Tuesday, August 31, 2010

Photography Case Study: "They Come in Threes"

Well, we've come to it. A composition I like, but with terrible technical image quality. Totally smoked, really. Useless at any size larger than a 4x6" print. Perhaps some day serendipity will strike again — while I'm visiting Thermopolis, no less — and I'll have a second chance.


There are no second chances.


So I'm stuck with this, which should be a winner, but a number of mistakes cost me the image.




You can, as they say, tie a bow on crap, but it's still crap. I haven't spent much time in post because there just isn't any saving this image. But it was instructive for me to have a look at it to see where I went wrong. This was one of the first images I took on a dSLR and I didn't really have a clue about the differences between digital capture and, say, a Nikon FE.


Alright, let's get to the tech specs so I can start tearing into this.


Nikon D80, Nikkor 17-35mm, 22mm, f22, 1/800 sec., ISO1600, program auto with matrix meter and no exposure compensation. No flash.


Two numbers above stand out and ruin the image. Each digital camera has it's own "DO NOT EXCEED" ISO sensitivity. To add to the problems, that setting is rarely the highest numbered setting, and that setting may change with conditions. On the D80, with such a challenging high-contrast shot, ISO 400 would probably have been the highest safe setting (if that). Whoops.


The second problem is that tiny f stop. The larger the number, the smaller the diaphragm. Larger diaphragms (smaller f numbers) collect more light but at the cost of depth of field, and at extremely large settings, other problems crop up, too. Smaller diaphragms (larger f number) collect less light for greater depth of field at the cost of longer exposures or higher ISO settings. And extremely small aperture settings cause diffraction. (See Rockwell for a technical discussion on diffraction. For those uninclined, squint. Notice how things begin to go fuzzy?)


Again, there are no hard and fast rules. Different lenses on different camera bodies suffer from diffraction at different times. When shooting critical work, things can get even more complicated because many lenses don't hit their prime until you begin to stop-down a bit. If you know you've got an important shot but don't know enough about your setup to make a decision, remember two things:


· f8 and be there. f8 is almost always a safe choice, stopped-down enough to avoid blurry corners but not so small as to cause diffraction.
· Use the lowest ISO possible. Whichever ISO setting you use will be determined by circumstances, but set it as low as possible.


So what did I lose by shooting at ISO 1600 and f22? Let's have a look:




Shoot me now! It looks like I smeared Vaseline on the front of my lens. Everything has gone blocky and splotchy, with noise everywhere. Look at the poor cow's horn: sharpening artifacts at the edge and nasty color banding throughout. There's zero texture left in her fur, either. This is after some post processing. You can note similar problems in the full image; look especially at the sky, where JPEG banding and splotching are immediately apparent.


This brings us to a point: post processing is important, even vital. But you can't save pixels in Photoshop that were never there to begin with. You only have the data you collected when you pulled the trigger to work with.


This was always going to be a challenging image to capture because of the high dynamic range. That's the distance between the darkest and lightest areas in a photo. Dark brown bison with blistering white snow are hard to capture even when you're not doing stupid things with your aperture and ISO. Unfortunately, fill flash (to lighten the bisons' fur) was impossible here because of the distance they were from me — flash efficiency drops exponentially as distance increases — and because of the truck mirror.


So, even if I had set ISO and f stop correctly, could I have gotten this image? Maybe if I had bracketed, that is, taken two exposures one after the other at different shutter speeds. (You can bracket for about anything: ISO, f stop, white balance, saturation, &c.) Bracketing for HDR (high dynamic range) merge without a tripod and still subject matter is difficult, though, and would have required a lot of time in post. If you move the camera, change zoom or your subject moves, that's it.


As a general rule of thumb, newer cameras can handle difficult situations like this better than older cameras (like the D80, which had other shortcomings as well). Auto D-Lighting is a setting in newer bodies that tries to combat these difficult situations. Would it have worked here? If I had all my other settings correct, that is, shooting at about ISO 400, f8, 1/60 sec., perhaps. I may need to open up one stop for those figures to work, to f5.6, which presents depth-of-field issues. But in such harsh light ISO 800 is probably out of the question, and I don't know if I could have held the camera steady enough at 1/25 sec.


Let's talk composition.


Fortunately, there isn't much to discuss. I can see three things I would have changed and one of them was beyond my control.


· Windex the mirror, idiot.
· Park further back than I did, which would have put the two foreground bison higher in the image with less wasted sky and enlarged the bison in the mirror. I would have also needed to have moved the jack in the back of the truck (the red handle sticking up), which I should have done anyway.
· Ask bison #1 to turn anti-clockwise just a hair so her aspect is about the same as the other two.


As I mentioned, there really isn't anything I could have done about point #3 above. Maybe — maybe — I could have approached from a slightly different angle and split the difference between the two foreground bison. But probably not.


So, had I ironed these issues out, what makes this image compelling, even if it's garbage? There are three elements, the bison, that are more or less the same. They're facing the same direction, mostly at the same aspect. They get smaller. Unfortunately, the top 1/4 of the image is wasted space, and there's too much image clutter in the mirror, with all my junk in the truck and the distracting urban-camouflage paint.


Here's the out-of-camera original:






Conclusions.


f 8 and be there.
Keep your ISO down.


It's a hard world out there, to grab what initially looks like a great image, just to see it fall to pieces when you get back to the computer and look at it with a critical eye. I've got a hard drive full of these suckers, and I'm sure we'll return to them at points in the future.


Image grade.


Original: F
Post: D



While I still love the concept, the execution kills this photograph. It's worthless, except as fodder for photography discussions on the blogs. With lots of post processing, I might be able to salvage enough of this image to make it useful as a small photo for the web. Additional post processing includes much more work on the sky (sensor spots, JPEG banding and splotching), Photoshop removal of the jack handle from the bed of the truck and trying to clone in some texture on the bison. If I really wanted to get fancy, I might use some pixel stretching techniques to rotate the mirror anti-clockwise and try to get bison #3 standing level, too. That would have been much, much easier if I had just adjusted the mirror before shooting.


Next time...


Friday we'll have a peek into this photo:


"Fireside Chat"
Things are looking better already!

Monday, August 30, 2010

Nikkor glass: Good-buys and Good-byes

I gave my advice on purchasing used or refurbished Nikon dSLR bodies here, now I'll talk about lenses.

I'm not going to give pricing level indicators as I did with the bodies. Once you find what you're looking for, price check with others to make sure you're not being taken.

I have experience with all of these.

First off, let's start with the

Good-byes: Nikkor lenses I would avoid
18-105 VR. The D90 kit lens, I was never particularly happy with it. The VR didn't seem to work well, AF-S manual focus override (being able to turn the focus ring instantly to override autofocus) didn't seem to work at all, and it seemed soft. Maybe I just got a bad sample, which I'd like to hope, because this lens could otherwise be a more affordable alternative to the 18-200.

18-135. My objections are similar to the 18-105VR. Low image quality, crummy build.

18-55/18-55VR/18-55VRII. Unlike the above two lenses, I'd be perfectly happy to find one of these gems in my bag. But I wouldn't go out and purchase one. Lack of autofocus override sinks the deal for me.

55-200/55-200VR/55-200VRII. Same as with the 18-55s, I wouldn't hesitate to shoot with one of these lenses, but if it's my dosh, I'd spend it elsewhere.

14-24. If you need it — and if you can afford it — you're probably not reading this blog for advice. For us mere mortals, I would recommend the 16-35 f4 instead.

Good news: that's it! Not too many Nikkors I've used make the DNP list.


Good-buys: Nikkors I'd put in my bag
18-70
. A forgotten lens from the D70 days, but excellent. No VR, otherwise a fine piece of kit.

16-85. A little wider and a little longer than the 18-70, but also considerably more expensive.

10-24DX or 12-24DX. Get the 10-24 if you need the extra 2° at the wide end, the 12-24 if you need better build quality. The 10 is an f3.5-4.5 variable aperture lens, while the 12 is fixed at f4.

17-35. In a pinch this lens doubles as a weapon, a plus for photojournalists shooting in dangerous parts. The new 16-35 performs much better wide open and in the corners and is reputed to be built just as well, but for serious PJ work I'd prefer the 17er. Fixed f2.8 is a plus, too.

70-300 VR. Make sure you get the VR model, not the ED and not the G. (They all pile up. The bottom of the pile is the 70-300 G, followed by the 70-300 ED G and then the top of the heap, this 70-300 AF-S VR G.) If you're shooting with almost any daylight, this is enough.

18-200. If buying used — and I wouldn't hesitate to — I'd look especially for the first generation without the zoom lock. That one little thing seems to add quite the price premium, when the glass inside is the same. So long as you know what you can reasonably expect from this lens, you should be happy.

35 1.8 DX. Every DX shooter should have one of these. Period. FX shooters would do well to consider...

50 1.8 AF-D. An excellent, excellent time-tested design. If you have the money, need the extra half-stop or need instant manual focus override (AF-S), go ahead and drop another $300 or so on the...

50 1.4 AF-S. Zoom-zoom fast in low light, but no zoom. Get it?

85 1.4 AF-D. Nikon just released an AF-S update to this venerable glass but I doubt there's enough difference to justify the price difference.

I've not shot with it, but... 24 1.4. I hear good things about it from the early adopters. Of course, you will pay for the privilege of seeing in the dark: about $2,200. In case you want to get smart, the discontinued 28 1.4, which shouldn't perform as well as the new lens, goes for over $3,000 used. Ouch.

Used and Refurbished Nikon dSLRs: Good-buys and Good-byes

I would have no reservations about purchasing a used Nikon dSLR from a reputable dealer or trusted friend. Here are a few I have experience with and would be especially interested in, with price points:

Used good-buys:

Nikon D70/D70s. Up to about $150 body only, $225 with the excellent 18-70. Probably the largest leap forward Nikon made in a single bound. Even though the original D70 is now six years old, if you can find one in good shape (again, from a reputable dealer — I'd exercise caution on eBay) I'd think about it. This was arguably Nikon's best attempt at nailing professional features and image quality uber alles in a prosumer package. I would make sure to ask about battery quality; the seller can check from the wrench menu.

Nikon D40.
 Up to about $200 body only, $230 with 18-55 I kit lens, $275 with both the 18-55 and 55-200. A few dollars more if the 55-200 is VR. The D40 is basically the D70, but with an SD slot (as opposed to CF in the '70), a bigger, nicer rear LCD and a few fewer buttons. I'd be willing to bet this has been Nikon's most prolific camera produced if sales numbers are your yardstick. Sadly, it looks like the last of the factory refurbished units are now sold.

Nikon D90.
 Refurbished by Nikon for about $750, used up to maybe $600. I shot with the D90 for over a year and loved it. A capable camera. If possible, I would advise avoiding the 18-105VR kit lens. The D90 has Nikon's second generation image processing hardware, which is good. But if a fairy dropped a D70s in my lap, I wouldn't complain and wish for the '90. (Well, maybe a little bit.)

Nikon D300.
 I wouldn't pay what many are asking. If you can find a screaming deal on one, make sure you're not being taken. But if you can find a legitimate screaming deal, maybe. I wouldn't pay more than what I would for the D90, which I think is 90% of the camera for 90% of people. The only reason to get the D300 (or D300s) over the D90 is if you shoot a lot of manual focus lenses, with which the '90 can't couple for metering.

Nikon D700.
 Used about $1,750. Can still be had new for about $2,700. Get one with a warranty or buy new. If money were nothing, this is probably the camera I would have, even against the D3/D3s/D3x.

Used good-byes:

I would avoid these cameras.


Nikon D40x/D60.
 Both about the same camera, a stripped-down version of the...

Nikon D80.
 After the D70s, it would've been nice to see its successor D80 raise the bar so high again. Unfortunately, crippled with a poor meter and sometimes-twitchy AF, the D80 failed to be much of an advancement of the D70. Either go higher (D90) or lower (D70s or D40).

Nikon D3000.
 More megapixels, more problems. I would avoid at any price, except free. (Attention D3000 owners: feel free to test my integrity and make me an offer I can't refuse. Like S&H.)

Nikon D5000.
 Similar in many ways to the D90, I would recommend this except for its flippy LCD. It's too soon, I think, to be comfortable with reliability in a used camera with a flippy screen. However, unlike the 40x/60/80/3000, none of which I would recommend at any price point, I might jump for a D5000 if the price were sweet. Maybe $350 for the body.

Nikon D300.
 They're asking too much. Don't get me wrong: the D300 is a wonderful camera, it's just overpriced. When the D90 came along it replicated 90% — maybe 95% — of the usefulness and image quality of the D300 for half the price. The only reason to pay the price premium for a '300 is if you do an awful lot of shooting with manual focus glass, because this is the cheapest Nikon that will meter with MF. That said, my brother has been making fantastic shots with manual focus glass on a D40 for years, while guessing at exposure. Having an intuitive feel for exposure is a good skill to develop anyway.

Nikon D3/D3s/D3x.
 If you can find one at a steep discount with a warranty, maybe. But these are the professional grade bodies that have seen hard use their entire lives. They're built to take the abuse, but ask yourself: would you buy a used steak supper? There's a reason it's for sale. Exercise caution.

Nikon D200.
 I'd get a D70 for a lot less, or a D90 for about the same, instead.

Bonus Photo of the Day: "Bison in Snow"

Tomorrow's Photography Case Study will pick apart a bison photo that doesn't work. I liked the concept but my execution was lackluster, to say the least.


Until tomorrow, though, he's a bonus Photo of the Day that involves bison, snow, composition and post processing — that does work. I suspect I'll dissect this image in a future Photography Case Study, so I'll spare you the tech details at this point:




See you tomorrow!


(Edit: And of course, the original from the camera:)



Photo of the Day: "Don't Feed the Wildlife"

In keeping with recent themes, here's another reminder to get closer when shooting wildlife.




Nikon D40 (6.1MP), Nikkor 18-55 I, 46mm, 1/250 sec., f11, ISO 400. Program auto, center weighted metering with -2/3EV exposure compensation. The D40 (and D80) suffer from a less reliable meter than most other Nikons, so some work with the dials is necessary to avoid blown exposures. Slow-sync flash, -2 1/3EV (this is close!). In-camera sharpening set to max (just called "+" in the older Nikon bodies), but it doesn't seem to suffer for it. Short of the D70/D70s, the D40 is my favorite older Nikon consumer body.


Post consisted of cropping to square, +1/4EV exposure, +15 contrast, increased clarity, saturation and punch. (Edit: Lightroom calls "punch" "vibrance.") I also burned (darkened) the top right corner to reduce its distractive capability and did some significant color correction. After boosting saturation and punch vibrance, my hand was beet-red. Pulling the red channel back left my watch wrist-band too blue, so I trimmed that channel, too. No sharpening, save for what Lightroom does automatically when you check "Sharpen for Screen" in the export box.


This image really is taken at point-blank range. My arm is extended to make close focus distance (call it 28" from camera sensor); that's why the f11. Otherwise there'd be no depth of field. Note that a four-year-old camera and lens combination, at the very bottom of the Nikon lineup, is capable of taking some pretty stellar photos, in terms of technical image quality.


Here's the out-of-camera original with no post except for resize and ©.







Sunday, August 29, 2010

Sunday Photo of the Day: "A Desperate Battle in a Lonely Place"

We discussed cold weather photography extensively in Thursday's Photography Case Study. Here's another from the chilly files.




Nikon D90, Nikon Series E 50mm f1.8 (an old manual focus gem), f1.8, 1/200 sec., ISO 1600. Shot natively in B&W. No metering is possible with manual focus lenses on Nikon digitals D90 and below, so I had to guess at my exposure. I couldn't use the rear LCD for two reasons: it had given up in the cold, and I had encased the camera in a grocery bag to keep the moisture out. No flash.


Like a previous Photo of the Day, this picture evokes a very lonely place, although in a different way.


Our minds expect to see something, anything beyond a football field. Stands and bleachers. A scoreboard. Coaches and staff on the sidelines. Instead, the only way we know this is a field — and that the competitors aren't just scrimmaging in a cornfield somewhere — is the goalpost. What emotions are provoked in you?


Note that, in accordance with Wyoming law, it is snowing sideways.

Saturday, August 28, 2010

Briefly: 1991 Ford LTD — "The Pursuer"

In hindsight, it may not have been the best idea to chase them, as they had rifles (air rifles, sure, but rifles all the same). We didn't know they had air rifles and we ended up breaking up a vast conspiracy.


Or something.


Mine was red.
One evening at college, I was enjoying something off the grill in front of our dorm with my compatriots. The sun was down and I remember it being a novel night.


About half a block away was the college's practice football field, elevated about 12-15 feet above where we were sitting at some point, one of us noticed what appeared to be a pickup truck pull onto the field, killing its headlights.


All men in attendance, with a teenage acquaintance to bad judgment, recognized the sounds issuing forth from the field. There was a pickup truck doing donuts up there. We were not pleased.


It was a summer evening, mind you, so most of the college was deserted. A small campus, Morningside College employed a golf cart for security purposes. The student head of security was with our merry band of suppermakers, and he called the local constabulary while another student and I decided to confront whoever was in the truck.


I will not speculate on the number of traffic strictures I broke. Between an excessive rate of speed in a residential neighborhood, a few opposite-lock-oversteer-corrected corners and a neglect for the use of headlights... there were a few infractions I'm sure.


The black Chevy pickup, probably a late 70's or early 80's model, was pulling out off the field just as the 302 in my '91 LTD was winding first gear up to the top. Fortunately, the brakes worked sufficiently well to reduce our speed before we t-boned the Bowtie.


Hmm, rifles.


Two teenagers in the cab and one in the box, with what sure looked like a rifle. Now we must give chase!


It wasn't a particularly long chase. My navigator complained when we crested a hill at such speed he ate the headliner. He had the kids' tag number. Couldn't we go home for a beer?


* * *


A few months later my friend the navigator called from his suite on the ground floor and asked me to step downstairs. I assumed he was inviting me down for a cigarette, so I grabbed my bathrobe and made for the vestibule.


When I arrived on level one, I was approached by an attractive, but suitably dressed woman of middle age, while I was doing my best Adam Dent. (I've had lots of practice wondering around in my robe — or less — in bewilderment.) The woman introduced herself as an assistant district attorney. I was confident this was not part of my plan.


Fortuitously, she was only here to serve me a subpoena, not a true-bill. My friend brought me a cup of coffee while I smoked and discussed the instrument and the latest bathroom fashion trends with her.


I went to court to testify against the three ruffians who had done a number on our practice field, but they wisely decided to cop to the charges rather than face a trial. Too bad; I had spent the entire morning in front of the mirror practicing for the grilling I would get on cross examination, and working up my self control to not stare at the ADA the whole time. Hell, I had even changed out of my bathrobe.


The youths had not only torn up the ballfield, but they had been using those air rifles to shoot out car windows throughout the neighborhood. I had visions of returning to campus a hero for helping to bring down their nefarious scheme.


***


I'll relay two other brief anecdotes about the LTD, a fabulous, honest car. It was probably the spiritual successor to the Slow Go I discussed Friday: basic, comfortable transportation.


Another friend once, rather clumsily, dropped a 4x8 sheet of snotboard on his foot, breaking it (his foot, not the snotboard). He needed to get to hospital. I so terrified him in my emergent driving he later said he would rather have walked the five miles, on that busted foot.


Another friend (#3 for those keeping score at home) and I visited Canada the winter or 2002-03. Arriving on the Canadian side of the border, I was surprised to be informed my car was suspected of running drugs. (Don't they run drugs from Canada to the US and $$$ from the US to Canada?) After four hours of dismantling the LTD, I was left with a pile of door trim, trunk carpet and a removed headliner. Fortunately, I knew the tires were properly inflated, because the RCMP (or whoever does their border duty) had dismounted them, too, in their search for powder.


No drugs found, the Canadians found the plot. They wanted us to be drug money mules! After not-so-much reassembling my car as collecting its aggregate parts, we were told we could not enter Canada unless we had $200 cash. As #3 and I were just crossing the line to say we had, and so I could have a (legal) beer at the tender age of 20, and hence only had about $20 cash. The kind Canadians told us we could return stateside, and use the ATM at the duty free shop.


With parts of the trunk in the car and parts of the car in the trunk, we dutifully returned stateside, where the Border Patrol agent helpfully asked how our visit to Canada was.


"Well," I explained, "we never made it more than 200 feet in-country. The Canadians tore my car apart looking for drugs we didn't have and then said we couldn't come in without $200 cash."


"Sounds like a raw deal to me." I nodded vigorous agreement, while thinking these guys had probably been smoking cigars and laughing at me while the RCMP had been deconstructing my car.


"Could I ask you to pull in over here? We need to search your car for drugs; it looks suspicious."


The only good thing I can say about the Americans is they had dogs. Their search only took 90 minutes.

Photo of the Day: "Eating with Your Mouth Open"


Nikon D90, Nikkor 18-105VR, 18mm (!), f8, 1/250 sec, ISO 200, Program exposure mode, Center weighted meter, auto white balance.


The first rule of shooting wildlife is to get closer. How close? Well, that was shot at 18mm. I'd guess I was about four feet away. Zoom in to 105mm, and this is what you get:



Friday, August 27, 2010

Briefly: 1973 Chevy Nova – “Slow Go” or "The Stripper"

I once had a 1973 Chevrolet Nova sedan.




No, not that one. Replace the wheels with steelies, subtract the racing stripes and V8, add about 400,000 miles and lots of rust, and then you're starting to get the idea.


If you thought Rusty was Rusty...


The Nova was the epitome of basic transportation: 250 cid straight six, Powerglide two-speed autobox. No air, no panel vents, no FM, no power brakes or steering. A real stripper.


I think I acquired it for $150. As a rule of thumb, I hold that any car that costs less than the fuel you put in it over the course of six months is a good buy. (A friend once said that anything under $1,000 that runs is a good buy, but I think he was setting the bar too high.)


If the 250 sounded like it had been rescued from a grain truck, that's probably because the 250 did see duty in trucks. In a flight of what can only be described as insanity, I used a coffee can to install a glass pack on the exhaust, dreaming of some day running split manifolds and duals. In my defense, glass packs were cheaper than real mufflers.


There were problems with the brakes. I'm not sure what these problems were, but they necessitated planning stops by calendar. This was not a rhetorical concern, as the 250 running through two forward speeds could still achieve 80 mph. Downhill. With a tailwind.


I was attending Morningside College in Sioux City, Iowa, when I purchased the Slow Go, and transfered to the University of Iowa (and my parents' home and cooking) shortly thereafter. It was then time to make the 330 mile trek to my folk's home in Lone Tree, on the opposite side of the state.


By this time I had concluded that only the right-front brake was working at all, and only then in the best of conditions. The shocks were shot, so a stab on the pedal would send the front end into a dive and the whole works rotating around that right-front end. With bias ply rubbers in back and (iffy) radials on the front axle, you could induce nauseating effects with thoughtful use of the two pedals.


Eventually I took to using reverse to get slowed down, which created new issues. The Powerglide never complained much, but the engine was unhappy with the arrangement. Like driving an unsynchronized manual, I discovered something akin to double-clutching worked best: shift from Drive into Neutral, give a carefully calibrated amount of gas (hint: lots), and then drop into Reverse.


It was the only way the Slow-Go was doing any burnouts.


The frame was such a rotten mess I swear you could feel it bow when this was done at above 35 mph. The u-joints also registered a degree of distress.


In the hands of a novice driver the 250 likely had many more years left in it. But as an enthusiast driver, I began to exact my toll on the old mill. In the best style of racing, I installed a mechanical gage cluster on the cowl. If I allow myself a moment for the (oil smoke induced) haze to clear, I think I installed it on the outside because I didn't want to be bothered with routing wires and tubes through the firewall. And damnit, it looked sexy. Sexy as in the 24 Hours of LeMons sexy.


Somewhere I have photos of the setup, unless common sense and common decency kicked in and I burned them.


Due to technical concerns too mundane and difficult to diagnose, the Slow-Go also had a bit of an overheating issue. As a result, it smoked, and used oil about as quickly as it used petrol. (A remarkable feat!) One morning I pulled into the UI library parking lot and noticed with some interest that the temperature gage had circled to the point where the zero-needle was impeding its progress.


A check of the important fluids revealed nothing. ...As in no coolant and nothing on the dipstick. (Please hold any dipstick jokes.) Not being a fool, I knew better than to put cold water into a hot (and totally dry) coolant system, but I did add oil.


I was concerned after the fourth quart: did I have enough cash? Should I get the oil level to the point where it registered, or eat lunch? I knew then I should have saved money and bought by the 55 gallon drum.


Several hours later, after learning much about rhetoric, I began dumping water into the radiator. It made curious popping sounds and steamed a bit.


Iowa City and the UI campus is about 15 miles from my folks home. Two quarts of oil later, I was there, in time for a late lunch! After a few squares (thanks, Mom!) I scratched my forehead. Didn't I just put four gallons of water in here? Could I have spilled that much?


In the end, I'm unsure whether the Slow-Go was possessed of fantastic fortitude or if I was simply smart enough to know when to pull the trigger. A few days after the oil and water, I purchased a 1983 Caprice and a few weeks after that I traded the Nova's Powerglide to a demo driver for a 700R4 overdrive automatic for the Caprice.


The Caprice ended up wet, but that's a story for another day. The Slow-Go went to the great scrap heap in the sky. For what it's worth, it never let me down.

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'"