MACRO SHOTS QUESTION

On Tue, 04 Jul 2006 14:30:20 GMT, Jeff Rife wrote:

John A. Stovall ) wrote in rec.photo.digital.slr-systems:
So, basically, a good P&S can beat a DSLR for close-up work. Do you agree?
What do I get with a DSLR and a macro lens?

No a POS will not beat a DSLR for Macro work. Care to compare your
images with a POS and my Canon 5D with 180mm Macro?

Image quality to start with.

Things like these...

http://www.photo.net/photodb/photo?photo_id=4522501

Although this shot is a nice close-up, it's not a macro shot. Unless,
of course, the bee is less than 1/4" long in real life.

Perhaps while you weren't looking, the term 'macro photography' has acquired
broader meaning than you prefer.

from http://en.wikipedia.org/wiki/Macrophotography
"In recent years, the term macro has come to mean being able to focus on a
subject close enough so that when a standard 102×152 mm (4×6 inch) print is
made, the image is life-size or larger."

I've been involved with this aspect of photography for more than thirty years,
and even when I began the term was in flux. Some people insisted that the very
narrow meaning (life size on the film) was the only right one, as you apparently
do. Others used the term more like wikipedia describes it. The others have
largely won, and at the present time the term 'macro photography' means making
larger-than-life photographic images of small subjects, as wikipedia correctly
notes..

All attempts to restrict spoken ('living') languages have always resulted in
failure. This applies even to the efforts of the Russian language academy under
the totalitarian regime of the Communists. You will have no more success than
they did, and will only wind up out of step with your fellow English language
users.

In article ,
writes
On Tue, 04 Jul 2006 14:30:20 GMT, Jeff Rife wrote:

John A. Stovall ) wrote in
rec.photo.digital.slr-systems:
So, basically, a good P&S can beat a DSLR for close-up work. Do
you agree?
What do I get with a DSLR and a macro lens?

No a POS will not beat a DSLR for Macro work. Care to compare your
images with a POS and my Canon 5D with 180mm Macro?

Image quality to start with.

Things like these...

http://www.photo.net/photodb/photo?photo_id=4522501

Although this shot is a nice close-up, it's not a macro shot. Unless,
of course, the bee is less than 1/4" long in real life.

Perhaps while you weren't looking, the term 'macro photography' has acquired
broader meaning than you prefer.

from http://en.wikipedia.org/wiki/Macrophotography
"In recent years, the term macro has come to mean being able to focus on a
subject close enough so that when a standard 102×152 mm (4×6 inch) print is
made, the image is life-size or larger."

This shows just how dangerous it is to rely on Wikipedia - where items
may be written by people with more spare time than knowledge. BTW, as
those more knowledgeable than the Wikipedia contributor know, the
preferred term is "photomacrography".

I've been involved with this aspect of photography for more than thirty years,
and even when I began the term was in flux. Some people insisted that the very
narrow meaning (life size on the film) was the only right one, as you
apparently
do. Others used the term more like wikipedia describes it. The others have
largely won, and at the present time the term 'macro photography' means making
larger-than-life photographic images of small subjects, as wikipedia correctly
notes..

Only by people not expert in the field.

All attempts to restrict spoken ('living') languages have always resulted in
failure. This applies even to the efforts of the Russian language academy under
the totalitarian regime of the Communists. You will have no more success than
they did, and will only wind up out of step with your fellow English language
users.

You are of course correct - language develops. However, where the
development involves degrading a usefully precise technical term into
meaningless mass-market advertising-speak, it is to be regretted, and
IMO it is right to try to resist it.

David
--
David Littlewood

David Littlewood wrote:

In article ,
writes
On Tue, 04 Jul 2006 14:30:20 GMT, Jeff Rife wrote:

John A. Stovall ) wrote in
rec.photo.digital.slr-systems:
So, basically, a good P&S can beat a DSLR for close-up work. Do
you agree?
What do I get with a DSLR and a macro lens?

No a POS will not beat a DSLR for Macro work. Care to compare your
images with a POS and my Canon 5D with 180mm Macro?

Image quality to start with.

Things like these...

http://www.photo.net/photodb/photo?photo_id=4522501

Although this shot is a nice close-up, it's not a macro shot. Unless,
of course, the bee is less than 1/4" long in real life.

Perhaps while you weren't looking, the term 'macro photography' has
acquired broader meaning than you prefer.

from http://en.wikipedia.org/wiki/Macrophotography
"In recent years, the term macro has come to mean being able to focus on a
subject close enough so that when a standard 102×152 mm (4×6 inch) print
is made, the image is life-size or larger."

This shows just how dangerous it is to rely on Wikipedia - where items
may be written by people with more spare time than knowledge. BTW, as
those more knowledgeable than the Wikipedia contributor know, the
preferred term is "photomacrography".

I've been involved with this aspect of photography for more than thirty
years, and even when I began the term was in flux. Some people insisted
that the very narrow meaning (life size on the film) was the only right
one, as you apparently
do. Others used the term more like wikipedia describes it. The others have
largely won, and at the present time the term 'macro photography' means
making larger-than-life photographic images of small subjects, as
wikipedia correctly notes..

Only by people not expert in the field.

All attempts to restrict spoken ('living') languages have always resulted
in failure. This applies even to the efforts of the Russian language
academy under the totalitarian regime of the Communists. You will have no
more success than they did, and will only wind up out of step with your
fellow English language users.

You are of course correct - language develops. However, where the
development involves degrading a usefully precise technical term into
meaningless mass-market advertising-speak, it is to be regretted, and
IMO it is right to try to resist it.

The problem is that with sensor size varying all over the place "1:1" is no
longer as "usefully precise" as "filling the frame with a field of x
dimensions or smaller".

David

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

In article , J. Clarke
writes
The problem is that with sensor size varying all over the place "1:1"
is no longer as "usefully precise" as "filling the frame with a field
of x dimensions or smaller".

It always worked for different sizes of film; macro is a property of the
lens to form a life size image.
--
Ian G8ILZ

In article , J. Clarke
writes
David Littlewood wrote:

You are of course correct - language develops. However, where the
development involves degrading a usefully precise technical term into
meaningless mass-market advertising-speak, it is to be regretted, and
IMO it is right to try to resist it.

The problem is that with sensor size varying all over the place "1:1" is no
longer as "usefully precise" as "filling the frame with a field of x
dimensions or smaller".

Many of the equations important for photomacrography involve
"magnification" as key parameter. Given that it is a precisely defined
term, and is useful, I have to disagree with your conclusion.

Sensor size is of course important - but the only thing it affects in
photomacrography is field of view. Depth of field, for example, is
determined only by magnification.

David
--
David Littlewood

Prometheus wrote:
In article , J. Clarke
writes
The problem is that with sensor size varying all over the
place "1:1" is no longer as "usefully precise" as "filling the
frame with a field of x dimensions or smaller".

It always worked for different sizes of film; macro is a
property of the lens to form a life size image.

It doesn't work well in defining _photomacrography_, which is
taking pictures of small things. A postage stamp is the same
size no matter whether you shoot the photo with a P&S digital
camera (an object larger than the sensor) or use an 8x10 view
camera (an object smaller than the sensor).

In any case the resulting 8x10 print is an example of
photomacrography, which will be *obvious* to anyone who looks at
it, even when they haven't a clue about the equipment used to
capture the image.

--
Floyd L. Davidson http://www.apaflo.com/floyd_davidson
Ukpeagvik (Barrow, Alaska)

Prometheus wrote:

In article , J. Clarke
writes
The problem is that with sensor size varying all over the place "1:1"
is no longer as "usefully precise" as "filling the frame with a field
of x dimensions or smaller".

It always worked for different sizes of film; macro is a property of the
lens to form a life size image.

For a limited range of standard sizes none of which were particularly small.

Basically you're saying that a camera that can fill the frame with an object
a half inch across has no macro capability while one having a larger sensor
but that cannot fill the frame with objects less than twice that size does
have macro capability, which seems to be more confusing than useful.

What's clear to me is that this is another one of those silly Internet
religions like "Mac vs PC" and "Intel vs AMD" and "Canon vs Nikon" that
some people insist on defending to the point of being killfiled.

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

In article , J. Clarke
writes
Prometheus wrote:

In article , J. Clarke
writes
The problem is that with sensor size varying all over the place "1:1"
is no longer as "usefully precise" as "filling the frame with a field
of x dimensions or smaller".

It always worked for different sizes of film; macro is a property of the
lens to form a life size image.

For a limited range of standard sizes none of which were particularly small.

Basically you're saying that a camera that can fill the frame with an object
a half inch across has no macro capability while one having a larger sensor
but that cannot fill the frame with objects less than twice that size does
have macro capability, which seems to be more confusing than useful.

I think you are looking at this issue from the wrong direction. It is -
always and without exception - an inherent property of the lens whether
it can form a 1:1 image. More precisely, it is an inherent property of
the lens mount that it can physically focus that close, and a property
of the optical design whether it produces good results at those
conjugates.

As I said in my other post, for a given lens, in photomacrography the
only factor which sensor size determines is field of view. A 90mm lens
at a 1:1 bellows extension can produce on 5x4 film a life size image of
a 5x4 subject; the same lens on a 36x24mm sensor can only produce a life
size image of the central 36x24mm of that subject. The DoF (on the
image, i.e. ignoring print magnification) and exposure will be
identical.*

The key point, and the real reason why people who actually do this kind
of thing use magnification as their key working parameter, is that for a
given lens the focal conjugates, the depth of field, and the exposure
correction are all determined by the magnification (and *only* by the
magnification). Sensor size does not even figure in this.

To reiterate - all sensor size does is determine field of view*. Now I
agree that it is important to know this, but whilst it is important in
deciding which lens to use for a given format, it tells you nothing
about how to use it correctly.

*Actually, this is slightly over-simplified - it also affects the amount
of magnification you are likely to choose to give the final image (print
or screen) and this factor - which is a matter of your choice and only
indirectly influenced by sensor size - will affect overall DoF.

Note that the above comments are only accurate for macro work (i.e. 1:1
or greater magnification).

What's clear to me is that this is another one of those silly Internet
religions like "Mac vs PC" and "Intel vs AMD" and "Canon vs Nikon" that
some people insist on defending to the point of being killfiled.

Well, if you think this, it is regrettable; it suggests (erroneously I'm
sure) that you have little interest in useful debate, and simply want to
repeat your preconceptions. Good debate leads (or should lead) to better
understanding on both sides. This is a newsgroup for discussing
equipment, and discussions of the choice and use of equipment is what it
is here for.

David
--
David Littlewood

David Littlewood wrote:

In article , J. Clarke
writes
David Littlewood wrote:

You are of course correct - language develops. However, where the
development involves degrading a usefully precise technical term into
meaningless mass-market advertising-speak, it is to be regretted, and
IMO it is right to try to resist it.

The problem is that with sensor size varying all over the place "1:1" is
no longer as "usefully precise" as "filling the frame with a field of x
dimensions or smaller".

Many of the equations important for photomacrography involve
"magnification" as key parameter. Given that it is a precisely defined
term, and is useful, I have to disagree with your conclusion.

Sensor size is of course important - but the only thing it affects in
photomacrography is field of view. Depth of field, for example, is
determined only by magnification.

And these equations no longer apply if the magnification is less than 1:1?
I'm sorry, but I don't see your point.

In any case, how often do you solve equations before taking a shot?

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

In article , J. Clarke
writes
David Littlewood wrote:

In article , J. Clarke
writes
David Littlewood wrote:

You are of course correct - language develops. However, where the
development involves degrading a usefully precise technical term into
meaningless mass-market advertising-speak, it is to be regretted, and
IMO it is right to try to resist it.

The problem is that with sensor size varying all over the place "1:1" is
no longer as "usefully precise" as "filling the frame with a field of x
dimensions or smaller".

Many of the equations important for photomacrography involve
"magnification" as key parameter. Given that it is a precisely defined
term, and is useful, I have to disagree with your conclusion.

Sensor size is of course important - but the only thing it affects in
photomacrography is field of view. Depth of field, for example, is
determined only by magnification.

And these equations no longer apply if the magnification is less than 1:1?
I'm sorry, but I don't see your point.

The precise equation for DoF is T = 2*f^2*u^2*N*C/(f^4-N^2*C^2*u^2),
where N is f-number, f is focal length and C is the circle of confusion
you have decided is acceptable.

Clearly this is quite unusable in practice. However, for distant scenes
(m1) the N^2**C^2*u^2 term is very small compared to the f^4 term and
the equation simplifies to T = 2*u^2*NC/f^2.

This is the equation you will most often see in discussions, but people
often forget it is an approximation only valid at distances where u f
(i.e. it's a long way away).

For close-up photography, where m is say 0.1, this approximation does
not work, but some different ones become valid, and

T = 2CN(1+m)/m^2

Thus in this region, DoF does not depend on lens focal length, but only
on magnification and lens aperture (and, as always, on the size of the
CoC you decide is acceptable).

In any case, how often do you solve equations before taking a shot?

If you are using a film camera with no built-in metering, always for
exposure measurement (true exposure = external meter exposure*(m+1)^2).
For DoF calculations, you need to do it unless you have a digital camera
and can review the results (at full resolution, not on the weedy little
preview screen) at once.

I agree, less essential today than 10 years ago, but still happens. I
feel the argument that "automation means you do not need to know how it
works" argument is dangerous - like believing that calculators mean you
don't need to know arithmetic.

In truth, I think this digression into arcane mathematics is obscuring
the real point (but you did ask....). This is that the generally
accepted definitions recognise these very real distinctions:

Close up photography (m = 0.1 to 1.0) is what you can do reasonably well
with conventional photographic gear (normal lenses plus close-up lenses
or extension tubes). Camera handling is fairly normal, and sunlight or
fairly simple artificial lighting works well.

Photomacrography (m 1.0) is what you can only reasonably do with
specialised gear (specialised macro lenses, bellows, rigid stands etc).
While hand-held work may be possible at the lower end, most work
requires very rigid stands (an order of magnitude better than most
people are used to using) and specialised lighting will normally be
required.

This is in fact the most useful definition, since it gives those coming
to the field a clear clue to what they need.

David
--
David Littlewood