Basic image adjustments for landscape photos

Hello Pritch,

I would recommend to adapt the camera to high altitude conditions, rather then to do too much post processing.

Pritch wrote:

I am at a high altitude, and many of my pics are bright and sometimes a little washed out. I use Auto Contrast sometimes, but then it sometimes goes too far, and appears too dark.

There are three scattering effects that do influence pictures at high altitudes: Rayleigh scattering, caused by scattering of the molecules of the atmosphere that tints the pictures blue, Mie-Scattering and non-selective scattering from small particles (pollen, dust, fog) that makes them appear hazy and washed out. The amount of corruption depends on the meteoroligal conditions, only the Rayleigh scattering is always present.

At what altitude are you? Do you know, if the CCD-Sensor in your camera blocks UV-light completely (some Sony sensors do) or lets some of the UV pass? If the latter were the case, then you will notice quite a lot of Rayleigh-scattering from blue and UV light turning your pictures blue at high altitudes, and you might consider to use a Skylight filter or even an UV Filter; in lower terrain that usually is unnecessary, since the lens absorbs most of the UV.

For landscape photograpy the filter should be a flare less one, otherwise the lens flare will spoil the picture.

And - if you do not do it already - correct the white balance at the time you take the picture, the default white balance settings of the camera usually are optimized for lower terrain.

To correct the effects of Rayleigh scattering after taking the picture you have to adjust the colors selectively to dim the blue, depending on the amount of additive blue in the picture. A white balance correction might do that if you are lucky.

The Mie scattering and non selective scattering reduce the contrast and dim the colors by adding white to the picture. To compensate them you would need a white-subtraction filter (not white balance), Aperture does not have it.

But you can achieve quite good results with a combination of black point correction, enhance definition, enhance contrast, and a slight increase of saturation. I cannot recommend default settings for these filters, because the amount of correction needed will depend on the meteorological conditions. Also, you may not want to remove the haze completely, because it will give depth to the picture and might be artistically pleasing.

A nice example on how to deal with haze is in this thread

Regards

Léonie

Wow, Leonie, nice explanation, I would consider adding a polarising filter to the mix as well.

Tony

Tony Gay wrote:

Wow, Leonie, nice explanation, I would consider adding a polarising filter to the mix as well.

Tony

Yes indeed 🙂.

Léonie -- thanks. The final link ("this thread") isn't working for me. Not just fyi -- I'd like to read that thread.

Cheers.

Kirby and Tony, thanks for the compliments - you made my day 😊

Kirby Krieger wrote:

Léonie -- thanks. The final link ("this thread") isn't working for me.

How come? I definitely remember checking the link? 😢

I meant the thread onhazy sentimental pictures - https://discussions.apple.com/thread/3348553?answerId=16237869022#16237869022

you know it well, you contributed to it. I liked the results presented by Ernie Stamper and azdawg99, and also Frank Caggiano's suggestions.

Cheers

Léonie

Definitely agree with all of the above. I especially liked the suggestions of dealing with this in the camera rather then waiting for post processing to try and fix it. Cutting haze or glare is much better done in the camera, almost impossible to do well after the fact.

And a definite +1 to the polarizing filter suggested by Tony. Nothing pops a color image especially the sky like it. And it's the only way to deepen the sky without changing other color values.

Doesn't it depend on how wide the angle of the lens is? Super wide angles can show the darkening *and* lighteneing effect of the polarizer.

Frank Caggiano wrote:

And a definite +1 to the polarizing filter suggested by Tony. Nothing pops a color image especially the sky like it. And it's the only way to deepen the sky without changing other color values.

I agree, polarizing filters are perfect to control the amount of scattered light when you take the picture. I only hesitated to recommend it, because the combination of CCD sensor and polarizing filter might be tricky to handle if the sensor itself has a strong polarizing effect. Then only circular polarizing filters might work. And at great heights, above the clouds, you might not need a polarizing filter to deepen the blue of the sky - it is stunning blue all on its own. This picture was taken at an altitude of 3300 m in Tibet, without a polarizing filter, and nobody believes me ...

Circular polarizers are required due to the phase-sensitive auto-focus. I don't think it has anything to do with CCD's. (Most current DSLR's are CMOS anyway.)

You are right - I was thinking of our first experimental fix focus CCD camera ... no auto focus and still needed a circular pol-filter ..

Doesn't really matter, as long as they get the take-away: Use a circular polarizer! 8^)

Keith Barkley wrote:

Doesn't it depend on how wide the angle of the lens is? Super wide angles can show the darkening *and* lighteneing effect of the polarizer.

Did you mean to write that super wide angle lens can't show the effect as well as normal or telephoto lens?

That I could see or am I missing something?

According to the Hoya site they recommend circular polarising filter unless you have a manually focusung camera.

See PL/PL-Cir

http://www.kenrockwell.com/tech/filters.htm

It shows the darkening and lightening *at the same time.*

Scroll down to "don't use a polarizer with a wide angle lens"

The effect of the polarizer only works over a 45 degree angle, outside of that it starts to fade. (which is why you have to rotate it, after all.)

Pritch wrote:

It is such a challenge to try to properly expose both the bright sky and the foreground.

You will need a correction method that works selectively on the foreground and background - auto exposure treets all pixels the same.

• I frequently use the "Highlights and Shadows" adjustment - that leaves the midtones as they are. With these sliders you can tone down the bright sky and lighten the shadow regions to reveal more detail .
• And if your foreground should be really close to you (e.g. a person standing in front of you) you might consider to use a flash to lighten the foreground, even on a bright sunny day.