Thursday, August 26, 2010

Photography Case Study: “Hell’s Freezing Over”

Here we are again with a before and after case study. This article will also consider environmental variables, as this photo was taken in -6° air with a wind chill of -22°.

"Hell's Freezing Over" Post-processed for web.
"Hell's Freezing Over" As it was birthed from the D90.

Image details.
Nikon D90, Nikkor 70-300 VR at ISO 200, 70 mm, f7.1, 1/800 sec. JPEG with automatic white balance set to Shade, Neutral image setting, VR off, no flash. Program exposure mode (P on most camera dials, where most settings are automatic but adjustable, as opposed to what I call “Full Idiot Auto,” the green Auto on many camera dials) with Nikon’s 3D color matrix metering engaged.

Environmental considerations.
Nikon specifies the operating temperature range for the D90 as between 32°-104°. As I mentioned above, it was nearly 40° colder than that when this photo was taken.

Electronics do not work as well in the cold as they do otherwise. Even the flagship Nikon D3s specifies 32°-104°.  The top of the line Canon 1D Mk IV specifies 32°-113°. Obviously, there are a lot of photos we want to take beyond these temperature ranges. Planning ahead is essential.

LCD displays will begin to move slowly and gel together before failing altogether if you remain in the cold long enough. Don’t plan on using live view (for long, anyway) if your camera is so equipped. The battery will not last nearly as long. Cheaper (i.e. not Nikkor) lenses may begin to have difficulty focusing as their internal lubrication begins to gel. Nikkors seem to avoid this problem because they’re well-built and don’t rely on an overabundance of internal lubricant.

Knowing what you’re up against, you can work to mitigate these issues.

Carry at least one spare, fully charged battery with you. Keep it in a pocket near your body to keep it warm – you’ll get better use out of it that way. Avoid live view. With the LCD screen performance so reduced, it may become useless and it will certainly chew up your batteries faster. I recommend disabling VR (image stabilization) in Canon and Nikon bodies, because they rely on moving elements in the lens, which will reduce available battery and may fail to help at all because of the aforementioned lubrication issues.

When you return from your shoot, warm the camera and lens up slowly, in a humidity controlled environment if possible. The cold camera components hitting warm air will cause condensation, which will corrode those millions of transistors and circuits in a digital camera. If you note condensation, remove the battery and keep the camera off until it has a chance to dry completely.

Of course, you needn’t only prepare your photography equipment for extreme weather but you must also be ready. I see no reason to rehash what is written so well elsewhere about how to dress for the cold. Do it! I also keep a pair of leather gloves in my shooting bag, with the fingers cut out where it aids in controlling the camera.

Unless I’m shooting long glass (a 70-200 f2.8 or heavier) I rarely use a monopod. However, you may want one in cold weather, or a tripod if possible, to reduce shiver-shake. A tripod was out of the question in this case because I knew I would be moving around.

Fig. 1
Technique.
This composition relies heavily on the triangle of ground and its color to provide depth. I’ve desaturated the image in Figure 1 to illustrate the loss of depth in black and white. This is assisted with color for two reasons: the color-contrast itself, and the colors here specifically: the brain processes blue as further away, i.e., sky.

Lens characteristics.
As mentioned above, this image was captured on a D90. (In fact it was shot 3,087 on the camera so I was barely getting acclimated to it at this point.) The D90 does remove LCA (see “Bathroom Door” for a discussion on LCA) in JPEG, although the 70-300 is a good performer on the DX D90 as it is a full-frame lens.

As an ED (extended low dispersion) glass lens, the 70-300 also does a good job of controlling lens flare. I did not shoot with the included hood and had a protective UV filter on the front of the lens. I used my left hand, also supporting the lens, as a hood. The sun was beginning to burn through the fog at about 8 o’clock in this photo and about 30° elevation.

At 70mm on DX distortion is well controlled. Along the critical horizon line I am unable to fix the slight “suck” distortion in Photoshop CS4 because the lens correction tool does not allow adjustments smaller than 1. Nevertheless, with the assistance of the fog it is nearly impossible to see the distortion anyway.
There is good depth of field at f7.1 and 70mm. The near sharpness in the rocks and brush on the coast help provide contrast with the foggy water. In hindsight I would have shifted program (most good cameras allow you to override the selected aperture and shutter speed in Program mode by spinning a dial) to f11 for even more depth of field, perhaps f13. In my experience, f11 is the useful limit for careful reproduction with the D90/70-300 team; beyond that diffraction limits performance.

Camera configuration.
Breaking news is different from making careful compositions in a studio. Both have their challenges. In the studio you can be overcome with variables to control, called paralysis by analysis. In the field you might have a few minutes (as I did in this case) to prepare for the shot, or you might have to draw your camera from its bag shooting, otherwise missing the shot.

When you’re heading to an unfolding situation you want to be ready to go as soon as your car door opens. In this case, I knew Search and Rescue would be attempting extrication this particular morning, after they had given up on the two men the night before. (The story is reproduced below if you care to read it.)

I always carry a spare, fully charged battery and this time was no different, except I shoved it into my long underwear pocket to keep it as warm as possible. The camera was set to base ISO, 200 in the case of the D90, with my longest glass (the 70-300) attached. I kept the camera as warm as possible, as long as possible, leaving the open camera bag under the heater in the car until I arrived.

Not knowing how much time I would have, the camera was set on defaults. ISO 200 would be fine given the light available at 10 a.m. For press (as in newspaper printing) I shoot in Neutral scene mode, otherwise there is too much saturation. As I’ve done here, saturation can be dialed up later, but too much too early often leads to over-exposure. (Nikon’s 3D Color Matrix Meter is generally good about taking these things into account, but not so with overzealous in-camera saturation settings, for some reason.)

Advance was set to continuous high and autofocus was locked on center sensor with AF-hold so I knew where I was targeting. Focus on the boat, lock, recompose while manually shifting focus toward the shore just a hair to compensate for the boat’s movement while I was recomposing. (Most Nikkor AF-S lenses allow manual focus override without moving any switches – just grab the focus ring. The cheapest – 18-55 (all three variants), 55-200 (both variants) and by the looks of it the newest 55-300 VR are branded AF-S but do not allow instant manual override. Keep that in mind if you’re a photojournalist.)

Finally, I used a monopod because I knew it was going to be damned cold. I was fortunate my car started.

Shot technique.
This is where the preparation pays off. After the rescue boat launches I muddle around looking for the best place for the shot. On this shoreline I find the best lighting – from over my left shoulder. It’s damned cold, and I’m cold, but I’m OK because I knew to prepare. (I also knew the two men SAR was after had spent the night on the lake, so it could have been much worse for me.)

Because I was shivering and because I needed to disable VR I knew I would need a high shutter speed. Program selected 1/800 sec. at f7.1, which was adequate. Again, if I had it to do over again I would have boosted ISO so I could select a smaller aperture for greater depth of field while maintaining the high shutter speed to minimize blur.

After finding a perch it was simply a matter of waiting for the boat. Here is a conundrum. I knew after my 20-30 minute wait the battery would be wearing thin. Do I run with it and hope I don’t miss the shot? Or do I risk missing the shot by switching to my warm battery?

In the end, I was fortunate. The rescue boat was unable to raise the shore, so a radio relay man was dispatched to the top of the hill visible in the foreground of this photo. When I heard him relay that the boat was incoming, I quickly swapped to a warm battery.

Taking a picture is an awful lot like shooting a gun. Focus on what you’re doing. Take a deep breath and expel it slowly, controlled. This is particularly important when it is below zero and you’re shivering. You probably won’t be able to stay as still as if it were 70°, and you certainly won’t be able to do it for long. But if you channel your focus, you might be able to have enough of a Zen moment to get a few worthwhile photos.

Post processing.
Let’s discuss post processing for print and web. They’re two different animals.

Most of my shots have a peculiar look to them, my style, my business card. For print, especially newsprint, many of these effects are not possible. This plays into post processing.

Newspapers are printed in four-color, CMYK. In this context, black is a color (but called K in CMYK for some reason). Computer monitors are RGB with rear illumination. Any given image is going to look different if you just change from RGB to CMYK in Photoshop and export. (Cameras capture in RGB.)

It is difficult to get the same punch from images once printed on newsprint. Newsprint isn’t exactly white, which colors whatever you put on top of it. It’s usually pretty low resolution, too: maybe 85 lpi (lines per inch) which is roughly compatible with 170-220 dpi (dots per inch, how resolution is usually considered in Photoshop and consumer printers). Fine details are going to be lost. When working with older presses, other problems can crop up, but we won’t get into those here.

For our purposes, have a look at the screengrab of the newspaper PDF below. Compare how the photo looks there and in the web-prepared image.

It looks like someone sucked all the cyan out of it, doesn’t it? The water looks flat and boring. This is because our press had a tendency to pour on the cyan, so our photography director had to turn down the cyan before sending it out. The finished product has similar color to the web-prepped image.

The bottom line is to know your medium. When printing images professionally, I often prefer Kodak Professional Metallic paper. If you’ve not seen a landscape printed on KPM, you’re missing out. It positively sparkles. Other projects may call for other paper, and they all behave differently.

The key is practice, practice, trial and error, more practice, more error, and finally finding something that works. Most helpfully, Adorama, where I do most of my printing, offers ICC profiles for their different papers. Use the profile! (See here for pricing, profiles are at the bottom of the screen.)

I won’t talk too much about the particulars of prepping for newsprint. The newspaper I was at when this photo was taken is a particular case; most folks have moved onto image setters which work better than shooting negs of separations. (If you don’t know what any of that means, feel fortunate.)

One thing I will note: we sent it to press without straightening the damn photo! Whoops! Deadline pressure.
Surprisingly enough, this photo didn’t require much work in post for the web. A pinch more exposure (+.1 EV), substantial recovery and a few blacks were added in. I switched to a stronger contrast curve and punched up the saturation about 30%. And of course, I straightened the horizon.

The idea behind the various adjustments was to present a photo as close to what I saw out there as possible. Unlike other compositions (such as the one I discussed Tuesday), in photojournalism you often want to constrain yourself from going too far from what happened. (See, for example, the occasional messes about someone’s teeth being overwhitened or skin blemishes being removed or just plain lying about where a photo came from.)

In almost three years of using Lightroom and shooting Nikon dSLRs, I have yet to find a situation in which Lightroom’s “automatic” white balance gives a better result than what the camera spat out in JPEG (or NEF, for that matter). Lightroom almost always seems to skew too warm for my taste. White balance is unmolested here, after having shot auto.

Conclusions.
In breaking news, the mantra is, “Don’t let the perfect become the enemy of the good.” Too often we’re spinning dials, swapping lenses or checking the last shot when we should be nailing the one right in front of us.

I was fortunate in this situation and maximized that good fortune with planning. The sun, and hence the lighting, worked to my advantage. I had an idea of where the boat would be returning from. At some point, you do what you can do and then sit back and cross your fingers.

It also helps to take a lot of photos. Not necessarily via the “spray and pray” method, but because you never know what’s going to work and so you want a lot to work with. The best photo from this soiree was going to get whatever play it needed as the lede that week, but often the editor will want a horizontal photo instead of the vertical one you prefer.

And with that, I think I’ve written about all I can about this photo. As always, comments are welcome.



Image grade.
Original: B +
Post: C

Two guys came in from the cold. I managed to get the shot, and it didn’t need much help in post.

I welcome and invite suggestions for this column and critiques of this composition. Please leave a comment on the blog or email me at jonathan.e.green@gmail.com. I suggest you put “Photography Case Study – Bathroom Door” in the subject line so I find it if Google’s excellent SPAM filter eats it.

Next Tuesday we consider some critter photography, or which I have scads.

"They Come in Threes'"

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