Do I need a polarizing filter?

[j_john1]

<p>I have been reading all the good things about having a polarizing filter. Wonder if the same effect can be achieved using software like Adobe photoshop. I would rather invest in software.<br>

I am planning on a Alaska trip and would like to know if I would need to use polarizing filters when shooting whales, icebergs etc.</p>

[Matt Laur]

<p>Out on the water, a polarizing filter can cut down on glare and reflections. If you get a lot of such reflections as you're shooting, there's nothing that PS can do to remove them after the fact.</p>

[jim_momary]

<p>You will have lots of sun/sky reflection/glare off the water. That glare will interfere in your attempt to record other stuff in the image. Therefore, pretty much, you will not have anything that's fixable later.</p>

<p>As far as I know, the effect of polarization is best done in camera and cannot really be equalled by any other post process. Remember tho, max effect is at 90 degrees to the sun and very wide angle lenses will show a graded sky, as the image may cover beyond the polarized area</p>

<p>Jim</p>

[iliafarniev]

<p>If you are intend for images with aesthetic appeal, especially nature shots, you have to use <strong>quolity POL filter</strong>. There is no software substitute even you shoot in cloudy or foggy weather.</p>

[j_john1]

<p>Thanks for the quick responses. In that case what would you suggest I buy. CPL with single coated or muti coated. Which brand....Hoya, Tiffen. I want one for my 18-200 lens on D300s.</p>

[Alan Marcus]

<p >Likely, the most popular filter is the UV and its cousin the Skylight. Both reduce atmospheric haze due to water vapor that scatters UV light. Films and digital chips are sensitive to UV however; these filters are overrated, they only work on distant landscapes and at high altitudes. Mostly they line the pockets of the sellers who taunt to buy and mount to protect our valuable lenses from scratches etc. </p>

<p >The polarizing filter also cuts haze as it darkens the sky inducing vivid blue against white clouds. The polarizing filter is a must for your gadget bag. It is the only filter that can mitigate reflections from glass and water and other non-conductive surfaces. You cannot exactly duplicate this effecy via software. </p>

<p >Some modern cameras use polarizing filters in their exposure sensor and focus sensor systems. If your camera has such systems, mounting a polarizing filter will do harm. These "straight" polarizer's are now called linear. Nowadays we mount "circular" polarizing filters. These are sandwiched filters. The front filter effectively does the polarizing so we get the full photo effect. Once the deed is done, the second filter called a corrector, de-polarizes avoiding problems with the camera's sensing mechanism. </p>

[steve_levine]

<p>The effects of a pola filter, is one of the few things that cannot be replicated, "post shooting" via soft ware. Many photographers use one outdoors at all times for landscapes etc. They increase contrast, and color saturation, by eliminating scattered (polarized) light. The difference can be seen in the VF when you turn the filter's ring.</p>

[nodpete]

The only thing I would add is to get in the habit of turning the filter counter-clock wise ( when focusing the camera) so you don't accidentally unscrew it ! I've seen that happen!

[paddler4]

<p>John J</p>

<p>Actually, linear filters are sandwich filters too, so don't use that as a guide. The filter should be listed specifically as a circular polarizer. I think multi-coated is better, to reduce glare. I wouldn't consider uncoated. I use Hoya multicoated myself.</p>

<p>Dan</p>

[CoryAmmerman]

<p>Darkening the sky and adding contrast can be done in post, but it's sometimes harder to get it to look right than using a polarizer. You can't do anything to cut glare in post. The only bad thing about polarizers is the 1-2 stop light loss, but sometimes that can be handy too if a longer exposure is what you're after. Another word of warning, since the effects of the CP depend on your angle relative to the sun, with really wide angle lenses, the effects will be uneven from one side of the frame to the other. Personally, I have a Tiffen CP that I bought several years ago. I haven't noticed any image degradation when I use it.</p>

[johnw63]

<p>Just don't go cheap on the filter. I've seen really odd colors due to cheap filters. I think you can find some on youtube. I don't think that means you MUST go high end. Just don't go bargain basement.</p>

<p> </p>

[bob_bill]

<p>If you are shooting vegetation, it too can become less saturated because of the glare off its surfaces. Agree with Cory re the 2 stop loss, trying to blur water, moving vehicles, people, you are at least part way there without a neutral density filter. One of the advantages of Nikon pro lenses is they take 77 mm filters. so one polarizer or softar fits all. </p>

[mariosforsos]

<p>Having travelled to Iceland recently, I would definitely advise you to get a high quality CPL filter (brand is really not an issue - they are equally good). Very few of the results of a CPL can be immitated or replicated using software - save perhaps some colour saturation under SPECIFIC conditions. It's quite possibly the most useful filter you'll have in your bag.</p>

<p>True, it may cut off a bit of light, but your D300s has more than enough sensitivity latitude to take it in its stride - just crank up the ISO slightly when faced with challenging light conditions.</p>

<p>One thing you need to remember however: you will need to adjust the filter's setting every time (I've seen people setting it once and then assuming it'll work all the time), even if you take a step to the right or to the left...;-)))</p>

[mart_e]

<p>As Jim mentioned - polarizing filters do not add a consistent effect.</p>

<p>They are most effective when the light is reflected at 90 degrees from source to lens - and least effective when reflections are at 0 or 180 degrees.</p>

<p>Their effect therefore varies depending on the lens / situation. ie for wide (and particularly ultra-wide) lenses where you are seeing a huge portion of the sky / water etc. the effect of the polariser will vary from strong to minimal within the same frame - as the angle of reflected light changes.</p>

<p>You may therefore find that you still need to resort to PP to correct/alter an image that you shot with a polarizer to get some consistency across a frame, or across a number of shots taken from different positions / view relative to light source.</p>

<p>Not sure whether it is just me, but the effect of a polariser seems less with digital than with film - maybe that's just me comparing rich Velvia skies on film with the digital counterpart.</p>

<p>Martin</p>

[JDMvW]

<p>+whatever on a polarizing filter being<br /> 1) one of things that cannot be done after the fact. At best you can only clone over reflections and cannot recover what was actually behind/under the light reflections.<br /> 2) one of the essentials of a complete camera kit<br /> 3) does not work all that well with super wide lenses because the effect is dependent on the angle of the camera in relation to the sun<br /> 4) this is one case where buying a good, multicoated filter is essential. A cheap polarizer is not worth too much, certainly not what you would have to pay for it. On the other hand, there are some small company specialty versions that are over priced. I think the MC Hoyas are probably the minimum you should settle for.<br /> 5) you can save money by buying the polarizer in the largest size lens diameter you have and using step-up rings to adapt it to the smaller diameter lenses. The catch? You may not be able to use the adapted filter and the lens hood at the same time, only experimentation will tell. You do NOT want to shoot with any filter without a lens hood as a general rule.</p>

<p>oh- and it's much better to use circular polarizers these days, as things may not work exactly right with the older linear ones.</p>

[ljwest]

<p>As others have mentioned, the two things that cannot be replicated in any software are glare reduction and reflection reduction/elimination.</p>

<p>Light reflecting off of water, glass, painted and other surfaces becomes polarized. That is, all the light waves are paralell to one another. A PL filter enables you to cancel polarized waves on a particular axis, and pick up the waves reflecting on a different axis.</p>

<p>I'll give you an example of where the PL filter was indispensable: I was at a car show, and one car had a gorgeous black paint finish. On the hood, there was a mural painted. With the sun angle, and intensity, it was very difficult to make out the mural, even with the naked eye. but the PL filter, duly twisted to the proper angle, eliminated the reflection, enabling me to get a picture of the mural clearly with my film camera. My digital, without benefit of the PL filter, picked up just the glare.</p>

<p>Other examples include: taking photos of wildlife under the water (not to be confused with underwater pictures) from above the water; getting a picture of something behind glass, say a department store window display on a sunny day.</p>

<p>You can't fix any of these things in a computer program, simply because the image information isn't there. The glare or reflection overpowers the image you want on the film or sensor.</p>

<p>Most film cameras, and some digitals can use the "Linear" polarizing filter. A few film cameras, and most digitals require a "circular" polarizing filter, due to the autofocus and other sensors inside the camera. What I find interesting is the new "Circular" polarizers are really a linear polarizer (which reduces glare and reflections), sandwiched with a circular polarizer (which keeps the sensors happy).</p>

<p>Read more about it at <a href="http://en.wikipedia.org/wiki/Polarizing_filter#Circular_Polarizers">Wikipedia</a>.</p>

[nathangardner]

<p>Without even reading the post, YES! I did read the question, but as soon as I saw the topic my answer was yes. A polarizer is one of the only filters that is still necessary with digital photography. Most other filters are becoming extinct because they can be reproduced in photoshop, but a polarizer cannot. Look on ebay, there are some good deals on good filters. And remember, you get what you pay for. You don't want to put a cheap piece of glass in front of an expensive lens. I got a new Hoya Pro1 D polarizer on ebay for $90, it retails on B&H and Adorama for around $165. Just do some research to figure out which one you want then look for a good deal. You will most likely have to buy online since filters are becoming obsolete and stores have a very scarce selection.</p>

[steve m smith]

<blockquote>

<p>oh- and it's much better to use circular polarizers these days, as things may not work exactly right with the older linear ones.</p>

</blockquote>

<p>Linear polarisers are fine on all of my cameras.</p>

 

<blockquote>

<p>A polarizer is one of the only filters that is still necessary with digital photography. Most other filters are becoming extinct because they can be reproduced in photoshop, but a polarizer cannot.</p>

</blockquote>

<p>True. I would put neutral density gradient filters on the list of must have/can't really be done in post processing filters too.</p>

[mwtphoto]

<p>if you do landscape photography the hoya moose filter is excellent. it is a combined circ pol with a 81a warm up filter. the pol may add a blue hue to foilage so the warm up filter brings the green back. Lightroom has a neutral gradient filter feature so polarizing is probably the only thing that can't be done in post processing.</p>

[steve m smith]

<blockquote>

<p>Lightroom has a neutral gradient filter feature so polarizing is probably the only thing that can't be done in post processing.</p>

</blockquote>

<p>It does but once you have blown out the highlights in the sky, nothing you do in post processing will bring them back again. Better to get it right to start with and ND grads are the way to do this.</p>

[j_john1]

<p>I was looking for multi coated Hoya and found this nikon filter on ebay, would you recommend I buy instead of a Hoya:<br>

<a href="http://cgi.ebay.com/Genuine-Nikon-72mm-Circular-Polarizing-Filter-New-rare_W0QQitemZ130271333575QQcategoryZ15217QQcmdZViewItemQQ_trksidZp4340.m8QQ_trkparmsZalgo%3DMW%26its%3DC%26itu%3DUCC%26otn%3D20%26ps%3D63%26clkid%3D8605099972397547899">http://cgi.ebay.com/Genuine-Nikon-72mm-Circular-Polarizing-Filter-New-rare_W0QQitemZ130271333575QQcategoryZ15217QQcmdZViewItemQQ_trksidZp4340.m8QQ_trkparmsZalgo%3DMW%26its%3DC%26itu%3DUCC%26otn%3D20%26ps%3D63%26clkid%3D8605099972397547899</a></p>

[dan_south]

<p>A circular polarizer would be useful on your trip, but be sure to PRACTICE with it before you go. Like any other effect, polarizing filters can make some images look worse rather than better.</p>

<p>Here are some polarizer caveats that you should take into account.</p>

<p>(1) Shutter speed - A polarizer will slow your shutter speed by up to two stops. 1/60th of a second now becomes 1/15th (too slow to hand hold or stop action).</p>

<p>(2) Unnatural skies - On a hazy, sunny day the polarizer can darken the sky dramatically. Some darkening can look okay, but if you go too far the effect might ruin the shot. Also, sunlit objects will be much brighter than your very dark sky. This can cause unintended exposure problems.</p>

<p>(3) High altitude - Skies are already dark blue at high altitude. Adding a polarizer could make them look ridiculous.</p>

<p>(4) Light falloff with wide-angle lenses - The polarizer has a more pronounced effect on wide-angle lenses. You'll see the sky get darker and darker as you move farther from the center of the lens.</p>

<p>(5) Vignetting - As with any filter, the polarizer might darken the corners of your images when used with some lenses or at the more wide open f-stops. It's important to know how the filter works with each of your lenses before you embark on a once-in-a-lifetime trip.</p>

<p>(6) Too much contrast - In some lighting conditions and for some subjects, polarization just doesn't look very nice. Experience will teach you when to lessen the filter's effect (by rotating its ring) or when to avoid using it altogether.</p>

<p>Remember, TRY before you FLY.</p>

 

[raymondborg]

<p>I suggest you don't go photographing the whales without a polarizing filter. It will take off the reflections when photographing on the water. Better get it right from the start then spending a lot of time in front of your pc, trying to correct things that you should shot correctly from the start. Congrats.</p>