hard framed limit to normal vision when taken as a whole. About 90° round to the side it FADES OFF to nothing after growing increasingly blurred at the limits.

We don't need a photographic training to see this..

What you are talking about is the crop of what we see. This is circular and as you say fades at the edges. ie a vignette.

"Cropping" and "zooming in" are not significantly different from each other when we appreciate that all the perceptive processes we are talking about take place in the brain, not in the eyeball.

I am sorry we "see" this differently, Jules. ... but I'll get over it.

-- hide signature --

Regards,
Baz
"Ahh... But the thing is, these guys were no ORDINARY time travellers!"

 Barrie Davis's gear list:Barrie Davis's gear list
Konica Minolta DiMAGE A2
sherwoodpete
sherwoodpete Veteran Member • Posts: 7,766
Re: for me a "Normal" lens (...). is same 'size' view as 'no lens'
1

sdyue wrote:

for me a "Normal" lens (regardless of mm/fov/aov/sensor size)... is same 'size' view as 'no lens'

by 'no lens', i mean, 'no camera'... if i were to use a 50mm on a camera, and look through its OVF, and see an IDENTICAL 'size' (magnification of 1x) look compared to my bare eye with no camera in front of other eye... then i would see it as like 'no lens' at all.

it just happens that 50mm turned out to be closer to the 'no lens' look for FF (36x24mm frame)

It didn't "just happen". The viewfinder was engineered to give that degree of magnification.

It's also not relevant, since there are cameras with virtually non-existent viewfinders. For example a tiny image reflected in a little mirror for some folding rollfilm or box cameras. Or other cameras with a straight-through viewfinder incorporating no optical components, other than a hole to look through. And so on.

But all of those cameras, regardless of viewfinder, had a focal length chosen as "normal", and it clearly wasn't on the basis of how the viewfinder behaved.

Regards,
Peter

jrtrent Veteran Member • Posts: 4,407
correct distance

ljfinger wrote:

"the correct distance". How is that defined?

I'm thinking it's about the same way you and/or Barrie defined it.  In the abstract I linked to in a post above, they said, "The retinal images generated by a photograph and the original scene are the same when the viewer is at the photograph's center of projection (CoP). The distance of the CoP is the lens focal length multiplied by the print magnification. When viewers look at a photograph from closer or farther than the CoP, the geometric information in the retinal image specifies a scene that is respectively expanded or compressed."

In other words, a 180 degree fisheye is "natural" for that viewing method.

Thanks for that.  I'm only about an hour and a half drive from the Pacific Science Center in Seattle, and that's listed as a venue for IMAX.  I'll have to go see what it's like.  Seems to me I saw something similar as a kid at a fairgrounds, but the film they chose was of things like flying in a helicopter over mountainous terrain with unexpected dropoffs and such.  In my current state of decrepitude, a film like that would probably just induce a vertigo attack.

Keyboard shortcuts:
FForum MMy threads