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Thread: Filters

  1. #1

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    Filters

    Can anyone please let me know if using a circular polarised filter would help for snowy conditions? I have taken a few photographs this winter and they seem really too white and light - if that makes sense!

  2. #2
    DanK's Avatar
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    Re: Filters

    A polarizing filter will reduce glare. My guess is that your problem is exposure, not the lack of a filter. Your camera is taking the scene (which portion depends on the metering mode) and metering it for neutral gray, so you will overexpose snowy scenes. Try setting an exposure compensation of -1. If that does not suffice, try -2. Or use a spot meter and meter off something other than the snow--e.g., meter off the palm of your hand and then open up one more stop.

  3. #3

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    Re: Filters

    Quote Originally Posted by DanK View Post
    Your camera is taking the scene (which portion depends on the metering mode) and metering it for neutral gray, so you will overexpose snowy scenes. Try setting an exposure compensation of -1. If that does not suffice, try -2.
    You've got the concept partially correct, Dan. You're right that the camera meter will read the snow as neutral gray in many situations. To correct the rest of your statement, the result will be underexposure and you will need to use a +1 to +2 exposure compensation.

  4. #4

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    Re: Filters

    Quote Originally Posted by Andybazyoung View Post
    Can anyone please let me know if using a circular polarised filter would help for snowy conditions? I have taken a few photographs this winter and they seem really too white and light - if that makes sense!
    The circular polarizer will not address that issue though it can address other issues that occur in snowy conditions. Your best bet is to post a sample photo that displays your problematic issues so we know what to suggest to do in the future.

  5. #5

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    Re: Filters

    Polarizers can help with bright conditions, Andy, but subject to how you use them. They will darken everything but in most conditions I prefer to get the exposure correct instead of a polarizer. As previously mentioned.

    So I would spot meter around the scene to find the brightest area then adjust for that. Evaluative metering often misses some bright spots.

    It is true that this will give you a slightly off white and a little positive exposure compensation is required to produce pure white. But in most cases, I am happy to err slightly on the under exposure side then recover any darker areas during editing.

    You can use Evaluative Metering and just tweak the compensation a little as you estimate the scene brightness, which can be handy for those quick shots in variable brightness. But this is something which comes with experience; spot metering will give exact readings.

    However, living a little bit south of you, on the coast, snow is something of a rarity; however I use the same technique for seascapes which include white boats, etc.

  6. #6

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    Re: Filters

    Quote Originally Posted by Geoff F View Post
    Polarizers can help with bright conditions, Andy, but subject to how you use them. They will darken everything but in most conditions
    I think I understand what you mean, Geoff, but I think the statement on its own is misleading to anyone who hasn't used a polarizer. The polarizer is in effect a neutral density filter when it is not addressing polarized light. In that situation, it only allows less light into the lens, in which case the camera's meter will compensate by requiring the use of a slower shutter speed, larger aperture or both.

    My point is that if I am photographing a snow scene or a beach scene, the same exposure compensation, if any, will be needed whether or not I'm using a polarizer so long as polarized light is not being attended to by rotating the polarizer.
    Last edited by Mike Buckley; 6th March 2013 at 12:54 AM.

  7. #7
    DanK's Avatar
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    Re: Filters

    Quote Originally Posted by Mike Buckley View Post
    You've got the concept partially correct, Dan. You're right that the camera meter will read the snow as neutral gray in many situations. To correct the rest of your statement, the result will be underexposure and you will need to use a +1 to +2 exposure compensation.
    Oops. thanks for catching the careless error.

  8. #8
    William W's Avatar
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    Re: Filters

    Quote Originally Posted by Andybazyoung View Post
    Can anyone please let me know if using a circular polarised filter would help for snowy conditions?
    Yes in many situations a CPL Filter (Circular Polarizing Filter) will be useful in Snow: and also in other glare conditions, such as on the water.

    ***

    Quote Originally Posted by Andybazyoung View Post
    I have taken a few photographs this winter and they seem really too white and light - if that makes sense!
    From what you have described, yes, possibly a CPL Filter will assist you.

    Whilst a sample photo or two would be very beneficial to better identify the issues and make for a better answer. - you specifically state that a few of the photos “they seem really too white and light”,

    This implies that most of your images are not too white and not too light and therefore, probably correctly exposed.

    Also, if you were not understanding the metering system of your camera and this was the cause of THIS problem, you would probably describe the problem as your images being “too grey and too dark” (because the metering would be UNDER exposing the snow).

    So it occurs to me that it is more likely that you have a General GLARE which is interfering with some of the lens elements and possibly causing Veiling Flare and or General Lens Flare resulting in a general white milky cloudy appearance (Veiling Flare) or areas generally which appear to be ‘too white’ (a result of general lens flare).

    In these cases a CPL may assist you.

    Other remedies addressing the problem of Veiling Flare and General Lens Flare are:

    Remove (protection) Filters
    Use a smaller rather than larger Aperture
    Use a Lens hood
    Use a Prime rather than a Zoom
    Be aware of the angle of the Sun and also the angle of DIRECT reflections from the sun and use elements of the scene to shield the lens from those direct light rays.

    WW
    Last edited by William W; 4th March 2013 at 01:31 AM.

  9. #9

    Re: Filters

    I think the benefits you will gain by using the polarizing filter is that it will make the blue sky look better and reduce the distracting reflections from other shiny objects. And you've mentioned that that the snow is too white, I think you're on the right track, you just need to underexpose a bit until you get the image that you want. For more tips, visit my blog: http://shootdigitalpicslikethepros.c...-forum-support

  10. #10
    Moderator Manfred M's Avatar
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    Re: Filters

    First of all, you must be doing something right if your snow exposures are coming out too light. The light meters in most cameras result in gray looking snow as the camera’s exposure algorithms assume a 18% neutral gray scene, hence the need for exposure compensation.

    Shooting is snow is a tricky thing to do as you are effectively using a giant white reflector that bounces ambient light everywhere. On a bright sunny day this means harsh shadows and on a cloudy day you get very diffuse light that can give you results that range from boring to downright beautiful, depending on the subject matter (hint: not great for landscape shots, but is wonderful for wildlife and the animal’s fur is well lit).

    Even though I live somewhere with lots of snow for four or five months a year, I still end up having to be very careful when I start shooting and will take a number of test shots to get a good understanding as to what the light is doing in a specific composition. There are shots that require no exposure compensation (just because you are shooting a scene with snow doesn’t mean that you are not close to that 18% gray average, especially if you are doing a close crop on a subject). On the other hand, if there is a lot of snow in the scene, depending on the amount of light exposure compensation of +1 (overcast) to +2 (bright sunlight) can be required. I do watch my histogram when I and doing my test shots to ensure that I have not blown out the highlights (which is all too easy to do). One has to be a bit careful here too because your histogram will show a large spike at the right and as long as you are not all the way to the right, this is fine; snow is white and there should be lots of white pixels. As long as there is a bit of headroom there and you have not blow out the highlights, you will be fine.

    Polarizers will do what others have written and can reduce glare even on a cloudy day, but your in camera metering will compensate for the additional exposure required (typically 1.5 or 2 stops) automatically, so the exposure compensation adjustments will continue to be an issue.

    Another issue that you will be fighting when you shoot snowy scenes is that our eyes tend to key in on the highlights, so it can be a bit difficult for the viewer to focus in on the subject. We often use a vignette around the edges of the image to help direct the viewer’s eyes, but we risk making the snow look too grey when we do this.

    Assuming that you have done everything correctly and you are exposing properly, there are still going to be some issues that you will be fighting when shooting in the snow:

    1. I find I will shoot at as low an ISO as I can with my camera; low ISO means high dynamic range, within the capabilities of your sensor.

    2. With the snow acting as a large white reflector, there could be very minimal difference in the shading, so you can get large areas that are very light. You might be able to pull this out in PP, but this is not always possible, because it can be too easy to get grey looking snow, and no discernable highlights. This is the problem that I ran into with this shot; a large wide open field with minimal shadow detail. Trying to get detail (and having the snow still look somewhat white) and show the correct exposure for the bison is tricky. I made life even more difficult for myself by trying to put in a vignette to downplay the bright background in the corners.

    This shot has a +1EV exposure compensation, and was shot under a very overcast sky, no filter used on this shot.

    Filters



    3. This is an example of a shot where I did not need any exposure compensation, because, while there is snow in the scene, there is enough other material and the exposure meter was able to read the shot properly. Another shot with no filter.

    Filters


    4. In this shot, the low ISO (100) was able to pick up some of the shading on the snow. I used Nik Color Efex2 to post-process this shot to enhance the shadows a bit to provide a bit more dimensionality to the snow. I used +1EV in this shot and just like the previous one I have a slight vignette to focus the viewers eyes on the deer. Again, so filter used on this shot.

    Filters



    5. In this scene, we see another issue with snowscape shots. Instead of fighting the dull overcast light, in this scene I was shooting on a bright sunny day, just after 9:00 in the morning. The scene was shot without exposure compensation.

    Here we have the harsh shadow problem, which can be problematic for people shots. Fortunately, I was able to position myself to take advantage of the direction of light. The skier’s faces are nicely lit, and the harsh shadows fall behind them. The shadows have that typical blue cast we get in snow scenes. I suppose I could have desaturated them in PP, but if you look closely, they actually do have a blue cast.

    Filters



    6. This is a sunset shot, literally moments before the sun dipped below the horizon, and here we get some funky mixed lighting. The highlights have that yellow-orange cast that we know from sunset shots, but once you get into the shadows, the blue cast pops out.

    This is just a typical mixed lighting issue, but frankly I think it works in this image as the blue shadows nicely balance the blue winter sky. This shot was done with a circular polarizer and I was shooting at 90° to the direction of the sun (which was setting camera left). No exposure compensation in this image and shot using a tripod and slow shutter speed (1 second) to slow the rapidly flowing water over the falls.

    Filters


    I hope that this gives you a bit of an overview on photography in snow; filters, polarizers, etc....

  11. #11

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    Re: Filters

    Thank you all so much for your thoughts. They will, I am sure, be very useful when we get snow again!

  12. #12
    Moderator Manfred M's Avatar
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    Re: Filters

    Quote Originally Posted by Andybazyoung View Post
    Thank you all so much for your thoughts. They will, I am sure, be very useful when we get snow again!
    Would you like some of ours? I would be more than glad to have someone take it away...

  13. #13

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    Re: Filters

    Thank you Manfred. Just only to chill my G&T would be nice!!

  14. #14

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    Re: Filters

    Wonderful examples, GrumpyD. Picking up on your description of snow cover s being a "giant reflector", this can be used to one's advantage. For example, on a sunny day in the summer, a photo of a person's face might have one side in shadow where one has to use a fill in flash to solve that issue. In the snow, the giant reflector can be used to bounce light onto the side of the face that might otherwise be in shadow. So, next time you take a portrait out in the snow on a bright sunny day, have the sunlight hit the face from a side angle!

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