Polarizing and Over-Polarizing

[ShunCheung]

In landscape photography, we frequently use polarizers to darken the

sky and emphasis the clouds, if any. Polarizers can also block

reflections and deepen the colors. However, sometimes we may also

over-polarize and get a near-black sky.

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Attached is an image of a Gum Tree on a hill, shot around 7 am (about

30 minutes after sun rise) with a 80-200 zoom at 200mm and Velvia

35mm film. The version on the left was shot with no filer, the version

on the right with a polarizer at its maximum effect.

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<img src="image?bboard_upload_id=9908684">

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Which one do you prefer?<div></div>

[dfdncithekxlbn8kaglf33]

The issue here is that you are shooting up into the tree's shadows. This just makes the tree dark in both images, and it is not a terrible inspriing image to begin with. The dark blue polarized sky looks unnatural to me. You could polarize this, but use far less. Remember it is not an on or off filter, but one that you have some control over. Just a dab will do you.

[rich815]

I'd prefer in between somewhere. The use of a polarizer is not a binary thing. You have all the nuances of all effects in between. Too many people do crank up the polarizer to full power and shoot the result is an overly polarized sky. It's hard not to do as the effect when looking through the lens and turning the polarizer is intoxicating as the colors richen and the sky deepens. Since it seems the effect when the slides come back is always more than you remember when you looked through the lens as a rule I find the setting I like while looking through the lens and then back off just a bit from there, then shoot.

[bill_proud]

Shun,

 

I like the un-polarized image but since there are no clouds it's a little harder to gauge. I'm glad you introduced this for discussion because I've been thinking a lot lately about stages of polarization versus always setting the polarizer at maximum effect. I tried backing off from maximum effect this week but don't have the film processed yet to see the results.

 

A second consideration I've been trying is camera angle to subject to minimize the percentage of shade or shadow in the scene.

 

One final thought is I feel it's extremely important to judge the look in print form as that is the end point of the process. Screen appearance and transparency viewing may look good but the pudding, to me, is the print.

[erick_lamontagne]

I prefer the second. Not so much for the sky but for the contrast and the shadows.

 

I made a quick experiment with Photoshop by selecting the blue sky and lightening it a bit. It looks better than the options we have IMO. The sky is lighter than the polarized photo but less hazy than the first. Something I will consider as an option in the future.

[david_henderson]

Of the two I prefer the one on the right since it has some life in the tree itself and a bit more vibrance in the foreground. Equally if the sky wasn't darker than the brighter parts of the foliage then the latter wouldn't stand out at all.

 

So whilst I'm entirely with those people who point out that it's possible to alter the degree of polarisation (and personally I seem to spend an awful lot of time twiddling polarisers and looking for sometimes minute changes in effect in the viewfinder) on this occasion I'd have gone for the darker sky quite deliberately for without it there is no picture at all.

 

Now I know that this is a photograph shot to make a point rather than something that's going to be cherished, but there is a point here that there are some occasions whern darkening the sky is vital to the success of an image. Equally there are situations where it is to be avoided at all costs. The point here is that it is not dark skies generically that are to be avoided, it's getting an over-darkened sky when you didn't mean to, and to this end learning the real capabilities of your polariser is extremely useful.

[robert_potts1]

I prefer the one on the right because there appears to be much more drama in the light. Some scenes appear to be naturally polarized. The polarizer is an extremely popular filter among chrome users for very good reasons.

[peza]

When polarizing effect can be really powerfull, because of angle of sun and air moisture, I shoot between 1/2-2/3 of "polarizing" effect power and especially with velvia, some shots can look really ridiculous. All that I find out after shooting in Greece (beautifull blue skies, clear air) which can compare only to winter skies in high mountains.<br><br>

<img src="http://www.photo.net/photodb/image-display?photo_id=847391&size=sm"> this I consider to be good polarization.<br>

<img src="http://www.photo.net/photodb/image-display?photo_id=847421&size=sm"> this is a bit overdone, to my liking (but water was really THAT BLUE!)<br>

<img src="http://www.photo.net/photodb/image-display?photo_id=847409&size=sm"> but this is only 0.5f ND grad, not more..

[gary_duffy]

From the reject heap.<div></div>

[bill_proud]

Shun,

 

I thought this image was outstanding when I saw it on the ground glass but after processing and especially in print form it sucked. It was the one that started me thinking about over polarization.

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<img src="image?bboard_upload_id=9910684">

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[keith_laban]

As well as darkening skies, polarizers also alter the colour intensity, but strangely enough not always increasing it. The sky in the un-polarized shot is fairly natural in tone but extremely garish. The sky in the polarized shot may be a little too dark, but has lost the cheap and garish look seen on far too many postcards. In fact the colour of the sky on the polarized shot has been reduced in intensity whilst the foliage and rock colour has been increased to good effect.

[keith_laban]

In this shot I wanted to maintain a fairly natural blue sky whilst increasing the colour intensity of the foliage. To achieve this I backed off a little on the polarizer.<div></div>

[paul_purcell]

Some of the color comes from glare reduction. I noticed the glare on the leaves, and out of curiosity, took max/min polarizer shots, and was surprised at the amount of color that appeared.<div></div>

[patrick_smeaton]

I intially was going to say the first one (due to the color of the sky on the

second one "looking" polarized. BUT, when taking other parts of the scene

into account I would have to say the second one.

 

I agree with Richard, somewhere in between would be best (the grass is

always greener....;-)

[ShunCheung]

Thanks a lot for all the responses. This is precisely the discussion I wanted to initiate. Sometimes I do feel that we spend way too much time discussion equipment in this forum, while a discussion of a simple topic such as polarizers is very useful.

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Yes, the images I included in my initial message are there to compare the effect of polarizing; they are certainly not some "great shots" to charish. They were shot last month in a cold morning after a sunrise shoot. I was experimenting around and made quite a few shots in that area, and this pair illustrate the effect of polarizing the best. When I took them I indeed had the thought about starting this thread, as I myself might have ruined some images by over-polarizing, and I also feel that some images posted to this forum are over-polarized.

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There are no right or wrong answers here, of course. I do agree that the polarized shot (right) has a very dark sky that looks unnatural.

However, the polarizer also brings out the color of the tree and the grass around the tree really stand out against a dark sky. So I think I prefer the polarized shot. But perhaps something in between would be best.

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<img src="image?bboard_upload_id=9912684">

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Another issue is film. Ten years ago I pretty much used Kodachrome exclusively, and I routinely used maximum polarization which worked very well. However, with modern high-contrast film such as Velvia or Ektachrome E100-VS, over-polarization becomes an issue.

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BTW, Bill Proud, I think you have a good shot. Obviously I don't get to see your original, but the image posted here has extreme contrast which is common in poor scans.<div></div>

[ron_niebrugge]

Shun,

 

This is an interesting discussion, and something I have spent some time pondering myself.

 

About a month ago we had some exceptionally dark blues skies where I live (along the coast of Alaska) and I had to chuckle because I felt a photo taken at that time would be criticized by some as being over polarized, even if a polarizer wasn�t used. I held up my polarizer as a test, and it had no effect on such a clear sky.

 

We know a polarizer does not make a sky bluer, it just removes the glare caused by reflection on particles in the sky at the time. We say it does not look natural, but what is natural. Maybe it is because we have gotten so use to seeing haze in the sky that we see a rich dark blue sky as un-natural, when maybe it is not. Sure plenty of haze is naturally created, forest fires, volcanos etc., but there is now a steady, year around supply of man made air pollution as well.

 

Where polarizer use really looks un-natural is with horizontal images taken with wide angles lens in which only some of the sky has the effect, and other parts do not.

[vince]

<p>Excellent debate, but that's really all it is: lots of creative people expressing their individual preference. Photography, like any form of art, is all about perception. Here's the real question Shun, which do <i><b>you</b></i> prefer? Art is lost when it's reduced to right and wrong.</p>

 

<p>On a lighter note and at the risk of introducing an equipment angle, what kind of polarizer are you using? I've been using a Moose Warming Polarizer (circular) and rarely see anything overpolarized. I remember an extreme difference between unpolarized and max-polarized back in the manual focus days.</p>

[ShunCheung]

As I pointed out earlier, I prefer the polarized one on the right, but the dark sky does look unnatural to me.

 

I think exactly which polarizer I used doesn't really matter. For the record, I used a Nikon 77mm polarizer; the type that widens in front, but you'll have pretty much the same trade off if you use a B&W, Hoya, or Tiffen, etc.

[jonmy7]

A side point.. I have found that using a polariser helps me get better composition as I spend more time planning the shot, i.e. get my angle to the light right, paying more attention to what the sky is doing. Anmyone else finf this too?

 

I forget who posted the example on this thread with the "before and after" on the trees but I think that is a lovely example, really showing that a polariser is much more than affecting the sky.

[dan_smith]

Any problems showing up in using different brands that are not truly Neutral? Some give color biases that can screw up an image. A few years ago I saw some head to head tests of various brands but can't find them now.

I think my favorite polarized photos (sarcastic here) are those who put them on 18mm or so lenses & try to pass off the dark band of polarization as 'haze' in the photo.

[Two23]

The polarized shot has better color in the red rock foreground, but the sky has gone a bit too dark. I agree that using the polarizer at 1/2 to 2/3 strength is the way to go. One thing that not everyone realizes is that at higher altitudes a polarizer can quickly over do it. I was at the Grand Canyon over the weekend, at elevations of 7,000 ft. I knew to watch out for the sky going too dark when using the polarizer! While I probably use a polarizer for about 65% of all my outdoor non-wildlife shots, I am careful to slowly dial it in to the amount desired.

 

 

Kent in SD<div></div>

[ShunCheung]

Well, if we may use non-nature examples in this thread, take a look at this image of the Sydney Opera House shot with my 17-35 zoom near 17mm. I used the same 77mm polarizer that was also used in that gum tree image (80-200 zoom at 200mm) that started this thread. The Opera House is right by Sydney Horbour; even at sea leavel but with a super wide, the sky looks almost black at full polarization. Now that is really un-natural. However, for a non-nature subject, I kind of like that effect against the white building top for one shot. But if every landscape image is like this, I think I'll get tired of it in no time.

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<img src="image?bboard_upload_id=9964584">

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[the lone ranger]

if you care about how natural things look, then why shoot pictures? the so called overpolarized picture looks way better in my opinion. the unpolarized one is just all one bland image, but then with the darkened sky everything pops off the screen a lot more. if any person were to buy your photos from you to use in an advertising project, the one on the right would be bought everytime from me anyway.

[ShunCheung]

Richard, there is no right or wrong amount of polarization here. Just like whether you like Velvia, E100VS, Provia 100F, Kodachrome or Astia; it is all personal preference. And our taste does change over time also. When Velvia first came out back in 1990, I didn't like it at all as it looked very exaggerated and unnatural to me, while many people dismissed it as "Disney Chrome." However, after a few years, people gradually got used to Veliva and it became the "standard" pro slide film. In the last 7, 8 years or so it has been my landscape film.

 

To sum up, back in the day of Kodachrome, full polarization was never a problem to me. Today with Velvia, full polarization may lead to a very dark sky in landscape shots. Until just a few years ago, most of us used 24mm wide angles for landscape and a 20mm was pretty extreme.

Today, those 16/17-35 zooms are quite popular. A polarizer at 16mm can easily lead to un-even polarization and a black sky. That is not necessarily "wrong," but some people may not like it that way.

 

This has been a very useful discussion to me. And before I forget, the two "before and after" images by Paul Purcell on removing glare form an excellent example. Thanks Paul.

[imaginator]

Personally, I don't like overly dark blue skies! I have seen many beautiful rich blue skies, in high elevation locations with clear air, but they never look that dark. Either reduce the polarized effect or use a different film... Velvia and full polarization is too much IMO.