Circular Polarizers, A Filter You Need
 

Hi All,

I've written the first of a series of articles on the use of real camera
filters with digital photography. The first is on the circular polarizer
filter:
http://www.dimagemaker.com/article.php?articleID=1063

Cheers,

Wayne
--
Wayne J. Cosshall
Publisher, The Digital ImageMaker, http://www.dimagemaker.com/
Blog http://www.digitalimagemakerworld.com/
Publisher, Experimental Digital Photography
http://www.experimentaldigitalphotography.com
Personal art site http://www.cosshall.com/

Circular Polarizers, A Filter You Need
 

"Wayne J. Cosshall" wrote in message
...
Hi All,

I've written the first of a series of articles on the use of real camera
filters with digital photography. The first is on the circular polarizer
filter:
http://www.dimagemaker.com/article.php?articleID=1063

Great article.

Thanks.

Circular Polarizers, A Filter You Need
 

On Aug 8, 5:33 am, "Wayne J. Cosshall" wrote:
Hi All,

I've written the first of a series of articles on the use of real camera
filters with digital photography. The first is on the circular polarizer
filter:

Cheers,

Wayne

I have one, rarely use it. Additionally, a 77mm multi-coated circular
polarizer to fit a great majority of my lenses, including my Mamiya
gear, costs a minimum of $150. It's not worth the money. And about
your examples, in the first series of thumbnail images, the one w/out
polarizer is clearly over exposed, the ones in which you indicate
reduced reflection from water and foliage are different, but not
necessarily better, and the darkened sky images look unnatural (and
again, you tend to overexpose, particularly in the ones with the dam
in the background). This is not to say the circular polarizer is not
without its uses, but to say it's a filter one "needs" is a stretch,
and a big one at that.

Finally, aren't you in essence spamming the photography groups in an
attempt to make money off our visits to your website, which are
replete with advertising? If you want to share info here, please do,
but your capitalist endeavors aren't welcome.

--
www.mattclara.com (not a single image there taken with a polarizer)

Circular Polarizers, A Filter You Need
 

Wayne J. Cosshall wrote:
Hi All,

I've written the first of a series of articles on the use of real
camera filters with digital photography. The first is on the circular
polarizer filter:
http://www.dimagemaker.com/article.php?articleID=1063

Cheers,

Wayne

I have a circular and a linear polariser. I was told that I would be better
to use the circular polariser on my digital camera, as it would give better
results.
But I've used both the linear and the circular polarisers on my digital and
I honestly can't see any difference in the results when I compare the two.

Circular Polarizers, A Filter You Need
 

"Fat Sam" wrote in message
...
Wayne J. Cosshall wrote:
Hi All,

I've written the first of a series of articles on the use of real
camera filters with digital photography. The first is on the circular
polarizer filter:
http://www.dimagemaker.com/article.php?articleID=1063

Cheers,

Wayne

I have a circular and a linear polariser. I was told that I would be
better to use the circular polariser on my digital camera, as it would
give better results.
But I've used both the linear and the circular polarisers on my digital
and I honestly can't see any difference in the results when I compare the
two.


The circular will tend to give slightly _poorer_ results, as it's designed
to let some polarized light through, as some camera's autofocus systems (and
ttl metering) depends upon it to get the job done.

--
www.mattclara.com

Circular Polarizers, A Filter You Need
 

In article ,
"Fat Sam" wrote:

But I've used both the linear and the circular polarisers on my digital and
I honestly can't see any difference in the results when I compare the two.

Nor should there be if they are the same quality. But under some
lighting conditions a linear polarizer will not let the AF or the AE or
both work properly if your camera has a beam splitter in the optical
system. If you have a camera without a beam splitter then you have no
reason to use a circular polarizer.

--
To reply no_ HPMarketing Corp.

Circular Polarizers, A Filter You Need
 

In article ,
"Matt Clara" wrote:


The circular will tend to give slightly _poorer_ results, as it's designed
to let some polarized light through, as some camera's autofocus systems (and
ttl metering) depends upon it to get the job done.

--
www.mattclara.com

No. They polarize exactly the same. All the quarter wave plate does is
allow some light to be processed properly by the AE or the AF, or both,
systems if your camera has a beam splitter in the optical path.

There are other factors that would make one type of polarizer more
effective then another. For instance a Kaesmann polarizer, linear or
circular, would be marginally more effective as the foil in a Kaesmann
is stretched tight in all directions and lies flatter then a simply
laminated polarizer. To keep the foil stretched tight the Kaesmann has
edge sealed glass rather then just laminated glass.

A properly hard coated polarizer with a modern MC that repels dust and
moisture while also passing up to 99.9% of the light hitting it to the
image plane (less what the polarizer eliminates of course) like the
Heliopan SH-PMC coated polarizers will be more effective then a coated,
uncoated or Kaesmann polarizer due to the coatings used. As well as the
quality of the foils used.

There are several grades of polarizers for optical use in photography.
Better polarizers use higher grades which are more color neutral and
have less effect on resolution then cheaper foils. The less expensive
polarizing filters may not be as effective due to the foil quality as
well as to the coatings and glass used.

--
To reply no_ HPMarketing Corp.

Circular Polarizers, A Filter You Need
 

Matt Clara wrote in news:1186583221.191643.258650
@x40g2000prg.googlegroups.com:

On Aug 8, 5:33 am, "Wayne J. Cosshall" wrote:
Hi All,

snip on the circular polarizer /snip

snip I have one, rarely use it. /snip

If you're photographing with a wide-ish lens, you might like the effect of
the Moose Peterson filter. It's a warm polarizer. I don't use it a lot,
but it gives a nice (think Fuji Astia) warm, saturated look to the skies
and skins.

Circular Polarizers, A Filter You Need
 

"Bob Salomon" wrote in message
...
In article ,
"Matt Clara" wrote:


The circular will tend to give slightly _poorer_ results, as it's
designed
to let some polarized light through, as some camera's autofocus systems
(and
ttl metering) depends upon it to get the job done.

--
www.mattclara.com

No. They polarize exactly the same. All the quarter wave plate does is
allow some light to be processed properly by the AE or the AF, or both,
systems if your camera has a beam splitter in the optical path.

There are other factors that would make one type of polarizer more
effective then another. For instance a Kaesmann polarizer, linear or
circular, would be marginally more effective as the foil in a Kaesmann
is stretched tight in all directions and lies flatter then a simply
laminated polarizer. To keep the foil stretched tight the Kaesmann has
edge sealed glass rather then just laminated glass.

A properly hard coated polarizer with a modern MC that repels dust and
moisture while also passing up to 99.9% of the light hitting it to the
image plane (less what the polarizer eliminates of course) like the
Heliopan SH-PMC coated polarizers will be more effective then a coated,
uncoated or Kaesmann polarizer due to the coatings used. As well as the
quality of the foils used.

There are several grades of polarizers for optical use in photography.
Better polarizers use higher grades which are more color neutral and
have less effect on resolution then cheaper foils. The less expensive
polarizing filters may not be as effective due to the foil quality as
well as to the coatings and glass used.



Damn, luminous landscape (and what I thought of as common knowledge) once
again let's us down:

"There are two types of polarizing filters available - linear or circular.
Linear polarizers are more effective and less expensive than circular ones.
But circular polarizers are needed with just about any camera that has a
through-the-lens metering system, or autofocus.

The reason for this is that both of these systems use semi-silvered mirrors
to siphon off some of the light coming though the lens. If that light is
linearly polarized it renders either the metering or the autofocus
ineffective. This means that you're going to have to buy circular polarizers
unless you're shooting with a pre-1970's camera, or a view camera."

--
www.mattclara.com

Circular Polarizers, A Filter You Need
 

In article ,
"Matt Clara" wrote:

The reason for this is that both of these systems use semi-silvered mirrors
to siphon off some of the light coming though the lens. If that light is
linearly polarized it renders either the metering or the autofocus
ineffective. This means that you're going to have to buy circular polarizers
unless you're shooting with a pre-1970's camera, or a view camera."

There is another reason that might effect some systems. And that is any
camera that has a polarized system in the viewfinder for display
readouts. If the camera has that type of display then as a linear
polarizer is rotated some display information may disappear and reappear
or be harder to read at some points of rotation then at others.

--
To reply no_ HPMarketing Corp.