A Photography forum. PhotoBanter.com

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » PhotoBanter.com forum » Digital Photography » Digital Photography
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

perspective w/ 35mm lenses?



 
 
Thread Tools Display Modes
  #371  
Old August 10th 04, 04:45 AM
Nostrobino
external usenet poster
 
Posts: n/a
Default On perspective


"mcgyverjones" wrote in message
. ..

"Nostrobino" wrote in message
. ..

"mcgyverjones" wrote in message
.. .

"Anthony Ralph" wrote in message
...
mcgyverjones wrote:
:: "Nostrobino" wrote in message
:: . ..
:::

[...]

::: He isn't "cropping" anything, any more than using a normal f.l.
::: lens is "cropping" what WOULD have appeared in a wide-angle

shot.
::: He's using the 300mm lens because that is what gives him the
::: perspective he wants. Does this also imply a more distant

camera
::: position? Obviously!



:: And it's the distance that provides the perspective, not the

focal
:: length.

Surely he is using the 300mm lens to acheive the field of view he

wants.
Perspective is a function of camera to object distance.

Exactly. Now tell Nostrobino that (or beat your head against the

wall).

I am beginning seriously to doubt that half of you even know what
"perspective" means. (Other than "duhhhh, something to do with camera
position.")

I don't see a lot of duhhh's here. But we do have a pretty fundamental
disagreement on what perspective means. As far as I am concerned this

feels
like trying to explain that the earth orbits the sun.

Perspective in a photograph is a result of camera position.


That, and focal length. You cannot produce wide-angle perspective with a
long-focus lens, regardless of camera position. I have said this several
times already. No one has refuted it and no one can.

If perspective really were only "a result of camera position" then obviously
you could get any perspective you wanted simply by moving the camera around.
You can't.


Wide angle photographs look different than normal or tele photos, but the
difference is not perspective (even though lots of people think it is and
call it that).


Those lots of people are perfectly correct in doing so. The difference is
perspective. They can see it, I can see it, and I'll bet you could see it
before you read some nonsense that told you it wasn't really there.

How would you define "perspective"? Not what causes it, what IS it? What do
you see in a picture that you call perspective? Answer that correctly and
you have to admit that wide-angle perspective (etc.) exists.



Telephoto lenses do not compress the subject, but the camera to subject
distances commonly utilized in tele shots show what we call compressed
perspective.


The spatial compression demonstrated by long lenses results from their
magnification and small angle of view. The change in apparent object
relationships (position, size, angles etc.) that this produces certainly
does qualify as a change in perspective.

A photographer may choose a particular focal length to gain a large field of
view (as in interior photography), high magnification (wildlife photography)
or pleasing perspective (portrait photography). While these things are all
necessarily interrelated, they are entirely different reasons for selecting
focal lengths.

In each case, camera position is simply what it has to be in order to get
the desirted result with the lens selected. Thus you may hear a photographer
say, "I like to use a 100mm lens for portraits"--rather than, for example,
"I like to shoot portraits from a distance of about seven feet." He chooses
the focal length for the perspective he wants, and the camera position
follows from that. Not the other way around.


  #372  
Old August 10th 04, 04:45 AM
Nostrobino
external usenet poster
 
Posts: n/a
Default


"mcgyverjones" wrote in message
. ..

"Nostrobino" wrote in message
. ..

"mcgyverjones" wrote in message
.. .

"Anthony Ralph" wrote in message
...
mcgyverjones wrote:
:: "Nostrobino" wrote in message
:: . ..
:::

[...]

::: He isn't "cropping" anything, any more than using a normal f.l.
::: lens is "cropping" what WOULD have appeared in a wide-angle

shot.
::: He's using the 300mm lens because that is what gives him the
::: perspective he wants. Does this also imply a more distant

camera
::: position? Obviously!



:: And it's the distance that provides the perspective, not the

focal
:: length.

Surely he is using the 300mm lens to acheive the field of view he

wants.
Perspective is a function of camera to object distance.

Exactly. Now tell Nostrobino that (or beat your head against the

wall).

I am beginning seriously to doubt that half of you even know what
"perspective" means. (Other than "duhhhh, something to do with camera
position.")

I don't see a lot of duhhh's here. But we do have a pretty fundamental
disagreement on what perspective means. As far as I am concerned this

feels
like trying to explain that the earth orbits the sun.

Perspective in a photograph is a result of camera position.


That, and focal length. You cannot produce wide-angle perspective with a
long-focus lens, regardless of camera position. I have said this several
times already. No one has refuted it and no one can.

If perspective really were only "a result of camera position" then obviously
you could get any perspective you wanted simply by moving the camera around.
You can't.


Wide angle photographs look different than normal or tele photos, but the
difference is not perspective (even though lots of people think it is and
call it that).


Those lots of people are perfectly correct in doing so. The difference is
perspective. They can see it, I can see it, and I'll bet you could see it
before you read some nonsense that told you it wasn't really there.

How would you define "perspective"? Not what causes it, what IS it? What do
you see in a picture that you call perspective? Answer that correctly and
you have to admit that wide-angle perspective (etc.) exists.



Telephoto lenses do not compress the subject, but the camera to subject
distances commonly utilized in tele shots show what we call compressed
perspective.


The spatial compression demonstrated by long lenses results from their
magnification and small angle of view. The change in apparent object
relationships (position, size, angles etc.) that this produces certainly
does qualify as a change in perspective.

A photographer may choose a particular focal length to gain a large field of
view (as in interior photography), high magnification (wildlife photography)
or pleasing perspective (portrait photography). While these things are all
necessarily interrelated, they are entirely different reasons for selecting
focal lengths.

In each case, camera position is simply what it has to be in order to get
the desirted result with the lens selected. Thus you may hear a photographer
say, "I like to use a 100mm lens for portraits"--rather than, for example,
"I like to shoot portraits from a distance of about seven feet." He chooses
the focal length for the perspective he wants, and the camera position
follows from that. Not the other way around.


  #373  
Old August 10th 04, 02:21 PM
Nostrobino
external usenet poster
 
Posts: n/a
Default On perspective


"mcgyverjones" wrote in message
. ..

"Nostrobino" wrote in message
...

"Jeremy Nixon" wrote in message
...
Nostrobino wrote:



I'm being generous. It might be called a spherical projection in the
sense that, if you represent the position of the object relative to the
camera in spherical polar coordinates (two angles and a distance), then
the position of the image point corresponding to the object is
determined by the two angles (but not the distance).

But you're right, it's not really a projection of a sphere onto a flat
surface, and not a spherical projection in the cartography sense.


Anyway, you're still the only person in the entire world who thinks

that
focal length affects perspective.


No, it's a common misconception.


It's a common and correct perception.




Actually, no, I'm far from "the only person in the entire world who

thinks"
that. Anyone who can see what's in front of him (and whose reasoning

power
has not been destroyed by reading nonsense) can see that a photo taken

with
a wide-angle lens has an entirely different perspective from a photo

taken
with a long lens from the same position. Unfortunately, you appear to be

one
of those so afflicted; as I recall you insisted repeatedly that there is

"no
such thing as a telephoto look," etc.


There is a telephoto look, it is derived from the distances that telephoto
photographs are commonly taken at.


The telephoto look (i.e., perspective) occurs with long lenses irrespective
of camera to subject distance. Do table-top photography with a long lens and
you still have the telephoto look.




Jeremy, the problem here is that you're trying to see the world

aroundyou
as the inside surface of a sphere, which it simply is not. It's a
three-dimensional world, made up of three-dimensional objects, and

all
a
rectilinear lens does is create a two-dimensional representation of

those
objects, whatever is in front of it that it's able to view.

And how does it do that? If it's not a spherical projection, what is

it?
You can't just say it makes a 2D representation of a 3D world; there

has
to be a method of doing that. Anyway, I'm not asking you, I'm

basically
done with you.


Go in peace then, brother, and enjoy the sphericity of your spherical

world.

So you really are a flat-earther?


No, I'm a three-dimensionaler. So you're agreeing with Jeremy that it's all
a spherical projection?



Actually, this whole sphere thing (as fascinating as it may be to some) is
irrelevant to perspective.


You will want to talk to Jeremy about that, not me.



To demonstrate how perspective can only be affected by camera position,


YES! YES! That is exactly what I have been asking people here to do, and
have had no takers. Just show me how you can get the same perspective with a
135mm lens (or whatever) that you do with a 28nn lens (or whatever). Use any
camera position you like to do that.


imagine various straight lines between the camera and subjects (fore, mid
and background). These lines represents the path of the cameras line of
site, or of light travelling from subject to camera.


So far, so good.


These lines define the
subject's relationship to one another and the background.


No, sorry, they do not. They define nothing but the directions from the
camera to those parts of the subject(s).


Of course they are
not affected by focal length,


Change the focal length and you get MORE such lines at wider angles, or
FEWER such lines at narrower angles. The lines you had before the f.l.
change are either added to, or subtracted from. Ergo, they are indeed
affected by focal length.


but change the camera position and all the
lines change. This is perspective, the relationships of objects to one
another.


But that isn't what you've just described. You've only described directions
from the camera to parts of the subject.



A telephoto lens has a look because it is commonly used at greater

distances
from main subject.


Again, this is just not necessarily true. That telephoto look occurs
regardless of distance. Long lenses are often used for portraiture at fairly
close distances, and I have already mentioned table-top photography. There
are many macro lenses (i.e., designed expressly for macro work) in the 90mm
to 200mm range, and of course they are used at close distances. In all of
these examples the long-lens look is still there. You do not get the same
perspective with a 180mm macro that you do with a 50mm macro.


similarly wide angle lenses have a look because their
wide field of view and great DOF is commonly used to include subjects

close
to the camera as they relate to subjects further away.


Wide-angle lenses are very commonly used for landscapes and other distant
shots, and DoF has nothing to do with perspective.



But the focal length itself has no bearing on the perspective.


As just (and repeatedly, repeatedly, repeatedly) illustrated, it does
indeed.



Choices made by lens designers affect how the scene is projected onto the
film/sensor plane, but they do not affect perspective.

This is actually pretty fundamental to photography, and the only reason

that
some of us have gone on about this is in the hope that perhaps someone

might
learn something.


That is my hope. Or at least, UNLEARN some of the nonsense they have
learned.


  #374  
Old August 10th 04, 02:21 PM
Nostrobino
external usenet poster
 
Posts: n/a
Default


"mcgyverjones" wrote in message
. ..

"Nostrobino" wrote in message
...

"Jeremy Nixon" wrote in message
...
Nostrobino wrote:



I'm being generous. It might be called a spherical projection in the
sense that, if you represent the position of the object relative to the
camera in spherical polar coordinates (two angles and a distance), then
the position of the image point corresponding to the object is
determined by the two angles (but not the distance).

But you're right, it's not really a projection of a sphere onto a flat
surface, and not a spherical projection in the cartography sense.


Anyway, you're still the only person in the entire world who thinks

that
focal length affects perspective.


No, it's a common misconception.


It's a common and correct perception.




Actually, no, I'm far from "the only person in the entire world who

thinks"
that. Anyone who can see what's in front of him (and whose reasoning

power
has not been destroyed by reading nonsense) can see that a photo taken

with
a wide-angle lens has an entirely different perspective from a photo

taken
with a long lens from the same position. Unfortunately, you appear to be

one
of those so afflicted; as I recall you insisted repeatedly that there is

"no
such thing as a telephoto look," etc.


There is a telephoto look, it is derived from the distances that telephoto
photographs are commonly taken at.


The telephoto look (i.e., perspective) occurs with long lenses irrespective
of camera to subject distance. Do table-top photography with a long lens and
you still have the telephoto look.




Jeremy, the problem here is that you're trying to see the world

aroundyou
as the inside surface of a sphere, which it simply is not. It's a
three-dimensional world, made up of three-dimensional objects, and

all
a
rectilinear lens does is create a two-dimensional representation of

those
objects, whatever is in front of it that it's able to view.

And how does it do that? If it's not a spherical projection, what is

it?
You can't just say it makes a 2D representation of a 3D world; there

has
to be a method of doing that. Anyway, I'm not asking you, I'm

basically
done with you.


Go in peace then, brother, and enjoy the sphericity of your spherical

world.

So you really are a flat-earther?


No, I'm a three-dimensionaler. So you're agreeing with Jeremy that it's all
a spherical projection?



Actually, this whole sphere thing (as fascinating as it may be to some) is
irrelevant to perspective.


You will want to talk to Jeremy about that, not me.



To demonstrate how perspective can only be affected by camera position,


YES! YES! That is exactly what I have been asking people here to do, and
have had no takers. Just show me how you can get the same perspective with a
135mm lens (or whatever) that you do with a 28nn lens (or whatever). Use any
camera position you like to do that.


imagine various straight lines between the camera and subjects (fore, mid
and background). These lines represents the path of the cameras line of
site, or of light travelling from subject to camera.


So far, so good.


These lines define the
subject's relationship to one another and the background.


No, sorry, they do not. They define nothing but the directions from the
camera to those parts of the subject(s).


Of course they are
not affected by focal length,


Change the focal length and you get MORE such lines at wider angles, or
FEWER such lines at narrower angles. The lines you had before the f.l.
change are either added to, or subtracted from. Ergo, they are indeed
affected by focal length.


but change the camera position and all the
lines change. This is perspective, the relationships of objects to one
another.


But that isn't what you've just described. You've only described directions
from the camera to parts of the subject.



A telephoto lens has a look because it is commonly used at greater

distances
from main subject.


Again, this is just not necessarily true. That telephoto look occurs
regardless of distance. Long lenses are often used for portraiture at fairly
close distances, and I have already mentioned table-top photography. There
are many macro lenses (i.e., designed expressly for macro work) in the 90mm
to 200mm range, and of course they are used at close distances. In all of
these examples the long-lens look is still there. You do not get the same
perspective with a 180mm macro that you do with a 50mm macro.


similarly wide angle lenses have a look because their
wide field of view and great DOF is commonly used to include subjects

close
to the camera as they relate to subjects further away.


Wide-angle lenses are very commonly used for landscapes and other distant
shots, and DoF has nothing to do with perspective.



But the focal length itself has no bearing on the perspective.


As just (and repeatedly, repeatedly, repeatedly) illustrated, it does
indeed.



Choices made by lens designers affect how the scene is projected onto the
film/sensor plane, but they do not affect perspective.

This is actually pretty fundamental to photography, and the only reason

that
some of us have gone on about this is in the hope that perhaps someone

might
learn something.


That is my hope. Or at least, UNLEARN some of the nonsense they have
learned.


 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Can Nikon DX lenses be used on 35mm bodies? Paul Crowder Digital Photography 6 July 11th 04 09:32 PM
New Leica digital back info.... Barney 35mm Photo Equipment 19 June 30th 04 12:45 AM
35mm C vs 35mm N mamiya 645 lenses Stacey Medium Format Photography Equipment 0 May 16th 04 07:06 AM
Asking advice Bugs Bunny Medium Format Photography Equipment 69 March 9th 04 06:42 AM
FA: Ricoh KR-10 35mm Camera, lenses, flash extras jon Other Photographic Equipment 1 February 8th 04 11:10 PM


All times are GMT +1. The time now is 06:51 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 PhotoBanter.com.
The comments are property of their posters.