Luminous Landscape Forum
Equipment & Techniques => Cameras, Lenses and Shooting gear => Topic started by: ChristopherFrick on May 21, 2008, 08:54:31 pm
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Hello,
I had taken a series of snow shots during an overseas trip with my DSLR with only a UV filter. I had read prior briefly to leaving that using polarizers are not a good idea for snow scenes.
A lot of my shadows have a blue tinge which are a bugger to fix. I've used the Nik Skylight filter plugin but not to my satisfaction. Hence my goal is to get it right in the shot in the first place.
So really my question is if using polarizers and/or skylight filters for snow shots on a DSLR is practical? I've checked the net but the answers are ambiguous. I'd appreciate any comments from those experienced in snow shots.
Also is leaving a skylight filter on the lens ALL the time for ALL types of landscapes scenes (snow and non-snow) ok?
Thanks,
Chris.
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I always thought snow was a little blue.
Why not white balance it away?
Also is leaving a skylight filter on the lens ALL the time for ALL types of landscapes scenes (snow and non-snow) ok?
I don't know why you would. Putting anything in front of your lens increases your chance of flare.
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Why not white balance it away?
Putting anything in front of your lens increases your chance of flare.
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Thanks.
WB works to a degree but not to 100% satisfaction.
Flare! - I always shade my lens.
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The blue in shadow areas is really natural, it's just more obvious in snow scenes.
The only thing illuminating the shadow area is the sky and reflections from the surrounds. I would expect that the worst images you are dealing with were taken on very clear days. The sky is a deep blue and as there is no warm/yellow light falling in the shadows from the sun, so the cooler/bluer light predominates.
Our eyes adapt locally and very quickly so we don't "see" this, but the sensor can't do that.
When this is objectionable I fix it by selecting the shadow area only and colour balancing it separately.
Here are 2 examples, one semi-fixed, one not...
The 1st one had a horrible blue shadow on the back of the shell. I initially processed this file very quickly and made a print before I noticed it. this jpg version is semi-fixed, if you look at the original size you can see a blue tint in the deeper shadows, I fixed the rest of it and fixed i tall in my hi-rez tif for my final print.
http://www.pbase.com/mike_broomfield/image/76546980 (http://www.pbase.com/mike_broomfield/image/76546980)
In this 2nd one you can see the OOF blue areas in the back. They are gravestones that are in shadow. They are no different than the broken cross in the foreground, but as they were lit by the clear sky the sensor sees them as blue. I have another version of this in which I've fixed them but it's not uploaded.
http://www.pbase.com/mike_broomfield/image/65833541/large (http://www.pbase.com/mike_broomfield/image/65833541/large)
All of these were taken at sea level with no filters.
Hope this helps.
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Unless you mask and work on the snow separate from the rest of the image you will have to make a white balance compromise. The blue cast is normal for snow on sunny days and any attempt to adjust white balance globally based on the snow will throw your other colors out of whack.
Reminds me of my rant against the Red Lobster TV advertisment... there is this ad for the restaruant chain that features a bright red lobster running across the ocean floor. Only problem is that lobsters turn that color only after they've been cooked.
Dan Marguils also asks the question "what color should a white horse lying on a green lawn under the shade of a tree on a sunny day be?" Same issue.
In the end it's a creative decision... you have to decide whether to edit towards the ideal or the real.
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In this 2nd one you can see the OOF blue areas in the back...I have another version of this in which I've fixed them but it's not uploaded.
http://www.pbase.com/mike_broomfield/image/65833541/large (http://www.pbase.com/mike_broomfield/image/65833541/large)
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Hello,
thanks for the advise and I understand what you are all saying but it does not answer my original question regarding a Skylight filter. Would it negate and/or minimise any PS work.
BTW Mike, you're second example is password protected.
Regards,
Chris.
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Hello,
thanks for the advise and I understand what you are all saying but it does not answer my original question regarding a Skylight filter. Would it negate and/or minimise any PS work.
BTW Mike, you're second example is password protected.
Regards,
Chris.
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Chris
One theory is that over your sensor is an anti aliasing filter and a bandpass filter (UV+IR) so a UV filter over your lens is adding UV filtration to an already filtered image. So one would not place a UV filter over a lens for general purpose use. If you do want to protect your lens at the expense of flare Hoya makes digital protection filters that do not filter the UV. Hoya Pro 1 D protection (I think?) Most however leave the filter off and do not remove the lens shade.
On the issue of blue in your shadow I believe your mind removes this from a scene but the sensor captures it, so in PS select/color range and select the shadows then use curves/blue channel and reduce the blue cast until it looks like how you remembered the scene.
Hope this helps
Marc
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Password should be fixed now.
I think the answer is no. As I mentioned the photos I took were at sea level and with no filter, so this happens anywhere (although worse at high elevation and a deeper blue sky) and is due to visible light, not UV. Any PS technique you develop would be the same.
Mike