Whitewater Photography Tutorial #4
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Keeping our expose to the right rule in mind, how about those deep, dark canyons and rain fed rivers. Sometimes they have the most epic scenery but can be hard to photograph well. I’ll tackle the second most common issue in whitewater photography, motion blurred photographs.
When there is not enough light to shoot our ideal settings, it’s time to play a game of balance with our three previously mentioned controls, Shutter Speed, Aperture and ISO.
First we can adjust our shutter speed, because the slower the shutter the more light we let in. The problem with this is that rarely do you want motion blur in a kayaking shot. I consider my slowest acceptable shutter speed to be 1/500 to 1/800 depending on the situation. You will have to judge this based on the speed of the paddler and water. If you are freezing motion at the top of a waterfall, both the paddler and water will be going slow enough that 1/500 might work (although paddle blades can blur). On the other hand, if you are trying to freeze both at the bottom, they will be moving much faster and harder to freeze, and will blur. Shutter speed is the weakest of the three methods for adjusting exposure on dark days, because you only gain one stop of light going from 1/1000 to 1/500.
ISO, the equivalent of film speed, will play a role on dark days but has some serious drawbacks. Noise, the digital equivalent to film grain (except it looks worse) is the most well known drawback. Outside of noise, using a high ISO also drops your dynamic range and the sensors ability to correctly capture color. But there are occasions where there is no other option than to pump the ISO up. This is where they amount of money you spend on a camera can make a big difference. Whatever you do, do not, I repeat, do not, under-expose a high ISO shot. If you are shooting at your camera’s base ISO you have quite a bit of flexibility to adjust the exposure while post-processing. (Which will be it’s own tutorial) At high ISO’s any noise is greatly magnified if you adjust the exposure, and this can ruin a great shot, making it even worse than too slow of a shutter speed.
Example One: Shutter: 1/1000. Aperture: F4.8. ISO: 800. Post production +2.5 exposure. Nikon D50 with Sigma 18-200 @ 40mm.
Example Two: Shutter: 1/640. Aperture: F2.8. ISO: 800 Post production +.25 exposure. Nikon D200 with Nikkor 20mm 2.8.
While the difference is pretty obvious, it’s even more obvious when the images are cropped at 100%:
Although a good bit of the sharpness is due to lens choice, these go to illustrate the dangers of underexposing a high ISO shot, and the drawbacks to high ISO.
Aperture is by and far the most powerful of the three choices. Opening your aperture from 8 to 2.8 is a full three stops. This is the same as going from ISO 200 to 1600, or 1/1000 to 1/125. There are some downsides to large apertures. Large aperture zoom lenses are expensive and heavy, because it takes a lot more glass to let all that extra light in. Another downside is that on many lenses the largest apertures are not as sharp and lose contrast. As a rule of thumb you can’t shoot low light kayaking with a cheap zooms and get great results.
Option #1 is to lower your standards and shoot high ISO speeds with cheap light zooms.
Option #2 is to buy expensive fast zooms, but since they run around $1,500 and weight as much as 2lbs they add up fast. Plus 2.8 isn’t always fast enough.
Option #3 is the route I have gone. Trade away the convenience of a zoom for the light weight and (sometimes) cheap cost of a “prime” lens. Prime lenses have generally been in production a long time and are light and simple since they don’t zoom. The $110 50mm 1.8 is a great example. One full stop faster than the $1,700 24-70mm 2.8, 1.7lbs lighter and $1,600 less! The downside of shooting primes is the hassle of changing lenses on a regular basis, and more hiking to get the shot you want. Sometimes you just can’t get where you’d like to be too. They are especially tough in a rainy environment, where you don’t want to expose the inside of your camera body while changing lenses.
1/500 F1.8 ISO 250. Nikon D200, Nikkor 50mm 1.8.
The final problem with low light kayaking shots is white balance. Ever notice how most dark weather kayaking shots look “cold”? That’s because they have too much blue in them, even the best of cameras’ Auto White Balance (AWB) is not perfect. As always we have a few option to remedy the problem.
The first is to use a preset white balance that is built in. Shooting on a cloudy day? Hold down the WB button and rotate the command dial until you get to the cloud symbol. The downside to this method is that it’s not completely accurate as not every cloudy day is the same.
White Balance set to cloudy on a Nikon D50. Shot with Nikon D700 and Phoenix 100mm Macro.
The second is to leave the camera on AWB and adjust while post-processing. This works well with high end cameras that get it right 90% of the time, but with a camera like the D50 I found myself adjusting nearly every shot, way too much work.
Third is setting manual white balance with a gray card. Judging from my love of doing things the hard way (manual exposure and prime lenses) it seems like this would be right up my alley, but it’s not for two reasons. A. It’s simply too much work to set manually for every shot. B. It’s impossible to stand in the location of the actual shot to get a true white balance, and the lighting on shore is often different.
With the D50 I use the camera presets. With the D200/700 I use the AWB and adjust in post processing. You’ll have to judge based off of your camera’s AWB abilities.
Nikon D50 set to AWB. 1/500 F1.8 ISO 100. Shot with D200 and Nikkor 50mm 1.8.
Same shot after adjusting white balance (post processing tutorial to come)
To sum it up: Adjust to your slowest acceptable shutter speed & largest aperture before raising the ISO.
Hopefully this will give you some insight to capturing the moment when it’s a bit dark.
Next: Focus, focus, focus!
Whitewater Photography Tutorial #1
Whitewater Photography Tutorial #2
Whitewater Photography Tutorial #3
Whitewater Photography Tutorial #5
Whitewater Photography Tutorial #6
Darin,
Again a great posting. I was wondering about exposing the inside of a camera while changing lenses. Once I had to send my D200 to the shop because the sensor, displays and viewfinder got all fogged. That’s one of the reasons why I got the cheaper Tamron 18-250mm. Since the time between my swims is kind of short I don’t want to risk my F2.8 glass.
Jamie,
I’ve never had that problem, but then again I am lucky enough to do most of my shooting in California.
My one very wet trip was in Newfoundland, and I was still changes lenses a lot but had no issues besides fog on the outside of the view finder.
Do check your Watershed for pinholes from time to time, it’s surprising how many they accumulate if you bushwhack with it over your shoulder.
I do have some personal rules for changing lenses. I keep a dry t-shirt in my watershed to dry my hands on, and always keep the camera facing down while in the process. In cold/wet weather I keep my camera off as much as possible, the heat it generates can lead to condensation.
Expensive equipment on the river is a personal choice just like running rapids, risk vs reward. Unfortunately there is very little monetary reward for risking the expensive equipment.
I do my own sensor cleaning for dust on a fairly regular basis, it’s easier than you might think, although quite scary the first time!
Hey Darin,
Great Tutorials! On the topic of White Balance: The “cloudy” setting on my Sony A300 does work pretty well. One thing that I will also adjust if the color range is a bit “cool”, is the Kelvin White Balance. I bump up KWB +6000 to “warm” things up. Conversely, you can “cool” the color temps down if the color range is to hot. drop KWB -5600
Any thoughts?
– Shaggy
Shaggy,
That sounds like a great method too, not one I’ve ever used but more accurate once you get a feeling for the scene.
Darin,
Thanks again for all the advice.
The dry t-shirt idea is a good one to dry hands, thanks. I do have a Watershed, but keep the camera inside a small Lowepro bag within the Ocoee.
Regarding drybag placement… I hear about “keeping the Watershed between your legs”… how do you attach it? The front pillar? I place it behind the backband, trying for it to be as central as possible…
-Jaime
Drybag placement is total personal choice. On a multi-day I simply don’t have enough room to put it in the back, so I’ve gotten in a habit of keeping it up front between my legs. I don’t anchor it, and came close to losing it once during a bad swim. I think putting it in the back of the boat is safer by far, but more of a hassle to take out every time you want to take a shot.
These tutorials are as fantastic as your shots. Thanks a ton for putting these together. I’m wondering what primes you use most/carry with you (mainly focal length) and are those on a full frame sensor or cropped? Thanks.
I just finished #8 which talks about equipment. For the last year and a half I’ve used a 20mm and 50mm, then for the last year added in a 75-150, all on a cropped sensor. I did just move to a full frame sensor last month. cheers,
Darin