Tag Archives: photography tips

June 14, 2013 · 5:35 am

Photo Tip Week — Controlling Depth of Field


An explanation on why today’s post may be a tad familiar:  My oldest daughter is in town, as well as four of the grandchildren.  So, being tied up (or, in this case, strapped to a table saw as we play, “Pit and the Pendulum”), I’m going to do a rare reblog-week using three of my most popular photography tip blogs.

On Monday we did The Rule of Thirds.  Wednesday we took pictures in available light photography without a tripod.  Today we’re going to look at controlling depth-of-field using the aperture control on your camera.

And now, the encore presentation of: Getting Out of Your Depth (of Field)

Depth-of-Field—It can either work for you or against you . . . if you do not fully comprehend what it does and how to control it.  So, why leave such vagaries to chance?  Today we’ll discuss ways to make depth-of-field work to your advantage.

Maximum depth-of-field will present objects in both the foreground and background in the sharpest possible focus.  Minimum depth-of-field is used to keep a single subject in sharp focus while deemphasizing the distractions by blurring anything in the foreground or background that is not germane to the subject.

Landscapes—Here you usually want maximum depth-of-field, allowing you to capture in sharpest possible detail everything from middle distances out to the horizon.

Portraits—Generally speaking, these call for a very narrow depth-of-field.  You want to have your subject in sharp focus, but if the background isn’t blurred then it will compete for the viewer’s attention.  This may not be the case if you want your subject framed against the backdrop of a noted landmark such as the Eiffel Tower, or with the Grand Canyon residing in the background.  In those cases, your “portrait” shot will need to be more like a landscape.

Still Life Photography—If your subject is a single flower, think of your photograph as a “portrait” of that flower and blur the foreground and background accordingly.  If your subject is a collection of brightly colored fruit, a large bouquet or a bed of flowers, then maximum depth-of-field may be required to bring out the highest degree of visual impact.  But in this latter case, you may still want to find a depth-of-field middle ground to blur background distractions.

Controlling Depth-of-Field (DoF)—There are many ways to control this aspect of photography.  Generally speaking wide-angle photography has more DoF than telephoto settings; smaller camera sensors give greater DoF than do larger sensors at the same lens aperture settings and relative focal lengths (think pocket camera versus DSLR here); and wider apertures narrow the DoF while smaller aperture settings increase the DoF.

Inherent to the above paragraph is the understanding that you’re going to have a tougher time reducing your DoF with a small camera than you would if you have a camera with a larger imaging sensor.  On the other hand, this means that a point-and-shoot will have a built-in advantage over your DSLR when it comes to providing maximum depths-of-field.  Also inferred is that if you own a DSLR and do a lot of portrait-style or other narrow-focus photography, you need to consider investing in more expensive, wider aperture zoom lenses, or perhaps even go to fixed focal length (non-zoom) lenses for some of your photographic work as fixed focal length lenses are often available in wider apertures.

The best focal lengths for portraits, whether you use a small pocket camera or a larger DSLR, are (in 35mm equivalent) in the 85mm to 135mm range, with 105mm being my personal “sweet spot” for optimum portrait DoF control.  Indeed, my favorite all-round zoom lens for everything from landscapes to portraits is a 24-105mm f/4.0 mounted to a DSLR with a full-size (35mm) sensor.  Professional photographers will go with dedicated 85mm and 105mm f/2.8 fixed focal length lenses, but I personally just can’t justify that kind of expense for a hobby.

But watch out for the extremes—You may be tempted to go with the maximum aperture available for portraits and the smallest possible aperture for all your landscapes.  Resist the temptation unless you really need it.  The widest aperture will frequently give you vignetting (light drop-off) at the corners of your photograph, and most lenses also produce a softer image when set this way (not necessarily a bad thing in true portraits, as softening helps to hide skin imperfections and blemishes).  At the other end of the aperture spectrum many lenses are prone to chromatic aberration (also known as “color fringing”), which causes different colors to focus at differing points in the photograph.  This can result in an odd, distracting, rainbow-like effect at the edge of a subject that diminishes clarity and sharpness.  Another problem associated with DSLRs set to minimum aperture is dust and dirt on the sensor.  These contaminants (which may otherwise be rendered all but invisible at wider apertures) will come into sharp focus at f16 to f22, especially against a uniform background such as blue sky.  Sure, you can edit these specs out later in post-processing, but why make your life more difficult?

Now, a little trick for even greater Depth-of-Field—

The Setup:  You have a potentially award-winning composition.  In the foreground lies a field of amber grasses with long, flowing stalks.  The background displays an impressive range of majestic, snow-covered peaks against cerulean skies.  A warmish, setting sun is directly behind you, giving both the grasses and the mountains a pleasing, surreal reddish hue.

The Problem:  Even at the narrowest aperture your lens allows, if you focus on the grassy foreground, the mountains lose their crisp focus.  If you lock on the mountains, those amber waves of grain become a blurry, confusing mush.

The Solution (for DSLRs and higher-end point-and-shoots):  Take your camera off autofocus and manually focus at a point between the foreground and background, with the focusing point biased toward the foreground.  Optimally, this focal area will be at an imaginary point one third the distance from the closest foreground subject, two-thirds away from the farthest object.

The Solution (for “consumer” point-and-shoots):  If your camera does not allow for manual focusing but does let you select from one of several available focusing points, select a focus point between the foreground and background biased in favor of the foreground as described in the above solution for DSLRs.  If your camera does not allow selective focus points, focus directly on a portion of the scene as described above—one third of the distance past the foreground and two-thirds the distance in from the background—by depressing the shutter release button halfway.  Continue this halfway press to lock in the focus (which will also lock in the exposure settings, by the way), recompose the scene, and then depress the shutter release button the rest of the way to snap the shot.

The following photographs were taken using a Canon EOS 5D with a 24-105mm f/4L IS lens.  Focal length and aperture settings are as listed.  Subsequent shots in each sequence represent in sequence a wide-open aperture, a medium aperture, and an extremely narrow aperture.  Thus, the apertures in each sequence are: f4.0 on the wide end, either f8 or f11 in the middle, and f22 on the narrow side (click on this link for my previous discussion on f-stops).

Note how the DoF increases as the aperture decreases (remember that when discussing aperture in photograph, the higher the number the smaller the lens “opening,” or “aperture”).  Also, you can see examples of the aforementioned vignetting problem in the f4 photographs in the 60mm and 105mm series—look at the darkening of the blue sky in the upper corners.

Comments Off on Photo Tip Week — Controlling Depth of Field

Filed under Photography

Tagged as , , , ,

June 12, 2013 · 5:35 am

Photo Tip Week — Who Need’s a Tripod?


An explanation on why today’s post may be a tad familiar:  My oldest daughter is in town, as well as four of the grandchildren.  So, being tied up (or, in this case, hanging inverted over a roasting pit as we play “Spanish Inquisition”), I’m going to do a rare reblog-week using three of my most popular photography tip blogs.

But it won’t be a complete repeat.  Check out the pictures for ones that are different examples from those used in the original blog.  Monday was on The Rule of Thirds.  Today is on available light photography without a tripod.  Friday will be a bit on the technical side as we discuss controlling depth of field using the aperture setting on your camera (don’t be intimidated — it’s “technical,” but in easy to understand terms).

And here is the summer rerun of: Available Light Photography Without a Tripod.

Remember M. Schwartz of Photo Clinic Fame? Well, M. has another request.  This time M. wants to know how to take pictures requiring long exposure times without a tripod.

We’ve all been there, so you know what I’m talking about. You’re inside a dismally lighted medieval castle; a deep, underground cistern dating back to the Roman Empire; a cavernous cathedral illuminated only by the light streaming through stained glass; or a mosque with an intricate mosaic tile ceiling high above.  Flash photography is not allowed and wouldn’t do you any good even if it were.  You have no tripod available.  Your only available camera is a travel zoom containing a small 1/2.33” sensor with a top useable ISO of maybe 400 . . . on a good day and then only if you’re really, really pushing it.  What the heck do you do?

Well, believe it or not, that small sensor size can actually work to your advantage in creating some really stunning interior shots using only available light and while setting the ISO to 200, 100, or even lower for optimum noise reduction.  That’s because that small sensor invariably comes packaged inside an equally small camera, and that small camera usually comes with two very flat surfaces—the bottom of the camera and, if properly designed with rear controls recessed, the back side where the LCD screen resides.  And these little travel zooms also frequently come equipped with one very important feature that negates the need for a shutter release cable or a tripod—a two- to ten-second self-timer.

But first, a rule of thumb. I know your camera says that either the lens or the sensor is “stabilized,” and that the manufacturer claims a benefit of anywhere from 1 to 3 stops.  Forget all that.  Here’s the rule:  If you’re at wide angle (less than a 50mm focal length in 35mm equivalent), don’t shoot hand held below 1/30th of a second.  If you’re at normal to mildly telephoto focal lengths (say 50 to 135mm), you should increase your shutter speed to at least 1/60th of a second.  At longer focal lengths, start looking for something to stabilize the camera if the shutter speeds falls below the reciprocal of the focal length.  Now, I know, that last one was confusing as heck.  In simpler terms, if you’ve zoomed in on a subject at the 35mm equivalent of a 200mm lens, your camera had better be telling you that the selected shutter speed is at least 1/200th of a second or faster.  At 300mm it should be at least 1/300th of a second, and so forth.  If you’re really confident with the manufacturer’s claim of, say, a 2-stop advantage with your particular camera then you can halve those times, but don’t get too pushy on it or you’ll get blurred results.

Tip One, The Ceiling: Wow.  Look overhead.  Isn’t that tiled mosque ceiling stupendous?  Now, how do I get the shot?  Set the camera’s self-timer to two seconds, the white balance to automatic, and the ISO to 100 or even lower.  Position the camera, properly zoomed, on the floor directly beneath the subject of your adoration.  Crouching low and offsetting to the side, out of line-of-sight of the lens, depress the shutter release button half way for a brief moment to allow the camera to focus and determine exposures settings, then depress fully.  Back away as the camera begins its countdown.  Wait a couple of seconds after you hear the shutter click, then retrieve the camera and check the shot.  It should be rock solid clear with no noticeable digital noise.  But just to make sure, you can zoom in on the details and see if they maintain their sharp crispness.

Tip Two, That Piece of Art on the Wall: Whether it’s a religious statue, mosaic, or perhaps even an action shot of a woman kissing a religious artifact, chances are that lighting conditions will not be conducive to a hand held shot.  If there’s something nearby upon which you can balance your camera, then great.  Set the camera as in Tip One, including the self-timer.  Compose the shot from where you’ll be placing the camera.  Press the shutter release as described before and get out of the way for a few seconds while the camera does its thing.  Voilà.  Another perfect shot.  This is getting easy, isn’t it?  You’re really starting to look like a pro.

Tip Three, That Cavernous Cathedral: I don’t care what your pastor says, this is the real reason God made pews.  Trust me.  They’re great for this next tip.  Perch the camera onto the back of the pew in front of you.  Compose and snap the shot, bracing the camera perfectly still.  If the back pew rail angles the lens too high or too low, try compensating by placing something (such as the camera’s own carry strap for instance) in a position below the camera that helps achieve the proper lens angle.

Tip Four, The Restaurant: Restaurants are big.  Even if you have a flash, chances are anything beyond ten feet is going to render as a dark, ghostly shadow in your photograph.  Worse, the table top is too low and the seat backs block the view from the lens.  Okay, now what are you going to do?  HMMmmm.  Let’s look around.  What’s that I see?  Oh, yeah, the waiter brought me a glass of water.  How convenient.  Set the camera up as previously described, including the two-second self-timer delay.  Perch the camera carefully atop the glass, making sure neither end is in danger of tipping into the glass (water and most digital cameras are loathe to mix; bad things usually happen when they do).  Compose the shot.  Use that two-stage shutter release trick from before and let go of the camera once the self-timer has activated.  Check your perfect, non-flash, available-light restaurant shot and try it again if something is amiss.

Tip Five, When All Else Fails: No church pews.  Nothing on which to balance even a small camera.  In fact, there are so many people meandering about that they’d block your shot anyway.  My goodness.  This is a toughie.  Actually, it isn’t, but don’t let the institution curator catch you doing this or they’ll go ballistic.  Stand with your back to a wall or column and hold the camera high above your head.  Now, push back until the camera’s backside is firmly braced against the wall or column.  Do that two-stage shutter release and hold the button down while you count off three or four seconds.  If you had the camera firmly braced and didn’t move any, your shot will be just as blur free as with the previous tips.

But by blur free, I’m not referring to moving objects. Just because your camera is rock-stable doesn’t mean that your subject is.  People moving about the scene can and will blur, but that’s not necessarily a bad thing.  It can add an artistic feel and a really great contrast to the intricate details lying beyond them.  You’ll need to decide for yourself on a shot-by-shot basis when this occurs.  Just don’t automatically delete a photograph because something moved and blurred in the foreground.  You might actually have a winner despite that perceived “flaw.”

Below are photographs that were all taken using the aforementioned techniques. None have been post processed in any way, not even for straightening which is a common fix often needed whenever you have to resort to this type of shooting.  They are all displayed here as they came straight out of the camera just to show you what to expect.

Comments Off on Photo Tip Week — Who Need’s a Tripod?

Filed under Photography

Tagged as , , , ,