50mm pictures with D300

On Tue, 22 Jan 2008 04:18:00 GMT, "Dudley Hanks"
wrote in Y7elj.36053$fj2.9840@edtnps82:

"John Navas" wrote in message
.. .

That childish response is actually correct. Moving with your feet is
*not* the same thing as zooming (changing focal length) because it
changes *perspective*, which zooming does not. It's why a "dolly zoom"
is not the same as lens zoom alone.

Aw, but does every zoom lens maintain the same degree of depth of field,
perspective, etc?

I think not.

I'm afraid you're wrong. Zoom lenses do maintain perspective, since the
distance to the subject doesn't change. As for depth of field:

http://www.cambridgeincolour.com/tutorials/depth-of-field.htm

Larger apertures (smaller F-stop number) and closer focal distances
produce a shallower depth of field.

....

Even though telephoto lenses appear to create a much shallower depth
of field, this is mainly because they are often used to make the
subject appear bigger when one is unable to get closer. If the
subject occupies the same fraction of the viewfinder (constant
magnification) for both a wide angle and a telephoto lens, the total
depth of field is virtually constant with focal length!

....

This exposes a limitation of the traditional DoF concept: it only
accounts for the total DoF and not its distribution around the focal
plane, even though both may contribute to the perception of
sharpness. A wide angle lens provides a more gradually fading DoF
behind the focal plane than in front, which is important for
traditional landscape photographs.

On the other hand, when standing in the same place and focusing on a
subject at the same distance, a longer focal length lens will have a
shallower depth of field (even though the pictures will show
something entirely different). This is more representative of
everyday use, but is an effect due to higher magnification, not focal
length. Longer focal lengths also appear to have a shallow depth of
field because they flatten perspective. This renders a background
much larger relative to the foreground-- even if no more detail is
resolved. Depth of field also appears shallower for SLR cameras than
for compact digital cameras, because SLR cameras require a longer
focal length to achieve the same field of view.

So, the only thing that is constant throughout a variety of zoom lenses is
that the area covered by the shot decreases and the objects in it become
larger.

They all have the same performance at a given focal length and
aperature.

For instance, are the effects produced by a 35mm to 80mm zoom exactly the
same as, let us say, a 100mm to 300mm zoom?

Of course not -- different focal lengths.

No, the shots from each would be much different, but the characteristical
magnification of the image is what is the goal.

The entire composition is the goal!

So, why can't one "zoom" with one's feet?

Because perspective changes. Compare the image taken with a 300 mm lens
to the same subject size with a 50 mm lens, and you'll find the
background is totally different! See
http://www.luminous-landscape.com/tutorials/dof2.shtml

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

"John Navas" wrote in message
...
On Tue, 22 Jan 2008 04:07:08 GMT, "Dudley Hanks"
wrote in MZdlj.36050$fj2.24929@edtnps82:

"David J. Littleboy" wrote in message
om...

"Dudley Hanks" wrote:

Some people are just too lazy to zoom with their feet.

People who suggest zooming with their feet should be introduced to the
nearest superhighway.

Some people are just too dependant on a technilogical crutch.

Zoom isn't a crutch -- it's a tool.

When I want long perspective, moving in isn't an option.

You do understand perspective, right?

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

Probably better than you can imagine.

But, this thread started out with the suggestion that, once and a while, we
should put the zooms away and trudge around town a bit in order to check out
the 50mm perspective, and what effects can be obtained by "zooming" with our
feet.

You do understand the original intent of the thread, right?

These posts received a resounding, unwarranted, ridicule, and I merely
attempted to support the original two posters by defending the proposal.

Given the high tech, mega-featured cameras we all have today, it's easy to
rely on the technology to capture a stunning image. But, how many of
today's point and shooters would even own a camera if they had to put in the
same degree of work that photographers routinely exerted 30, 50, or more
yeears ago?

Of course, the flip side is: if people tried the 50mm challenge and found
out that a bit of physical exertion and creative thought can yield as much
of an improvement in our current images, imagine what could happen if a
similar degree of effort and creative thought were to be employed in using
our little pocket sized cameras.

I think the exercise at least deserves a try, and the proponents of the
concept a bit of respect.

Take Care,
Dudley

Beauty isn't always found in the eye of the beholder. Sometimes, it can be
found in the mind as well.

"John Navas" wrote in message
...
On Tue, 22 Jan 2008 04:18:00 GMT, "Dudley Hanks"
wrote in Y7elj.36053$fj2.9840@edtnps82:

"John Navas" wrote in message
. ..

That childish response is actually correct. Moving with your feet is
*not* the same thing as zooming (changing focal length) because it
changes *perspective*, which zooming does not. It's why a "dolly zoom"
is not the same as lens zoom alone.

Aw, but does every zoom lens maintain the same degree of depth of field,
perspective, etc?

I think not.

I'm afraid you're wrong. Zoom lenses do maintain perspective, since the
distance to the subject doesn't change. As for depth of field:

http://www.cambridgeincolour.com/tutorials/depth-of-field.htm

Larger apertures (smaller F-stop number) and closer focal distances
produce a shallower depth of field.

...

Even though telephoto lenses appear to create a much shallower depth
of field, this is mainly because they are often used to make the
subject appear bigger when one is unable to get closer. If the
subject occupies the same fraction of the viewfinder (constant
magnification) for both a wide angle and a telephoto lens, the total
depth of field is virtually constant with focal length!

...

This exposes a limitation of the traditional DoF concept: it only
accounts for the total DoF and not its distribution around the focal
plane, even though both may contribute to the perception of
sharpness. A wide angle lens provides a more gradually fading DoF
behind the focal plane than in front, which is important for
traditional landscape photographs.

On the other hand, when standing in the same place and focusing on a
subject at the same distance, a longer focal length lens will have a
shallower depth of field (even though the pictures will show
something entirely different). This is more representative of
everyday use, but is an effect due to higher magnification, not focal
length. Longer focal lengths also appear to have a shallow depth of
field because they flatten perspective. This renders a background
much larger relative to the foreground-- even if no more detail is
resolved. Depth of field also appears shallower for SLR cameras than
for compact digital cameras, because SLR cameras require a longer
focal length to achieve the same field of view.

So, the only thing that is constant throughout a variety of zoom lenses is
that the area covered by the shot decreases and the objects in it become
larger.

They all have the same performance at a given focal length and
aperature.

For instance, are the effects produced by a 35mm to 80mm zoom exactly the
same as, let us say, a 100mm to 300mm zoom?

Of course not -- different focal lengths.

No, the shots from each would be much different, but the characteristical
magnification of the image is what is the goal.

The entire composition is the goal!

So, why can't one "zoom" with one's feet?

Because perspective changes. Compare the image taken with a 300 mm lens
to the same subject size with a 50 mm lens, and you'll find the
background is totally different! See
http://www.luminous-landscape.com/tutorials/dof2.shtml

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

But, you are missing my point.

You admitted, above, that the effects of a small zoom are not the same as
the effects produced by a bigger zoom because "they don't have the same
focal length. And, this is the basis of my point.
While both lenses are different, and produce different affects, which is to
say that the depth of field and perspective of images produced with
differing zooms are different, we still refer to the process of magnifying
the effective image area as "zooming."

So, why can we not use the term when refering to the magnification of an
image by physically moving closer. The depth of field and perspective may
be different from those produced by physically changing the focal length of
a lens, but then, so are the effects of changing the focal lengths of any
two not identical "zoom" lenses.

Right?

Take Care,
Dudley

Beauty isn't always in the eye of the beholder. Sometimes, it can be found
in the mind as well.

On Tue, 22 Jan 2008 04:42:42 GMT, "Dudley Hanks"
wrote in 6velj.36054$fj2.20545@edtnps82:

"John Navas" wrote in message
.. .

Zoom isn't a crutch -- it's a tool.
When I want long perspective, moving in isn't an option.
You do understand perspective, right?

Probably better than you can imagine.

But, this thread started out with the suggestion that, once and a while, we
should put the zooms away and trudge around town a bit in order to check out
the 50mm perspective, and what effects can be obtained by "zooming" with our
feet.

It actually started off with a zoom not being available.

You do understand the original intent of the thread, right?

You did read the OP, right?

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

On Tue, 22 Jan 2008 04:56:12 GMT, "Dudley Hanks"
wrote in MHelj.36056$fj2.3282@edtnps82:

But, you are missing my point.

You admitted, above, that the effects of a small zoom are not the same as
the effects produced by a bigger zoom because "they don't have the same
focal length. And, this is the basis of my point.

What is your point?

While both lenses are different, and produce different affects, which is to
say that the depth of field and perspective of images produced with
differing zooms are different, we still refer to the process of magnifying
the effective image area as "zooming."

Depth of field does not change with focal length -- it changes with
focal distance. See the links in my prior message.

So, why can we not use the term when refering to the magnification of an
image by physically moving closer. The depth of field and perspective may
be different from those produced by physically changing the focal length of
a lens, but then, so are the effects of changing the focal lengths of any
two not identical "zoom" lenses.

Right?

No. If you keep subject magnification the same, depth of field doesn't
change. What does change with focal length is perspective, which is why
"walking zoom" and lens zoom are different. The change in perspective
may be desirable, or it may not.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

"John Navas" wrote in message
...
On Tue, 22 Jan 2008 04:42:42 GMT, "Dudley Hanks"
wrote in 6velj.36054$fj2.20545@edtnps82:

"John Navas" wrote in message
. ..

Zoom isn't a crutch -- it's a tool.
When I want long perspective, moving in isn't an option.
You do understand perspective, right?

Probably better than you can imagine.

But, this thread started out with the suggestion that, once and a while,
we
should put the zooms away and trudge around town a bit in order to check
out
the 50mm perspective, and what effects can be obtained by "zooming" with
our
feet.

It actually started off with a zoom not being available.

You do understand the original intent of the thread, right?

You did read the OP, right?

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

Okay, now it's starting to make sense. You don't know how to read. Please
note the following:


While I was waiting for my new zoom lens, I only had the 50mm left. So I
thought about something someone said someday: take pictures without a
zoomlens to learn composition.
So for all you boys and girls I hauled my camera around town and tried to
see....
I think there's absolutely some truth in this. You do feel that you have to
"create" instead of zooming.
If I was successful?

Now, you are right that the first sentence is about waiting for the lens,
the restt is about "zooming" with one's feet (although that particular term
didn't come in until a later reply).

I take it you didn't do very well in litrature class when your instructor
asked, "What's the main idea of this essay?"

Right?

Take Care,
Dudley

Beauty isn't always found in the eye of the beholder. Sometimes it is found
in the mind as well.

On Tue, 22 Jan 2008 05:28:54 GMT, "Dudley Hanks"
wrote in qaflj.36057$fj2.22341@edtnps82:

"John Navas" wrote in message
.. .

It actually started off with a zoom not being available.

You do understand the original intent of the thread, right?

You did read the OP, right?

Okay, now it's starting to make sense. You don't know how to read.

"Discussion" over.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

"John Navas" wrote in message
...
On Tue, 22 Jan 2008 04:56:12 GMT, "Dudley Hanks"
wrote in MHelj.36056$fj2.3282@edtnps82:

But, you are missing my point.

You admitted, above, that the effects of a small zoom are not the same as
the effects produced by a bigger zoom because "they don't have the same
focal length. And, this is the basis of my point.

What is your point?

While both lenses are different, and produce different affects, which is
to
say that the depth of field and perspective of images produced with
differing zooms are different, we still refer to the process of magnifying
the effective image area as "zooming."


The above is my point.

Depth of field does not change with focal length -- it changes with
focal distance. See the links in my prior message.

But, two different telephotos will likely produce differing depth of field
at the same focal length, right? Besides, find an old telephoto lens, lets
say a pre 1980's vintage, and look at the depth of field scale on the lens
as you move the focal length. Then come back and tell me that the depth of
field does not change with focal length.


So, why can we not use the term when refering to the magnification of an
image by physically moving closer. The depth of field and perspective may
be different from those produced by physically changing the focal length
of
a lens, but then, so are the effects of changing the focal lengths of any
two not identical "zoom" lenses.

Right?

No. If you keep subject magnification the same, depth

But, this is the crux of the matter. We don't want to keep the subject
magnification constant. We want to play with subject magnification which is
what the whole idea of this thread is about.

of field doesn't
change. What does change with focal length is perspective, which is why
"walking zoom" and lens zoom are different. The change in perspective
may be desirable, or it may not.

Let me try this from a different angle.

Imagine for a moment that you and I are the first two opticians in the world
who think up the idea of moving one element of a multiple element lens
farther away from the other.

I say to you, "Isn't this neat? As we zoom this element farther away, the
image gets bigger!"

And, you reply, "Yeah, that's nice. But what's going to sell this baby is
what it does to perspective!"

We immediately part company, and start marketing our own version of the
lens. Who do you think will be the better sales person?


Take Care,
Dudley

Beauty isn't always in the eye of the beholder. Sometimes, it can be found
in the mind as well.

"Dudley Hanks" wrote in message
news:xyflj.36058$fj2.34964@edtnps82...
Depth of field does not change with focal length -- it changes with
focal distance. See the links in my prior message.

But, two different telephotos will likely produce differing depth of field
at the same focal length, right?

Given the same magnification, wrong.

Besides, find an old telephoto lens, lets
say a pre 1980's vintage, and look at the depth of field scale on the lens
as you move the focal length. Then come back and tell me that the depth
of
field does not change with focal length.

Now try that again but this time changing the focus distance to maintain the
same magnification as you zoom.

But, this is the crux of the matter. We don't want to keep the subject
magnification constant.

No point in comparing apples to oranges then.

We want to play with subject magnification which is
what the whole idea of this thread is about.

I don't remember the OP saying that? In fact these were his words :
"take pictures without a zoom lens to learn composition".

MrT.


MrT.

"Rita Berkowitz" wrote:
Sosumi wrote:

While I was waiting for my new zoom lens, I only had the 50mm left.
So I thought about something someone said someday: take pictures
without a zoomlens to learn composition.
So for all you boys and girls I hauled my camera around town and
tried to see....
I think there's absolutely some truth in this. You do feel that you
have to "create" instead of zooming.

You got it! You did good. I love the old 50 and it is nice to be able to
get the results you want by zooming with your feet.

I'm a relative pup to photography. I've only been doing it for 8 years now.
So to clarify the "Zooming with your feet" thing. I read that as a
"creative analogy."

That's how it was meant, right?

Also, why do the Beatles start singing in my head whenever I read a post by
you?

:O)

Have fun,
Dave