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CapnBloodbeard
21-07-2012, 4:43pm
So, I was just musing on something after reading through this months' Australian Photography....

The polarising filter....has it had its day?

Now, we all know this is often regarded as an essential piece of equipment, and it's primary purpose is to enhance the blue in skies (though of course it can be misused).

But is this a throw-back to film days (particularly when very few of us processed our own prints)? I mean, colour/contrast adjustments in post are part of the normal photographic process these days, so does a polarising filter do anything that we wouldn't be doing on computer any way? Are we spending money, putting extra glass in front of our lenses and risking vignetting over a largely redundant piece of equipment?

Now, I know a polariser has other uses - cutting through reflections is something that can't really be done in post, and it can cut through a bit of glare as well, so perhaps that's now the primary use for a polariser in the age of digital photography?

So I guess my argument isn't so much that the filter is redundant, but the filter in the context of it's typical main use has become redundant and it's now only useful for its secondary purpose.

ricktas
21-07-2012, 5:30pm
The polariser is one filter that is very hard to replicate using software. There are some good examples out there (Nik Software's Polariser filter in their Color Efex Collection, is one) but they still do not have the full effect of a real polariser used on a lens.

I do not think the polariser has seen its end of days.

CapnBloodbeard
21-07-2012, 6:15pm
The polariser is one filter that is very hard to replicate using software

How so?

Kym
21-07-2012, 6:16pm
UVs are useless (ask kiwi :p)
Polarisers are VERY useful in glare and hard sky situations (they don't turn people blue either :)
Most other colour effects filters can be done in PP
Grad ND, Reverse Grad ND, and ND's are useful for taming the sky, sunsets and slowing the shutter in general

Kym
21-07-2012, 6:32pm
Polarisers change the nature of the light coming into the lens, i.e. aligning the light in a plain (over simplified, but sufficient for explanation)
Details
http://en.wikipedia.org/wiki/Polarization_%28waves%29
http://en.wikipedia.org/wiki/Polarizing_filter_%28Photography%29

This cannot be done in PP as the sensor will see all light rather than the aligned light and this cannot be undone later in the process.

Cris
21-07-2012, 6:35pm
Polarisers are great for rainforest pics, they add depth to the colour and help remove all this shiny reflective bits caused by wet surfaces.:)

MarkChap
21-07-2012, 6:35pm
Since when has the "primary" use for a polariser been to "enhance" the blue of the sky.

I have always considered the primary use of a polarise to cut down and through glare and reflections, or more correctly to reduce the polarised light.

old dog
21-07-2012, 7:10pm
they do enhance the clouds but on a wide angle they are a nightmare with the changing colours they create in the sky. Good shooting thru windows thus cutting the reflections back. Reducing your shutter speed also to get a slow water effect. Car photography also...cutting back unwanted reflectons.

geoffsta
21-07-2012, 8:37pm
I have one lens were the polariser is useless. The Tamron 90mm Macro. (Haven't used it as a macro yet) It seems to perform as if it had one.
But for the rest of my lenses they are necessity. Winter isn't too bad as long as I'm facing south. But during summer they are always on.
The other thing just as important is the lens hood. I see a lot of people using expensive cameras and lenses out in the middle of the day with no hood. And wonder why they have light issues.

Epicaricacy
21-07-2012, 9:25pm
I'm with mark chap... As far as aim concerned the primary use is to cut glare/reflections. A nie secondary effect is deeper blues and greens.

Paul G
21-07-2012, 11:00pm
Same as Mark C and Epic here. I use one mainly for shooting around water and especially for daylight car shoots and car shows.

ricktas
21-07-2012, 11:12pm
How so?

Try editing a photo to remove the glare off the surface of water to make the fish underneath more visible, using PP. A Polariser does this.

jjphoto
22-07-2012, 12:17am
A polarising filters main (not secondary) purpose is to control the passage of polarised light through it. Some times this makes the sky darker (which you can do in post), some times it allows you to see through reflective surfaces, glass, water etc, which can't be done in post, or only with great difficulty. It never ceases to amaze me how unpopular and misunderstood polarising filters are, at least with people who are new to photography. They will always be one of the most important tools in a camera bag as they have a very wide range of applications.

I virtually always carry a PL filter with me, even if I don't always need it.

http://photocornucopia.com/images/Automotive/l_143_pc_400.jpg http://photocornucopia.com/images/Automotive/l_141_pc_400.jpg

http://photocornucopia.com/images/Automotive/l_373_pc_400.jpg http://photocornucopia.com/images/Automotive/l_372_pc_400.jpg

http://photocornucopia.com/images/Automotive/l_148_pc_400.jpg http://photocornucopia.com/images/Automotive/l_149_pc_400.jpg

anon
22-07-2012, 1:00am
Another thing to consider is some people don't like to do a lot of post,
I prefer not post processing, the most I normally do is crop,
So for me a polarising filters have as much use as before the age of digital post ...

Regards,
Anon

CapnBloodbeard
22-07-2012, 2:23am
Since when has the "primary" use for a polariser been to "enhance" the blue of the sky.

I have always considered the primary use of a polarise to cut down and through glare and reflections, or more correctly to reduce the polarised light.

It's the most commonly referred to use for polarisers, whether it be in books, magazines, or online - enhancing colours is most commonly mentioned as the main reason to get a polariser :)

ricktas
22-07-2012, 7:59am
It's the most commonly referred to use for polarisers, whether it be in books, magazines, or online - enhancing colours is most commonly mentioned as the main reason to get a polariser :)

Interesting, that must be something reasonably new (in terms of how long polarisers have been around) as a way to describe their uses. Tthey were certainly originally described as being for reducing reflections and doing so by eliminating polarised light. Even wikipedia (http://en.wikipedia.org/wiki/Polarizing_filter_%28Photography%29) describes the use as for filtering out polarised light, and thus its purpose being to reduce reflections on surfaces, before it mentions darkening skies.

Until someone can come up with a good digital replication of what a polariser can do, they still serve a valuable purpose. As John has shown, their ability to remove reflections from surfaces (cars in his examples), cannot be fully replicated in PP at this time. especially on things like his second photo shows with the car windows.

bricat
22-07-2012, 8:25am
Thanks for asking the question Capn..... I have learnt something again.:)

gerry
22-07-2012, 8:50am
Saturation levels..by reducing the glare and reflections the colours are shown instead, giving a more saturated, or more correctly, true colours.

here are the two images that really show the marked difference a CPL can make. Both images processed identically.

No CPL

http://gerry.avernus.com.au/slide/files/3041_oubdy/GJB_3075-2.jpg


CPL

http://gerry.avernus.com.au/slide/files/3040_jgdoh/GJB_3074-2.jpg

Art Vandelay
22-07-2012, 9:16am
Definitely not dead over here either. Have one on often when out on that water mucking around in boats and fishing for the glare reasons noted above.

Even used it one night at a friends birthday party. I picked up the camera late one night after a few too many liquid refreshments and proceeded to take a few happy snaps. Took me quite a while to work out why the blazes I'm having to push the ISO so much when it wasn't even that dark...

CapnBloodbeard
22-07-2012, 11:27am
Saturation levels..by reducing the glare and reflections the colours are shown instead, giving a more saturated, or more correctly, true colours.

here are the two images that really show the marked difference a CPL can make. Both images processed identically.

No CPL




CPL



Great example there!!


Thanks for asking the question Capn..... I have learnt something again.:)

Glad you've found it helpful - my main purpose was to instigate a bit of discussion over the use of a common piece of equipment :)


Interesting, that must be something reasonably new (in terms of how long polarisers have been around) as a way to describe their uses. Tthey were certainly originally described as being for reducing reflections and doing so by eliminating polarised light. Even wikipedia (http://en.wikipedia.org/wiki/Polarizing_filter_%28Photography%29) describes the use as for filtering out polarised light, and thus its purpose being to reduce reflections on surfaces, before it mentions darkening skies.

. Not so much - as I said, its purpose in darkening skies is pretty useless now, IMO. Actually, you can probably get a safer result in PP, particularly with wide angle lenses. I've been into photography off and on for 10 years (since just before the 300D hit the market), and most materials I had then described a polariser as an essential piece of kit to enhance colour, especially in skies, and to cut through reflections. Enhancing colour always seemed to be either mentioned first or mentioned only :)


Until someone can come up with a good digital replication of what a polariser can do, they still serve a valuable purpose. As John has shown, their ability to remove reflections from surfaces (cars in his examples), cannot be fully replicated in PP at this time. especially on things like his second photo shows with the car windows.

I can't imagine that would ever happen - after all, the info that's been blocked by reflections is often info that has not reached the sensor at all, to varying extents.

Of course, I've sometimes taken advantage of a polariser just to block a bit of light too.

Lance B
22-07-2012, 4:15pm
As others have said, polarisers are probbaly one of the most useful filters that you can use and I always have one in my bag. The best thing for removing glare and reflections as shown by a number of photos here.