Polarizer for sunrise?

[desmond_cheung1]

<p>Hi,</p>

<p>I will be shooting sunrise at a lake this coming Saturday. I will have grads but I currently don't have any polarizer. At 16mm wide, should I get a polarizer? I have heard that for sunrise you don't need any polarizer and also at this wide angle, you will get vignetting.<br>

Any help is appreciated.</p>

<p>Desmond</p>

[jwallphoto]

<p>If you're going to get vignetting, it'll happen at any time of day. You can buy a thin-mount polarizer to reduce your chances of vignetting. But I wouldn't worry about using a polarizer for sunrise in any case. You've already got beautiful light at that time of day.</p>

[SCL]

<p>At sunrise, if you're shooting toward the sun, a polarizer won't have any polarizing effect. If you're shooting at 90 degrees from it, you will have an effect, but it may be overwhelming at that hour of the day.</p>

[stp]

<p>No, you won't need the polarizer. The polarizer has its effect as you face away from the sun, with the greatest effect at 90 degrees from the sun. There is no polarizing effect when facing directly toward (0 degrees) or directly away (180 degrees) from the sun. The effect of the polarizing filter gradually increases as you rotate from 0 (or 180) degrees to 90 degrees relative to the sun<br>

I'm fairly certain that what is meant by "vignetting" is actually differing degrees of polarization and therefore differing degrees of reduction of polarized light across the scope of sky taken in by a wide angle lens. IMO, polarizers and wide angle lenses simply are a very poor combination, because they usually end up with a sky that is very light in some portions and very dark in others, which I think looks terrible. The only place I would use a polarizer on a wide angle lens is in the interior of a forest when I'm wanting to reduce the glare on wet foliage and produce more saturated colors. When using a polarizer for the sky, I want to use a lens that takes in only a limited range of the sky; i.e., a telephoto lens.</p>

[lachaine]

<p>You may get vignetting when adding a "filter" with a thick ring on an extreme wide angle, but more importantly, you will likely get banding across the sky. Of course, if you're shooting at dawn, you won't need a polarizer. I doubt you will even need graduated filters.</p>

[desmond_cheung1]

<p>Thanks for all the responses. Looks like I won't need one :) </p>

[g dan mitchell]

<p>Actually the maximum effect of a polarizer is when you shoot at right angles to the sun - not towards or away from it. Bottom line: if you are shooting the sunrise/set itself the polarizer won't provide much benefit. (If you are shooting full frame, I suppose it is possible that the far edges of the frame could be close enough to 90 degrees from the sun that you might darken them somewhat...)</p>

<p>Dan</p>

[kris-bochenek]

<p>I shot sunrise few times and never used any filters. Results I got were pretty good. You can see some of the shots in my portfolio here at P.net. with filters you will get reflections.</p>

[david_henderson]

<p>Let's split the issue up.</p>

<ul>

<li>Do you need a polariser? If you take a lot of landscape/cityscape shots with blue skies the answer is yes. If you ever feel you want to reduce the reflectivity of water, leaves, glass etc then the answer is yes.</li>

<li>Do you need a polariser in the circumstances described? Probably not, depending on how long after sunrise you're planning to shoot, at what angle relative to the sun you'll be shooting , and whether you're using a wide angle lens that will create differentials in the degree of polarisation across the frame to produce an artificial-looking result. But then you should always decide to use a polariser or not on a shot-by-shot basis- its not something you use all the time. </li>

<li>Will you get vignetting? Some lens/filter combinations create vignetting. Vignetting is not the same as differential polarisation, its a darkening of corners created by the filter meachanically blocking light to the corners of the frame. Best to get a slim polariser to be sure. But the trade off is that many slim mounts don't have a front thread to attach another filter -which may not matter- or indeed to use a lens cap, which won't matter if you take the filter off after each shot or sequence.</li>

</ul>

[mountainvisions]

<p>Actually not true. While a polarizer might not have an effect on the sky, if you are shooting on water it will reduce reflections on the water in two ways. 1) actively 2) through longer exposure times.</p>

<p>Do you need one? No! but could one be useful? Possibly!</p>

<p>I do agree with the post above that on a wide angle lens it looks horrible if you have full effect where one part of the sky is darker than another.</p>