Circular vs square grid polarizers: I know that for digital photography circular polarizers are necessary to prevent disturbing patterns. Do circular polarizers work properly with...

dbrugger25 Loc: Raleigh, NC

I know that for digital photography circular polarizers are necessary to prevent disturbing patterns.

Do circular polarizers work properly with film? Is there any known downside?

I have an old Crown Graphic 4 X 5 with an f:4.7 Schnider lens and would like to use a polarizing filter on it.

Longshadow Loc: Audubon, PA, United States

dbrugger25 wrote:

I know that for digital photography circular polarizers are necessary to prevent disturbing patterns.

...

I thought one needed a circular polarizer because a linear polarizer buggers the auto-focus system, not because of "patterns".

dbrugger25 Loc: Raleigh, NC

Longshadow wrote:

I thought one needed a circular polarizer because a linear polarizer buggers the auto-focus system, not because of "patterns".

I might be wrong but I thought that, since the sensor has a certain pixel pitch and the polarizer has a different linear pitch, a morae pattern will be generated. It will probably be noticed in the final photo and the pattern will also confuse the autofocus system.

Longshadow Loc: Audubon, PA, United States

dbrugger25 wrote:

I might be wrong but I thought that, since the sensor has a certain pixel pitch and the polarizer has a different linear pitch, a morae pattern will be generated. It will probably be noticed in the final photo and the pattern will also confuse the autofocus system.

I don't know, never used a linear on a digital.
There may be different results as the two are different methods of polarizing.
Proof in the pudding would to try one of each on a digital camera, and manual focus with the linear.

one_eyed_pete Loc: Colonie NY

dbrugger25 wrote:

I know that for digital photography circular polarizers are necessary to prevent disturbing patterns.

Do circular polarizers work properly with film? Is there any known downside?

I have an old Crown Graphic 4 X 5 with an f:4.7 Schnider lens and would like to use a polarizing filter on it.

A CPL filter has two filters. The first is a rotatable linear polarized filter to block light entering which is at 90 degrees from the alignment of the linear polarizer plane. The second filter is a Quarter wave plate which retards/changes the polarized light into unpolarized light so that auto focus and metering can function properly. The film surface or digital sensor wouldn't know the difference. Don't ask me how quarter wave plates work. I just viewed several videos explaining the physics and my head exploded.

The purpose of a CPL is to give you control over strong reflected light entering the lens because reflected light is highly polarized. Think sun reflecting off a pond or off a glass window.

charles brown Loc: Tennesse

dbrugger25 wrote:

I know that for digital photography circular polarizers are necessary to prevent disturbing patterns.

Do circular polarizers work properly with film? Is there any known downside?

I have an old Crown Graphic 4 X 5 with an f:4.7 Schnider lens and would like to use a polarizing filter on it.

I remember that when I made the switch from film to digital was told my film polarizers would not work on digital cameras and had to now use circular polarizers. Was told this by people at camera store and read it on the internet.

Longshadow Loc: Audubon, PA, United States

charles brown wrote:

I remember that when I made the switch from film to digital was told my film polarizers would not work on digital cameras and had to now use circular polarizers. Was told this by people at camera store and read it on the internet.

Did they tell you why or just "won't work".....

wdross Loc: Castle Rock, Colorado

dbrugger25 wrote:

I know that for digital photography circular polarizers are necessary to prevent disturbing patterns.

Do circular polarizers work properly with film? Is there any known downside?

I have an old Crown Graphic 4 X 5 with an f:4.7 Schnider lens and would like to use a polarizing filter on it.

With mirrorless cameras, one can use both circular or linear polarizers. If one has a DSLR, one should only use a circular polarizer. DSLRs tend to be built with partial mirrors that allows the passage of some light for metering off the sensor. It is the way that light is reflected/passed with the mirror that causes visual issues when a linear polarizer is used. Supposedly the linear polarizers produces a slightly darker and pronounce polarization effect. But the DSLR mirrors will create visual problems with linear polarizers. I still usually buy circular polarizers because I still have a few film cameras. But for cameras that are 4X5 and no internal metering, just get a linear polarizing filter.

User ID

Up to this point, NOTHING accurate has been posted. One or two posts are just somewhat off. The rest are truly outrageous.

Were I to post the facts, it would just generate argument and displays of gross stoopididdy. If you want the actual facts (which are pretty simple) read a reliable source, NOT a forum (any forum) and not some individuals blog.

I will only mention that LPL vs CPL has nothing whatsoever to do with whether the recording medium is film or a sensor, and that the origin of the problems are the Canon FTba and F-1 manual metering systems (mid 1970s).

rcarol

Longshadow wrote:

I don't know, never used a linear on a digital.
There may be different results as the two are different methods of polarizing.
Proof in the pudding would to try one of each on a digital camera, and manual focus with the linear.

I have found that a linear polarizer is more effective than a circular polarizer. I have not found a single issue using a linear polarizer with any of the cameras that I own.

User ID

rcarol wrote:

I have found that a linear polarizer is more effective than a circular polarizer. I have not found a single issue using a linear polarizer with any of the cameras that I own.

101% credible.

Bill_de Loc: US

User ID wrote:

Up to this point, NOTHING accurate has been posted. One or two posts are just somewhat off. The rest are truly outrageous.

I believe your statement is accurate. I'm glad you jumped in when you did. I was beginning to doubt everything I ever learned ... which ain't much to begin with.

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User ID

Bill_de wrote:

I believe your statement is accurate. I'm glad you jumped in when you did. I was beginning to doubt everything I ever learned ... which ain't much to begin with.

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The thread title is toadally bonkers as well.

selmslie Loc: Fernandina Beach, FL, USA

rcarol wrote:

I have found that a linear polarizer is more effective than a circular polarizer. I have not found a single issue using a linear polarizer with any of the cameras that I own.

User ID

Bill_de wrote:

I believe your statement is accurate. I'm glad you jumped in when you did. I was beginning to doubt everything I ever learned ... which ain't much to begin with.

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LPL vs CPL has no effect whatsoever on image recording. It affects only certain conveniences on certain semi-obsolete cameras. Metering can be less convenient but still functional. AF may be useless. Nothing else is ever affected. The CPL is headed for obsolescense along with the cameras that "needed" it.