Long lenses and heat distortion

[Maarten]

Many things have been said about this, Steve made a couple of videos about it and I know most circumstances that it could ruin my pictures.
But still, every now and then it takes me by surprise.
Maybe I still don’t know enough about it? Maybe the options of photographing with a long lens are limited ?
Just yesterday I got out a little later then planned, it was 9 am and it was getting hot already here in Mexico. Around noon it is around 40c (110F).
I was sitting on some rocks, surrounded by more rocks and very shallow water, there was a snowy egret feeding itself at maybe 30 or 40 feet away. The camera was resting on my feet and I used the screen to focus. I had been there for a while and the egret didn’t worry about me.
Nice circumstances except for the harsh light but this white bird against the green/brown background was too beautiful to resist.
Not a single sharp picture. Ugh.
Is this the situation that things simply don’t work? I thought the rocks and the shallow water would have the same temperature so heat distortion shouldn’t be a problem but apparently it was. Please tell me I’m not the only one running into this.

 

[Cameron T]

Welcome to atmospherics. Shooting in hot weather can get you at any time, especially when you're shooting over different surfaces.

It's not a long lens thing, you just notice it more with them. It's the nature of how temperature variations in the air bends the light and makes everything 'softer'.

You could have also had a lens hood on, or had gear that wasn't acclimated yet, or a few other things that could do it too.

 

[JAJohnson]

Many things have been said about this, Steve made a couple of videos about it and I know most circumstances that it could ruin my pictures.
But still, every now and then it takes me by surprise.
Maybe I still don’t know enough about it? Maybe the options of photographing with a long lens are limited ?
Just yesterday I got out a little later then planned, it was 9 am and it was getting hot already here in Mexico. Around noon it is around 40c (110F).
I was sitting on some rocks, surrounded by more rocks and very shallow water, there was a snowy egret feeding itself at maybe 30 or 40 feet away. The camera was resting on my feet and I used the screen to focus. I had been there for a while and the egret didn’t worry about me.
Nice circumstances except for the harsh light but this white bird against the green/brown background was too beautiful to resist.
Not a single sharp picture. Ugh.
Is this the situation that things simply don’t work? I thought the rocks and the shallow water would have the same temperature so heat distortion shouldn’t be a problem but apparently it was. Please tell me I’m not the only one running into this.

You’re not the only one having such a problem. In the situation you describe I’d assume heat distortion would be a factor in preventing sharp images.

 

[Maarten]

Welcome to atmospherics. Shooting in hot weather can get you at any time, especially when you're shooting over different surfaces.

It's not a long lens thing, you just notice it more with them. It's the nature of how temperature variations in the air bends the light and makes everything 'softer'.

You could have also had a lens hood on, or had gear that wasn't acclimated yet, or a few other things that could do it too.

I have been reading a lot about it and apparently there’s not much you can do. Frustrating sometimes, it’s okay if you can go back another time but my way of travelling (over water by boat) doesn’t allow me to do so.
I had the lens hood on but with splashing sea water al around me I’d rather leave it on. I was there for hours already so the gear must have been acclimated.
Thank you for the suggestion though.
Don’t photograph, change the travel schedule and come back later is the solution I guess.

 

[DRwyoming]

Yup, it can happen in many different situations: hot, cold, over water, over heated surfaces, shooting from a warm house or car through a window to colder air, shooting across the hot hood of a car, etc.

But as posted above, it’s not really a long lens thing but shooting across distance or through a lot of locally turbulent air. A 600mm or 800mm lens shooting small warblers near the minimum focusing distance might not experience any atmospheric image softening unless there’s a lot of local air turbulence but the same lenses shooting a larger subject at several hundred feet away will often experience atmospheric degradation in less than ideal situations.

 

[Maarten]

You’re not the only one having such a problem. In the situation you describe I’d assume heat distortion would be a factor in preventing sharp images.

I recognize that my threshold of acceptance went up over the years. I know now what this lens (Nikon’s 600mm f4 ) is capable of and when it’s not that sharp then I’m disappointed and they’re deleted.
It’s good to know that I’m not the only one.

 

[Maarten]

Yup, it can happen in many different situations: hot, cold, over water, over heated surfaces, shooting from a warm house or car through a window to colder air, shooting across the hot hood of a car, etc.

But as posted above, it’s not really a long lens thing but shooting across distance or through a lot of locally turbulent air. A 600mm or 800mm lens shooting small warblers near the minimum focusing distance might not experience any atmospheric image softening unless there’s a lot of local air turbulence but the same lenses shooting a larger subject at several hundred feet away will often experience atmospheric degradation in less than ideal situations.

Exactly, that’s why I didn’t expect this at 40’. With birds in the water I shoot as low as I can with the lens sometimes literally on the ground. Maybe that contributes to the problem?

 

[jeffnles1]

Exactly, that’s why I didn’t expect this at 40’. With birds in the water I shoot as low as I can with the lens sometimes literally on the ground. Maybe that contributes to the problem?

You're not alone here. Some days are worse than other. It's not really heat, it is the differential between warm/cold or hot/warm air masses that cause light diffraction when the two temperatures meet. I do not live in a desert area but find massive amounts of differential distortion when shooting on sunny cold days where the air is cold but the rays of the sun warm up the ground and the couple yards or so above the ground show lots of the distortions.

You mentioned you were in Mexico, shooting around rocks and water. That could create a good degree of difference between the warmer air coming off the rocks and the cooler air around the water.

Bottom line, I think we've all been there with the same frustrations. Sometimes it is best to just look back at the photos as reminders of a great time out with nature and off to capture better images on a different day.

Keep on shooting.

 

[Warren D]

I'm in southern New England and last weekend I was getting atmospherics at 8am. Sun up is around 5:30am so it only took a couple of hours of sun to get the heat waves going. As you are substantially south of me, I'd expect heat waves by 9am. Any surface will soak up those UV rays, the darker in tone the more it'll heat up.

 

[SCoombs]

Last week I photographed a big outdoor event with people in the heat of the day and was really frustrated with what I think was heat distortion I was fighting much of the day. Some of my shooting was at shorter focal lengths but a lot was with the 70-200 and on that lens I had a LOT of photos which were really just not as sharp as I would have expected with the heat over the distance being the factor I found had to reason was most likely to cause the issue. This kind of thing unfortunately can come up in all sorts of situations, in other words.

 

[peachfront]

Many things have been said about this, Steve made a couple of videos about it and I know most circumstances that it could ruin my pictures.
But still, every now and then it takes me by surprise.
Maybe I still don’t know enough about it? Maybe the options of photographing with a long lens are limited ?
Just yesterday I got out a little later then planned, it was 9 am and it was getting hot already here in Mexico. Around noon it is around 40c (110F).
I was sitting on some rocks, surrounded by more rocks and very shallow water, there was a snowy egret feeding itself at maybe 30 or 40 feet away. The camera was resting on my feet and I used the screen to focus. I had been there for a while and the egret didn’t worry about me.
Nice circumstances except for the harsh light but this white bird against the green/brown background was too beautiful to resist.
Not a single sharp picture. Ugh.
Is this the situation that things simply don’t work? I thought the rocks and the shallow water would have the same temperature so heat distortion shouldn’t be a problem but apparently it was. Please tell me I’m not the only one running into this.

You're not the only one. I ran into it a few times in Senegal one my first real photo journey. I was thinking about so many new things at once I forgot about heat distortion & got frustrated with myself a few times... Highs were 109 degrees F. & skies were utterly cloudless... I thought I couldn't focus a picture on a bet but eventually figured out what was going on and got some nice shots too... but in some conditions a really crisp shot was just not gonna happen.

 

[Maarten]

You're not alone here. Some days are worse than other. It's not really heat, it is the differential between warm/cold or hot/warm air masses that cause light diffraction when the two temperatures meet. I do not live in a desert area but find massive amounts of differential distortion when shooting on sunny cold days where the air is cold but the rays of the sun warm up the ground and the couple yards or so above the ground show lots of the distortions.

You mentioned you were in Mexico, shooting around rocks and water. That could create a good degree of difference between the warmer air coming off the rocks and the cooler air around the water.

Bottom line, I think we've all been there with the same frustrations. Sometimes it is best to just look back at the photos as reminders of a great time out with nature and off to capture better images on a different day.

Keep on shooting.

I agree, that’s the best way to look at it. Sometimes I even enjoy sitting there and watch wildlife without photographing. Thanks for the reminder.

 

[tclune]

I can imagine a Mad magazine parody of photography publications: Global Warming -- How Will It Affect Your Photography?

 

[Tibor Hrnko]

I think that it would be more correct to call it an issue of a long distance between a camera and a subject.

It occurs when when we want to increase the angular height of an distant object using longer optics. E.g. photographing a planet of Saturn through the Earth atmosphere.
All will be OK if we use the same lens to increase the angular height of a small beetle just in front of us.

 

[wotan1]

I have encountered this issue a few times lately. We had a nice outing at a nature preserve but the rules required that we stay In our vehicles. Most of the images that day were sub par.

We also made it to a great Eagle spot. Could not get there until late morning/midday and most of the images were soft.

Headed out this coming week to an area with great bird potential and will be shooting for a few days.

I am going to work on trying to shoot close to sunrise/sunset before things heat up. I will see how that works and report back.

All this says something about working with widest possible aperture lenses. That and getting up super early. Plus try to shoot subjects that are closer.

 

[PhotoLover]

I have encountered this issue a few times lately. We had a nice outing at a nature preserve but the rules required that we stay In our vehicles. Most of the images that day were sub par.

We also made it to a great Eagle spot. Could not get there until late morning/midday and most of the images were soft.

Headed out this coming week to an area with great bird potential and will be shooting for a few days.

I am going to work on trying to shoot close to sunrise/sunset before things heat up. I will see how that works and report back.

All this says something about working with widest possible aperture lenses. That and getting up super early. Plus try to shoot subjects that are closer.

I don't think using a faster lens (wider aperture) will make any difference, unless I'm missing something. The problem is the heat distortion. Sometimes, it will be impossible to get a sharp image. Not hard. Impossible, if the subject is far enough away near the surface. It is vexing.

I take less pictures in summer than in winter in my area ..... definite heat distortion issues. And so many hours of the day have terrible light anyway.

 

[BillW]

When heat distortion looks like it might be a problem, I often try shooting bursts, even of static subjects. It seems to me that atmospheric distortion is not constant and when I shoot a burst I sometimes get a few images that are sharper than the others.

 

[Cameron T]

That's generally correct. Lucky imaging for astro relies on that fact.

Of course, sometimes the rate of pictures being sharp is still 0 and there's nothing you can do about it.

 

[wotan1]

That's generally correct. Lucky imaging for astro relies on that fact.

Of course, sometimes the rate of pictures being sharp is still 0 and there's nothing you can do about it.

Been there done that.

Not to mention all the time spent sorting through all those rapid fire bursts trying to find anything good enough.

Sometimes you have to just come back another day and another time. You can always go back through your catalog of keepers. That helps you realize there is always more to come.

What a crazy sport.

 

[Calson]

Wildlife will also be far more active at sunrise which is also important. Birds begin their morning chorus at 4:30 am at this time of the year.