There has been some discussion of late concerning atmospheric compression. One user was told by a "dealers" that he absolutely did not want a 500mm lens because the "atmospheric compression" would not allow him to ever take a sharp picture with it.
Atmospheric compression is a natural phenomenon that does occur with long telephoto lenses and the user needs to be aware of the issue itself as well as the conditions that cause it. Things like hazy shy conditions, blowing dust, high humidity and high air temperatures all are causes of atmospheric compression. High noon on a windy day is usually a killer for sharp images with a long lens.
I was out in the Pryor Mountains today observing the wild horses there when I realized the atmospheric compression issue was at its peak on this 90 degree day with winds blowing close to 30 mph at the time causing dust to be carried aloft all over the place.
I decided to set up my 800mm F5.6 lens (not much more compression available than with this lens) and a full frame body to take some shots and see if I could get a sharp image as well as demonstrate atmospheric compression issues. At first the sky was also very smoky from the Washington state wildfires, but as time went on the shy cleared up and actually offered some decent light to work with.
I shot the stallion below as one of my very last shots. On the download you will be able to see his mane hair blowing in the wind as well as his "battle scars" earned from fighting for breeding rights. If you look close you will also see some flies buzzing around his snout. This stallion was at about 260 feet from me and I have to say he came out nice and sharp for the conditions presented.
Now, take a look at the brown mare in the background. True, the DOF has her blurred out, as intended, but she was over 500 feet away from my camera and if you look at the image at 100% or above you will clearly see the distortion caused by the atmospheric compression. The effect was minimized by the fast shutter speed, but the extra distance and out of focus element cause the effect to be pronounced.
I am not offering this image up for critique (but I happen to like it) but am simply posting it as a demonstration of the effect and how it will show up on images even used with the best of technique. For best telephoto results always use a tripod, try to avoid windy days, and shoot early in the day when the air is usually the cleanest.

Wednesday May 28th, 2014 informationliberation.com
American Soldiers Did Not Die Defending Our Freedom (Jacob G. Hornberger)

I was at the Washington Nationals baseball game yesterday. Whenever I attend a Nats game, there is an air of militarism surrounding the game, but attending on Memorial Day helps to remind us what a truly militarized society America has become.

After all, what in the world does baseball, a quite peaceful and enjoyable pastime, have to do with America's countless foreign wars, which have killed, tortured, and maimed millions of people?

One of the most fascinating aspects to U.S. militarism is the bromide that has infected the minds of so many Americans: that U.S. soldiers have sacrificed their lives or limbs in foreign wars to "defend our freedom" here at home. Not surprisingly, it was repeated at the Nationals game yesterday. People who came to watch a baseball game were asked to remember the sacrifices, including deaths, that American servicemen have made in the "defense of our freedom."

Why do I find that fascinating?

Two reasons: first, The bromide is palpably false, and, second, it is a testament to the power of state to indoctrinate the citizenry.

This is a bromide that is inculcated into every child, from the time he reaches six years of age and heads into the public (i.e., government) school system. By the time the kid reaches his teen years, the indoctrination is taking hold. By the time he becomes an adult, the indoctrination is complete. In fact, the indoctrination is so perfect that actually it doesn't matter what the troops are doing overseas. Whatever they are doing is automatically considered to be "defending our freedom."

Consider a hypothetical. Suppose there is some country thousands of miles away that is minding its own business. There are no attacks on the United States or even threats to attack the United States. The only problem is that the regime is not sufficiently submissive to the U.S. government.

The U.S. government decides to invade the country and install a pro-U.S. regime. The troops are sent into battle. Some are killed. Countless more people are killed on the other side.

There is no doubt that millions of Americans will automatically conclude that those U.S. troops killed and died "defending our freedom," notwithstanding the fact that our freedom was never at risk. Remember: that hypothetical country never attacked the United States or even threatened to do so. Yet, many Americans will nonetheless honor their brave and courageous soldiers who died or lost arms or legs while "defending our freedom." It is how the indoctrinated mind works.

How can I be so certain that that's the way many Americans would react to that hypothetical situation?

Because that's what happened with Iraq, a country whose government never attacked the United States or even threatened to do so. Thus, not one single U.S. soldier died in Iraq "defending our freedom" because our freedom was never threatened by Iraq.

The same holds true for the 58,000 plus American soldiers who died in the Vietnam War. North Vietnam was engaged in a civil war against South Vietnam. At no time did North Vietnam attack or invade the United States. It had no interest in doing so and, anyway, it lacked the military capability to do so. The U.S. government invaded Vietnam and embroiled itself in its civil war. At no time were the freedoms of the American people threatened by the North Vietnamese. The American troops who were sent to the deaths in Vietnam did not die in the defense of our freedom here at home.

The same is true for the tens of thousands of American men who were sent to their deaths in the Korean War. North Korea never attacked or invaded the United States or even threatened to do so. American freedom here at home was never threatened. Thus, those U.S. soldiers in Korea did not die defending our freedom.

What about the soldiers who died in the U.S. invasion of Panama or Grenada? Again, Panama and Granada never attacked the United States or even threatened to do so. Those troops did not die in the defense of our freedom.

World War I? At no time did Germany or Austria-Hungary attack the United States or even threaten to do so. The Great War was a war between empires, one that never endangered the freedom of the American people. The U.S. government simply chose to intervene in that conflict in the hopes of "making the world safe for democracy" and to "end all wars." Those U.S. soldiers who died in World War I did not die defending our freedom.

What about the so-called "good war"--World War II. While Japan attacked U.S. forces at Pearl Harbor and the Philippines, the attack was a direct consequence of President Roosevelt's repeated attempts to induce Japan to attack the United States to fulfill his wish to get the United States into the war. FDR had imposed an oil embargo on Japan, frozen Japanese bank accounts in the United States, and imposed humiliating terms in pre-war negotiations with Japan, all with the aim of getting Japan to "fire the first shot" so that the United States could get into the war. Japan never had the aim or the military means of invading and occupying the United States and depriving the American people of their freedom.

What about Nazi Germany? It desired to avoid war with the United States, which is why FDR used Japan as a "back door" to war. The only reason Germany declared war on the United States after Pearl Harbor was to fulfill its treaty obligations to Japan. Before England declared war on Germany, it was clear that Hitler was moving east toward the Soviet Union, not west toward the United States. Moreover, since Germany lacked the military means to cross the English Channel and invade England, how in the world would it cross the Atlantic Ocean and invade the United States?

Moreover, consider the aftermath of World War II: East Germany and Eastern Europe and China all under communist control. Isn't that what American soldiers actually died for--so that the communists, rather than the Nazis or Japanese, could control those parts of the world? Even if one finds that a worthy thing to die for, it's a far cry from dying in the defense of our freedom here at home.

Oh, I almost forgot Afghanistan. No, al-Qaeda was never going to invade and occupy the United States and take away our freedom. Neither was the Taliban. The 9/11 attacks were retaliation for actions taken by the U.S. government in the Middle East prior to 9/11. The Taliban government never attacked the United States or even threatened to do so.

The truth, as discomforting as it is, is that the many U.S soldiers who have been sacrificed in America's countless foreign wars did not die defending our freedom. That's nothing more than a false bromide used to justify America's never-ending foreign wars.

When enough people break through the indoctrination, as libertarians have, the bromide will no longer have the power it does over people's minds. At that point, maybe Americans will be free to enjoy baseball games and other sporting events without all the militarism attached to them.
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Jacob G. Hornberger is founder and president of The Future of Freedom Foundation. He was born and raised in Laredo, Texas, and received his B.A. in economics from Virginia Military Institute and his law degree from the University of Texas. He was a trial attorney for twelve years in Texas. He also was an adjunct professor at the University of Dallas, where he taught law and economics. In 1987, Mr. Hornberger left the practice of law to become director of programs at the Foundation for Economic Education. He has advanced freedom and free markets on talk-radio stations all across the country as well as on Fox News' Neil Cavuto and Greta van Susteren shows and he appeared as a regular commentator on Judge Andrew Napolitano's show Freedom Watch. View these interviews at LewRockwell.com and from Full Context. Send him email.