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Spurred on by this post, I added a page about exposure to the Tips & Tricks gallery on my main website. It can now be found here, and covers what the camera is doing, what you’re after, and how to achieve what you want. Exposure isn’t a simple subject, so don’t expect a quick explanation, but hopefully this will help you understand it if you need help. Take a look and see what you think! For some time now, I’ve been playing with several ideas about introducing school kids to critical thinking, because I feel it’s a trait that’s sorely needed, and sorely lacking, in the US today. It doesn’t help that I have no educational background, no relation to schools, and no connections to anyone that does – working in a vacuum is probably not the best way to go about this, which is why I haven’t been pouring a lot of effort into it. You’re reading exactly where the majority of my efforts go. Something I read recently caused me, just an hour ago, to realize that something else could be added. Skeptics and critical thinkers have a lot of resources, and there’s a commonality to much of it – some of this is owed to Carl Sagan, who outlined a great collection of information in Demon Haunted World. There are lists of common fallacies to thinking, and some contribution from the scientific method and its practices to eliminate bias and error. I don’t recall ever running across this one, however, but it strikes me as a good one to include. I was reading a book about Richard Feynman’s life, who’s best known for his work on understanding quantum electrodynamics, as well as being a bit of a character and an enthusiastic science educator. He was directly involved in the Manhattan Project, the program that developed the atomic bomb, and he later reflected on the ethics of his participation in this. When he was recruited around 1942, Germany was a fierce threat to Europe and, perhaps, even America, and it was believed they were hard on the trail of their own atomic bomb. Feynman, like the majority of Americans at the time, felt obligated to do his part in halting the Nazi tide, and horrified at the thought of such a powerful device in Nazi hands. Before the Manhattan Project reached fruition, however, Nazi Germany collapsed, and the threat from that quarter effectively vanished. This didn’t really change the project for Feynman, and apparently not for anyone else. To all appearances, by this time (several years of constant involvement in,) it was both an overriding goal and a puzzle to solve, and it did not occur to Feynman that the reason he was involved in it in the first place had vanished until long after the bombs had been used on Hiroshima and Nagasaki. The point I’m making isn’t about the ethics of nuclear weapons, or about what should be someone’s proper motivations. I’m more looking at how we may get involved in something for the right reasons, but once committed, we change from having an overriding goal to treating things as a challenge to our abilities. We sometimes make a decision, then put that factor entirely out of our heads as a “done deal” and proceed towards meeting this goal, without evaluating whether the goal remains, or is worth the time, effort, money, commitment, or emotion we are putting into it. Most times, I think we do this with minor projects – I suspect everyone can remember a special occasion they were trying to make “just right” and ended up getting terribly stressed over, without realizing that such occasions are usually to relieve stress. But Feynman’s words brought home that this is probably a very common trait, and one that we should be aware of. It pays to step back, routinely, and look at what we’re trying to accomplish from a distance, to maintain perspective. It’s valuable to keep the reasons why we do things firmly in mind, and to recognize that these can both change, and may only be worth a certain investment anyway (replacing the washing machine might be expensive, but after four days and a significant amount of emotional turmoil trying to fix it, maybe it’s worth the money?) And it’s important to recognize that our minds shift gears, and small goals or advances take over the importance from larger ones, while masquerading under the rational decision that started the process. I suspect gamblers labor under this all the time, convinced that one more attempt will justify the time and money invested already. I know I’ve done it with photography projects (I just recently threw out a camera strobe project I started years ago to save some money, which I replaced with a manufactured unit just a few less years ago when it never worked as planned.) We can be reluctant to abandon a puzzle unsolved, or a project uncompleted, but if they’re not fulfilling our larger goals reasonably, we should be able to see this for what it this. We must remind ourselves to take the time to look, though. One of the more interesting things about paying attention to new science releases is watching our knowledge grow. Bearing in mind that many of the books that I read growing up were not published that year, I’ve watched our knowledge about the age of the universe, the origins of the planets, and even theories of where our moon came from get changed and solidified as new info poured in from space exploration. I got to see man walking on the moon, Skylab, Viking, Mir, watched the shuttle develop… it’s a trip. And so is this. A couple of decades ago, astronauts reported seeing flashes extending upwards from the tops of thunderheads, confirming a few reports from airline pilots of the same thing, which had been roundly dismissed by meteorologists at the time – there was no mechanism nor reason for lightning discharges to travel upwards into the rarefied atmosphere.. Eventually, both photos and video were obtained, from shuttle flights and residents on the various space stations, and the phenomenon gained more attention. Just days ago, it got a lot more interesting. The Fermi Gamma-ray Space Telescope has been monitoring gamma ray bursts from all directions since its launch, and one of the directions it was receiving rays from was the tops of thunderstorms (it was intended to be monitoring space, but hey, you pay attention to whatever you get.) Now, they got something even more: direct evidence that the gamma rays produced by thunderstorms are giving birth to antimatter.  No, this isn't antimatter nor gamma rays, but you gotta give me credit for a cool illustrating image anyway... If you remember your physics (I just barely know enough to get all this,) antimatter is rare, and on contact with normal matter, they react and annihilate each other with a tremendous burst of energy for their mass. Science fiction back from the fifties to the seventies was full of uses for antimatter, but it’s not exactly easy stuff to handle, and it takes a lot of energy to produce in decent quantities – we generally use cyclotrons and particle accelerators (like the Large Hadron Collider) to create just a smidgen of it, at a ridiculous cost that makes it impractical to consider for those uses. Here’s the cool part. The Fermi telescope registered it all because the antimatter followed Earth’s magnetic lines, and just so happened to be whipping past in this natural highway just as Fermi was. The antimatter contacted Fermi and reacted with electrons orbiting atoms that made up Fermi’s structure. The resultant burst of energy, also a gamma ray, registered on Fermi’s own detectors. In other words, Fermi detected its own “blood” as it was shot by a positron stream. And not once, but twice, as most of the stream whipped past/through, hit a “mirror” point someplace downstream in the magnetic field line (I don’t pretend to understand this,) and came back past again milliseconds later. Fermi was shot coming and going, struck by both the initial round and the ricochet. In true movie hero style, Fermi is plugging away with two infinitesimal bulletholes in it (actually, more than that – Fermi has detected antimatter five times now, and the collision was likely from a stream of positrons rather than a single antibullet.) Don’t let me give you the wrong idea – we’re still talking teeny tiny here, and Fermi has undoubtedly taken more damage from colliding with interstellar dust than those antimatter bursts. It’s startling the amount of energy that’s routinely being discharged here, and interesting to consider the process. Atmospheric temperature differences and humidity create charged areas within storms that discharge as lightning (it’s still not really known exactly how this works,) and this can create an electron flow upwards. The electrons accelerate, and contact with atoms emits gamma rays. Subsequent contact with atoms by these gamma rays creates an electron/positron pair, and subsequent contact of those positrons with electrons again creates gamma rays, again. And we detect the gamma rays by the energy they dump into electrons. It seems very circular, but really, electron interaction with energy is key to damn near everything – you’re reading this through a much more convoluted path utilizing a few trillion electrons. We should have a National Electron Day… Thanks to Jen at Skepchick for the link. I have a book entitled, “Space Shuttle: The First 20 Years” which details the shuttle missions from the perspective of the astronauts. It’s from the editors of Air & Space/Smithsonian magazine, is definitely a cool read, and provides plenty of photos. One in particular caused me to stop and stare at it closely. It’s reproduced below, photographed directly from page 143 of the book, the only place I have found this image. For those of you who are very sharp-eyed, the distortion comes from the original, the wide-angle lens used for the image, and not from my shooting with the page leaning away from me…  Credit: Scott Andrews, © Air & Space/Smithsonian What you’re looking at here is Discovery on the launch pad, obviously well before launch time (there are too many people around,) but I have no idea what mission or even which of the two pads, 39-A or 39-B.The big grey platform under the shuttle is the pad itself, still atop the crawler (the lower half, separated by the dark line) that brings it from the Vehicle Assembly Building. I’ll have more on that shortly. To the left of center, there’s a massive structure supported on the left side by a couple of columns, or seemingly so – the inner one is actually a light pole and well in front of the structure, not connected at all. This whole structure, hinged pretty much smack in the center of the image and supported by wheels on the bottom of the column, can swing closed over the shuttle while it’s on the pad, allowing for payload work just before liftoff. You can see a long white section that encloses the payload bay. And something else. Look at the dark spot in the lower right corner of the payload enclosure area (on the structure, not the shuttle itself.) I’ll give you a closer look.
Yes, that’s a door, and yes, the scale and the proportions are right, it would appear. There’s just no reason for anyone to be there, I would think, and it’s something like a ten or twelve story drop not far ahead of him (of course, it has to be male.) I started looking at every image I could find of the launch pads, and have never seen anything resembling this in any other photo. See for yourself, here (sans the crawler,) and here (a wonderfully detailed image from someone’s vacation shots – I can’t find their name on the site, just igbarker.com.) And while I’m at it, this is a shot of the whole structure closed over the orbiter, and I think this is an image of a payload being prepared for lifting up into the structure, before being slapped into the orbiter itself. The only thing that has me hesitant is that there is another person in the image I reproduced at top (not visible at this res,) and he’s in a T-shirt – the daredevil above looks like he’s in heavy clothes. But now I’m on a quest to find out more. Anyone with any ideas should feel free to write me directly, or comment below.
Depth is one of those things that is subtle, but very effective, most especially in landscape photography. Drawing the viewer into the photo, making them feel that they have a window into your image, rather than a flat “painting,” can give a much better impression. Photographs are, by nature, two-dimensional; you cannot change viewing angle for your monitor right now and get a different perspective, or dodge to the side and see what was hidden behind a tree. But we can fool the viewer into interpreting depth in our images, and this makes them more dynamic. Many beginning photographers take “straight on” images, lining their friends up together in a wall in front of the camera and shooting at eye level – this is what makes snapshots. But if you think in terms of providing depth to the image, you can create a much better photo with only a tiny amount of effort. We read minimal clues when we look at images, things like objects getting smaller with distance, parallel lines appearing to converge (think roads and railroad tracks,) and a very sneaky one, the curvature of the view as we look downwards versus straight ahead, as seen here. Going for a lower vantage point and a wider-angle lens (I believe this was 24mm on film, which is 15mm on most digital SLRs,) we seem to be seeing straight ahead in the center of this image, but actually downwards into the water towards the bottom of the frame – and we really are, due to the optical effect of wide-angle lenses. You can enhance this by aiming slightly downwards to bring more of the foreground into the image, to make that distance and change in perspective apparent. If you asked most people what the subject of this image is, they’d say, “the waterfall,” but that only takes up 15-20% of the image. The subject is more the setting itself, the placid pool in the rocky alcove, and the waterfall only adds charm rather than taking over the image. For this, I used a small aperture of f22 for a high depth-of-field, keeping the very close stones in the bottom of the pool, as well as the distant waterfall, in tight focus. This provided the added effect of blurring the moving water, since I needed a slow shutter speed to let in enough light past that small aperture for a proper exposure. Naturally, the camera was on a tripod for this. But you can induce depth exactly the opposite way, too, by using a wide aperture and thus cutting your depth-of-field down very short. This means that subjects within your frame with only a small separation of distance between them can have different focus – your main subject is in tight focus, but something only a short distance behind it or in front of it goes out of focus, making the idea of depth even more distinct. You can see an example of this (and more about how to do it) on this page. You can also exaggerate this effect by using a longer focal length, or by getting very close to your subject. Both of these result in higher magnification, and depth-of-field drops shorter with more magnification, plus it gets shorter with closer focusing distances. Alternately, wide angle lenses give the greatest depth-of-field, most especially at long focus distances. Anything that either draws a line or shows distinct reduction with distance perspective works very well for inducing depth in the image – the two fisherman in this image demonstrate this nicely. You can also use, as mentioned above, roads, fences, and even fields of distinct objects like flowers, which will give the viewer specific shapes to see reducing with distance. Getting closer to any of these will exaggerate the effect, making them loom larger in the bottom of the image and increasing the disparity of sizes within the frame.
By the way, I just wanted to point out that the two images I’ve used so far have their own balance, a subtle emphasis towards one side or another, and thus they were placed alongside the text appropriate to leading into the text, rather than away from it. Meanwhile, if you remember the Rule of Thirds post, you might notice that the roadside image hews pretty well, placing the road in the lower third and the moon almost precisely at the focal intersection of the upper left cross – but the waterfall image doesn’t fit well at all, breaking the rule more than it fits. So, did you like one better than the other before I mentioned this? It’s no use asking you to consider them now that I’ve tainted your subconscious with what’s “good” and “bad”…
As another aside, I mentioned in a previous composition post that being aware of the clouds can make a difference, and waiting for them to be right for the subject is time well spent. For this one, I waited for the clouds to provide a break around the peak, because I found the image stronger with a blue sky background rather than a cloud back there, and it provides some contrast to the reds and oranges of the foliage. Three of my favorite examples of depth in images (well, my own images, anyway) can be found here, here, and here. As with any compositional element, there are circumstances where it works better, and others where it does not, or isn’t really needed. It’s an easy thing to play with, and can be induced from plenty of photo opportunities, so have fun with it! If you had any difficulty with this site in the past day or two, I apologize. Some settings got skewed I believe, and it took me a while to recognize them. I think everything is back to normal now (and upgraded to boot.) If you’re still having issues, try to reach me on the Contact page above, or through my main website Feedback page. I’ll be back with real content shortly. Thanks for your patience! [Sorry, I’ve been away for several days and come back with a 3,100 word exposition. Is that making up for it or being sadistic?] In watching the discussions on a couple of forums recently, and knowing how things have gone in several of my own discussions on religion, a couple of points have made themselves clear. These were things that I suspect I have understood subconsciously for a long time, but haven’t really articulated until now. The first is the arbitrary and selective application of standards, or “rules of evidence” if you will. This is paid homage to, very subtly, in a fairly common debate point among atheists: “I simply believe in one less god than you do.” The point is, there have been literally thousands of gods and supernatural beings throughout history, in most cultures and with a wide variety of properties, powers, and forms. Virtually none of them are taken seriously by anyone, no matter how devout, except for one (or one set): the one that the devout happens to follow. All of the rest – thor and quetzalcoatl, gaea and janus and raksasa, bast and tsetse bumba – are all considered mythology (thanks to godchecker.com for a couple of these.) But if you ever ask for the distinction between myth and god, and believe me I have, you never get a useful answer. There never seems to be any rule, standard, test, or evidence that can be made to apply, to differentiate one (the “true” god) from another.
So instead, I’ll provide a quiz question (mostly because I feel some need to put something up here today.) Relying on this chapter, refer to the image at top. I was waiting for the gusting wind to blow some loose snow across the frame to lend a little atmosphere to the composition, so I was holding the same framing in the viewfinder for several minutes. Can you tell me why, in order to do this, I had to keep shifting my vantage point? The answer lies immediately below – click and drag across the blank space with your cursor, highlighting the text to read the answer. I’d offer a prize to the first person to e-mail me with the correct answer, but considering the dearth of comments, I might be waiting a while. So instead, here’s the explanation: Did you get it? Whether you did or not, check this out the next opportunity you get – its a neat thing to watch happen. Thanks for visiting!
Above, a mockingbird realizes some more calories are needed to keep warm, and snacks on some late berries. Birds are a good subject in wintertime, since they remain active but become much easier to spot, and generally stand out well against the snow and bare branches – much better with brighter light than this, though. But sometimes, you can do something a little different. The clouds were clearing tonight, allowing a few scattered stars to peek through. A long exposure (in this case 20 seconds) can bring up the fainter stars, set against the snow-covered branches illuminated by the streetlights. I chose darker branches for this image to emphasize the stars more, and to allow more of an impression of what you’d see gazing up from a dark locale. Right now I haven’t determined if the constellation Orion is obvious enough to most viewers, or if the three belt stars are more confusing in their symmetry and I should have stayed with just a random star patch. |
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So our next topic of discussion on the subject of composition is “depth” – what it does and how to present it.
This leads us to another compositional element: leading lines. Our eyes naturally follow implied paths, which curiously could very well be an evolutionary trait, helping us spot the easiest passages and game trails. But in images, it means we track such lines with some expectation of seeing something at the end of them, and as a photographer you can use this trait. Here, I had plenty of positions to take on this road, but I chose this particular side because it placed the moon almost directly above the converging lines of the road and verge, and even has some subtle help from the treelines. Timing it to let a car go past gave greater emphasis to the road and provided some light down there – otherwise, if I’d exposed to let the moon light up the road surface, the moon itself would have been far brighter and glaring. Overall, the subtle message is a destination under a brilliant moon… gosh, look at me, I’m playing around being artsy. You don’t even need a subject at the end of your leading lines, if you want there to be mystery or even the idea of going nowhere, if that’s your message. Just remember that the viewer follows them, so use them judiciously.
Getting back to depth, there’s a pair of effects illustrated here that can be used as well, in the right conditions. Atmospheric haze increases with distance, so images over a significant distance can show depth if you capture the bluish haze that separates, for instance, distant hills, and you can select light and weather conditions to enhance this, such as early morning as the fog is lifting. Notice how there is a distinct foreground row of trees, with the hill and the peak behind them in a slightly different color due to haze. Additionally, autumn colors not only provide a rich, pleasing palette, but often serve to distinguish individual trees from one another, once again increasing that feeling of depth. Had this image been taken in high summer, the trees would all have been the same color and would blend together, reducing the idea of depth. But here you can almost judge exactly how far away the peak is, can’t you?
