Air/Heat turbulence

[dalethorn]

Just wondering what people do when warm air turbulence disrupts a landscape pic. If the location is more-or-less always warm, could there be a way of combining images to reduce the "wavy image" effect, since I presume there's no coming back later?

[01af]

In theory, you can get a sharp image through turbulent air indeed by taking dozens or better hundreds of captures and then superimposing them in a clever way. However there is no post-processing software actually supporting this. You could write your own program (google for "ImageJ", for example) that runs a statistical analysis on each pixel across all captures and then paints that pixel in the resulting image according to some sophisticated algorithm. This should be able to get rid of, or at least reduce, the atmospheric blur. In practice, this would be very tedious to do, and you still cannot take satisfying results for granted. The degree of success would depend on many factors, among them the frequency of the turbulences, the magnification (focal length, distance), and how accurately the multiple captures are aligned with each other.

Generally, it's best to do telephoto landscape shots in the early morning, within an hour or so after sunrise, or when the sun breaks through the clouds right after a rain shower.

-- Olaf

[BernardLanguillier]

In theory, you can get a sharp image through turbulent air indeed by taking dozens or better hundreds of captures and then superimposing them in a clever way. However there is no post-processing software actually supporting this. [{POST_SNAPBACK}][/a]

If I am not mistaken, PS CS3 Extended has some capabilities that could be use to that end.

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However, the fundamental question is more, why do you want to get rid of those effects. They are an integral part of the landscape and be be very pleasing when captured well.

Cheers,
Bernard

[dalethorn]

The actual image that prompted this (that I should have posted) has landscaping machinery sitting across a field about 200 yards away.  The natural elements of the image are OK, but the machinery just doesn't look right to me.  I don't doubt that getting the photo early or late would help, but on warm days, not enough.

[spclark]

What you're describing is commonly referred to as "mirage" and will be present any time the sun is heating the air nearest the ground, causing it to rise.

Any amount of wind will cause images taken through this movement to be distorted to a greater degree as the turbulence effect increases from the additional air movement. The longer the focal length of lens used the greater the evident distortion also.

On cloudy days mirage isn't as significant. Too, when the wind is really blowing the turbulence may not be as obvious if your exposure time can be extended.