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Archive 2011 · how can I beat heat shimmer ?

  
 
gdanmitchell
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p.2 #1 · p.2 #1 · how can I beat heat shimmer ?


+1

The condition most certainly occurs in conditions that are not hot. I ran into it earlier this year when making long lens photographs of the Golden Gate Bridge very early on a cold and hazy morning.

The suggestion to use a higher camera position could well help in some instances, especially if the "heat wave" effect is coming right off of the ground. However, here too, the effect is more prevalent than many realize. Going back to the Golden Gate Bridge photograph, I was many hundreds of feet up above the bridge in the Marin Headlands, and the bridge itself is far above the water line... yet I had quite a bit of fine distortion caused by this effect. More recently I was making some photographs of the Pacific from high on coastal bluffs and was surprised to find some very distinct signs of the effect.

I'm convinced that among the reasons people will report that some long lens "isn't sharp" is that they haven't yet come to understand all of the tricky aspects of using such lenses.

Dan


kwalsh wrote:
As mentioned already "heat" shimmer isn't really a good description as you get the effect on both hot and cold says. All you need is a difference between the ground temperature and air temperature for things to go wavy on you. Happens on sunny winter days all the time.

The only two things I've found to help the situation are:

- Get higher, the less of the air column close to the ground you shoot through the better. If you can find a higher vantage point to shoot from do that.

- Shoot when the air and ground temperatures match. There are a
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Dec 30, 2011 at 12:52 PM
threemilesfina
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p.2 #2 · p.2 #2 · how can I beat heat shimmer ?


TrojanHorse wrote:
Move to Canada?


lol nice try. I even deal with heat distortion and I can fly to Greenland in the same amount of time it takes to get to Ottawa.



Jan 03, 2012 at 09:14 AM
skibum5
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p.2 #3 · p.2 #3 · how can I beat heat shimmer ?


I do have to say that the effect pops up a lot more often than people think and in a MUCH wider variety of situations than people believe it can.

I've even had AF go batty even on a natural turf field when shooting sports when nothing was visibly odd to the naked eye. (I was using 20D/40D/50D and someone else 1D2n and someelse a rebel, all of us had weird stuff going on, one person using a short 70-200 on rebel for a while had better focus than any of the rest of us I guess the shorter focal length meant she was focusing more on shooting players closer in; the nikon guy insisted he had no issues whatsoever though, not sure what to make of that, that guy was an experienced and skilled shooter so I'd think have noticed if something was amiss, weird, I think his main goal was small web images from that shoot so maybe he only looked at itty bitty versions?)

gdanmitchell wrote:
+1

The condition most certainly occurs in conditions that are not hot. I ran into it earlier this year when making long lens photographs of the Golden Gate Bridge very early on a cold and hazy morning.

The suggestion to use a higher camera position could well help in some instances, especially if the "heat wave" effect is coming right off of the ground. However, here too, the effect is more prevalent than many realize. Going back to the Golden Gate Bridge photograph, I was many hundreds of feet up above the bridge in the Marin Headlands, and the bridge itself
...Show more


Edited on Jan 03, 2012 at 06:45 PM · View previous versions



Jan 03, 2012 at 02:42 PM
rscheffler
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p.2 #4 · p.2 #4 · how can I beat heat shimmer ?


Deborah Kolt wrote:
Interestingly, I gave the new 400 f2.8 II a workout on a brilliant sunny day on field turf where the heat waves were visible - everyone's nightmare. Shot from five yards behind the goal posts, sitting directly on the turf. My original 400 and 600 would have given me frame after frame of oof shots; in these conditions, I usually go with a 300 and chase the action along the sidelines until later in the afternoon when the sun is at a lower angle. The new lens had some heat haze issues at 100-80 yards away, but only intermitently
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This is interesting. My experience with the 1DIII and the original IS series 400 & 600 on Field Turf is identical to yours. I'm not sure , even after a couple years, that I can say the IV is much better, though it does seem to be a more resistant to massive AF misfocus fluctuations in these conditions. Purely speculation but there could be something to the revised AF drive algorithm of the version II lenses, such as faster communication to better allow the camera to find the most optimum sharpness. Shooting across heat waves on Field Turf I've often found that I can manually focus on a stationary subject with better sharpness than the AF usually provides, but once the subject starts moving, I just don't have the skills anymore to manually get consistent focus.


gdanmitchell wrote:
I'm convinced that among the reasons people will report that some long lens "isn't sharp" is that they haven't yet come to understand all of the tricky aspects of using such lenses.

Dan



I agree. Even though RG denied it was a factor in his infamous 1DIII and 1DIV follow up AF tests, I strongly suspect that it had an influence on the ability of the AF system to find a consistent lock in hot conditions. If you consider how outright jumpy and sensitive the 1DIII was at first release, it's conceivable that any slight shift in apparent focus could cause the AF system to try to compensate, and in the meantime the focus has shifted again. Throw in a moving subject...



Jan 03, 2012 at 05:42 PM
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