Shutter Speed

Shutter speed is the second side of the Exposure Triangle. When you are in the Manual Mode anytime you change the value of any side of the Exposure Triangle the photo you take will get either brighter or darker. Last time we looked at ISO. If you increase the ISO setting from 100 to 200 the photo will be one stop brighter going from 200 to 400 will make it another stop brighter. OK, now it's time to look at shutter speeds. Imagine your lens like a pipe with water coming out and pouring into a bucket. More water in the bucket is like more exposure and more exposure means a brighter image. Our shutter acts like a faucet on the pipe. If we open the faucet for one second we will get a certain amount of water (brightness) in the bucket. If we open the faucet for two seconds we will get twice as much water (or brightness) in the bucket.

That's how shutter speed works in a nut shell. The longer the shutter is open, the more light is allowed to strike the sensor, and the brighter the image will be. Let's see what those shutter speeds are. A typical DSLR camera will automatically expose a photo for up to 30 seconds. If you use a speed that slow (long) your camera better be on a tripod. There are even ways to expose a photo for minutes, or hours, but right now let's assume your holding the camera in your hands and you want to point it at something and take a photo. Now what shutter speeds are we talking about.

Most photographers can learn to hold a camera steady enough to shoot at 1/60 of a second. From there as the light gets brighter, or the lens gets bigger around, the shutter speed can increase to 1/125 second, 1/250, 1/500, 1/1000, 1/2000,and maybe even 1/4000, or 1/8000 second. Back to "stops" again each of those speeds is one stop less than the one before. For example 1/2000 of a second is only half as long as 1/1000 of a second and therefore will expose only 1/2 as much. Remember 1/2 as much is one stop less (darker) and twice as much is one stop greater (brighter).

1/320 Sec. Stops 'em on Second Base

When we looked at ISO we looked at what else happens when we change it. With ISO remember as the ISO gets higher, while the image gets brighter, the noise gets greater. Well, what happens when we change shutter speeds? The less time the shutter is open the darker the image (exposure) but the other effect is that if the shutter is open for a shorter time movement has less effect. What movement? Well if I'm holding my camera very still and take a photo of a speeding auto, a slow shutter speed will show me a photo of the car as blurry because my shutter was open for 1/60 second and during that time let's say the car moved a foot so I see a one foot long blur. If I shoot the same car at 1/1000 of a second the car will move less that 3/4 inch so I still have a blur but 3/4 inch is much less noticeable than a foot. If my image shows the entire length of the car and space in front and behind it then 3/4 of an inch may not even be visible and I will have a very sharp image.

At 1/5 Sec. Truck Shows it's Moves

The car is a example of subject movement. The other movement we worry about is camera movement. You can not hold a camera perfectly still. A telephoto lens adds to the problem since as it magnifies your subject giving you a close up of a deer at 50 yards,  it also magnifies your camera movement. So, a higher (faster, shorter) shutter speed reduces blur from camera movement as well as blur from subject movement. So far it sounds like faster shutter speed are better, and in many cases that is right. However, many things we photograph do move and we are taking still photographs. If we look at an 8 x 10, glossy, full gcolor photograph, hanging in a frame of our favorite NASCAR moving at 120 miles per hour how do we know it's moving at all. The only way a still photograph can imply motion is if something is blurry. If as in my first example I put my camera and use a slow shutter speed everything will be sharp except the moving car(s). Anyone looking at the photo will know that the car was moving and the longer the blur the faster it will look.

This car was moving about 30mph and the camera 1/30 sec.

Wait a minute, this is my favorite NASCAR, I want it to be sharp not blurry, but yeah, I want people who look at my photo to know it was moving 120 mile per hour, so now what? Combine and synchronize subject movement and camera movement. At right with the cameras shutter speed set at 1/30 sec I aimed at the car when it was 3/4 of a block down the street. I followed it as well as I could and when it was nearly in front of I pressed the shutter. I kept following the car as the exposure was made to keep it as sharp as I could. Above we have a sharp image and a blurred truck and here it's a blurred image with a sharp car. Two different was of implying movement in a still image.

Another use of a slow shutter speed with no noticeable blur is seen here in a full 30 sec. shot of the Hudson river. What the long exposure creates here is a smoother, more peaceful river than it would appear in a faster shutter speed. Learn to use your camera's Shutter Speed Preferred Mode (S or Av) and experiment with various speeds.

Very important: "There is no cost to digital experimentation", delete what you don't like.

What is ISO?

There are three settings on your camera which control exposure they are ISO, shutter speed, and aperture. Together they are frequently called the Exposure Triangle. ISO refers to the International Organization for Standardization (I know that should be IOS). I've looked and I have not yet found a language in which the name would come out ISO but it is what it is and we've dealt with it since 1947.

In photography it refers to sensitivity to light. In film days we bought 100 speed film, those of us who shot slides sometimes shot 25 speed film. If we were going to shoot inside in dim light we bought 400 speed film. In those days the film was usually labeled ASA (the American Standards Organization) and at a time I've lost to memory the boxes began saying ISO instead of ASA. The numbers didn't change. ASA 100 and ISO 100 are the same speed. ISO and Speed measure how sensitive the film is to light. The higher the number the more sensitive the film.

Remembering "What is a Stop?" ISO's double to make them one stop more sensitive. If you are shooting at ISO 100 and you change it to ISO 200 (this only works in Manual mode) your picture will be one stop brighter; change to ISO 400 and it will be 2 stops brighter. In automatic modes changing the ISO causes the camera to automatically adjust the shutter speed, aperture or both (these being the other two sides of the Exposure Triangle) and the image stays the same exposure (brightness).


In digital photography the numbers still have the same meaning only now it refers to how sensitive the digital sensor is to light not the film. In film days if we wanted more sensitivity we removed the film from the camera and put in a more sensitive film. In digital cameras we can change the ISO for each shot if we want to, because there is no film to change.

To truly change the sensitivity of the digital sensor we would have to replace it with a more sensitive one. Every sensor has a "native" sensitivity that cannot be changed. So why do we think we can change it? What comes out of the sensor is an electrical signal and electrical signals can be amplified. If we are listening to music and want it louder we "turn up the volume". If the picture is not bright enough we "turn up the volume". In dim light the signal coming from the sensor is weak so we amplify it which unlike sound doesn't make it louder, it makes it brighter. We have "effectively" increased the ISO.

The next question is: "How much can we do that?" and that answer changes as improvements are made in newer camera models and also with the price of the camera. Here is the problem; every electrical circuit contains two types of information, "signal" which is what we put there and want there, and "noise" which is what we don't put there and really don't want there but it's a physics problem, where there is signal, there is also noise. In digital photography the signal is the picture and noise shows up, mostly in dark shadow areas, as colored flecks or spots. When we amplify the signal, the picture gets brighter. But we can't just amplify the signal, we also amplify the noise and it gets worse. we get more colored flecks until it gets to the point where the image is worse than we are willing to allow, and then we have passed the "How much can we do that?" point.

So where can we expect to find the point. Most DSLRs on the market have a "native" ISO of 100, some start at 200, also most have little problem getting to 1600 ISO without excessive noise. There are quite a few cameras that will go higher than this and the highest speeds are frequently called extended or expanded range which means your images no longer appear "noise free". The Nikon D4 as an example will hit 12,800 ISO without using the expanded range, but it is a $6000 camera and for that money the expanded range will take you to 204,800.

The series (above right) is the section outlined in yellow (left) of photos that were taken with a Nikon D200 and from the top down were shot at ISO 100, 200, 400, 800, 1600, 3200 each is one stop faster than the previous. The 3200 was an extended range ISO.

What does this all mean in practical terms? The photos were taken on a cloudy day inside and the room was not very bright. At ISO 100 the shutter speed was 1/5 second and probably could not have been hand held. In fact until the ISO was all the way to 3200 (that's 5 stops faster) the shutter speed was too slow for someone my age to attempt without a tripod. The bottom line is that higher ISOs allow faster shutter speeds and save you from setting up a tripod for many shots.

What is a Stop?

Origin of the Term

I would like to explore exposure more. In several places in earlier posts I have used the term "stop". For those new to DSLR style photography and making adjustments yourself, the term may puzzle you. If you look up the word "stop" in the dictionary you may find a reference to "photographic stop" but I had better luck looking up "detent" (which my current spell-checker says is not a word). Imagine a wheel with small notches like the one at right. On top rests a spring with a vee shaped end which fits the notches. When you turn the wheel it will try to stop each time you reach a notch. These notches are called detents and sometimes "stops" with them you know exactly how far you've turned the wheel and you can find the same spot again any time.

You can also stop in between if you want to.

Use of the Term in Photography

In photography one stop more exposure is two times the exposure and one stop less exposure is 1/2 as much exposure. The question now is why was double and half chosen as a normal difference between exposures. Double seems like a long way. Look at the three images below. The center one is what I chose as the best exposure. The one to the left is twice the exposure or one stop greater and the one to the right is 1/2 the exposure of the center one.

The difference between the exposures is a comfortable difference to work with. It is noticeable but not extreme. As with the wheel above your camera can be set in between stops if you feel that a whole stop goes too far. Most cameras adjust to 1/3 stops and not many photographers find a need for a finer adjustment than that.

There are three adjustments on your camera that affect the exposure so come back and we'll tackle them one at a time.

White Balance

Well, of course we'll start off with "What is white balance?" If you walk out on a bright sunny day and someone hands you a piece of printer paper, it looks white. Later if you are sitting on your couch and the lamp next to you has a 60w bulb in it and you are handed the same piece of paper it will still look white. What your camera notices is that the paper looks a lot bluer outside and very red/yellow under the 60w bulb, under florescent lights it looks much greener. Your brain is so used to these color changes that it compensates for the color differences and the paper usually looks just as white in all the different lights. The White Balance in your camera must be adjusted to compensate for these differences in light color. Most cameras are set on Automatic White Balance and like most other camera computer controlled operations it works very well. But like exposure, automatic is not necessarily "correct" and correct is not necessarily what I want. Your camera will let you set the white balance to the type of light: sunlight; cloudy, shade, incandescent, fluorescent, open shade. Many

cameras will allow you to set the preferred "color temperature". I don't want to get to deep into that subject but briefly: color temperature is measured in Degrees Kelvin. Daylight with the sun shining is usually about 5500°K, that reddish/yellowish 60w bulb more like 2500°K, and open shade about 10,000°K, or the lower the temperature the redder the light and the higher the temperature the bluer the light.

Take a photo on a cloudy day with your camera set to Automatic White Balance, then reset the camera to Cloudy and compare the two images. Usually the shot set to Cloudy will be redder than the other. Just to add confusion here artists refer to redder light as being "warmer" and bluish light as being "cooler", the opposite of color temperature numbers which go down for red and up for blue. This means that when you set your camera to Cloudy and the image looks a little redder we say that the image in "warmer". Photos of light skinned people usually benefit from a little added warmth, the skin just looks healthier than the sometimes bluish color of photos taken in the shade. Anytime you are not pleased with the color of the image you see on your LCD try setting the white

balance to match the light you are shooting in. Also try setting the white balance to the WRONG setting to see what happens. If I set my white balance to Incandescent and take photos on a sunny day the photos will  be very blue. Now if you use Exposure Compensation and set the exposure to say -2 the photo could look like it was taken by moonlight.

The photo here (Granddaughter Saylor) was taken in the shade during the day. The color temperature was probably about 6500°K but the camera calculated 4300style="background-color: white;">°K and the photo at the top was created. It's not bad but is a little on the cool side. Since the photo was taken in the camera's RAW mode the color balance is actually set in the computer not in the camera so I was able to change it. In the second I set the color temp to 6500°K or, the approximate temperature of open shade and created the second version which is much warmer (that's redder) and a more attractive skin tone. Just to fill out the group I set the color temp to 2850°K or a middle tungsten light and the image is a very cool blue.

I will get back to RAW in a later post but if your shooting jpegs (most people and a lot of pros do) remember to check the color and set the white balance to the type of light you are actually shooting in. You may be much happier with your photos.

Carnival at Blue Hour

Last night we took grandchildren to the Sharptown Fireman's Carnival. They are old enough to roam alone and I took the opportunity to do some blue hour shots. If you're not familiar with the term "blue hour" it is loosely defined as the hour before sunrise or the hour after sunset. A major advantage of blue hour photography is that you can get night shots without a plain black, nothing sky.

It's not difficult to take shots like the one at right. I wanted the look of night and I wanted the rotation of the lights and the blurred Ferris wheel to be visible. It was 7:30 in the evening and not quite as dark as the photo looks. Had I shot in "P" or Program mode my shutter speed would have been too fast to show the amount of blur that I wanted. I chose, instead, "A" or Aperture Preferred mode. In this mode I choose the aperture and the camera's computer figures out the shutter speed.

Since in this mode I was still allowing the camera to calculate the "correct" exposure, I stepped in. The camera would think "it's dark, I'll lighten it up". The photographer (me) was thinking "it's a little too bright and I want a night look so I'll darken it". I held down my little Exposure Compensation button (see earlier post) and dialed in 2 stops of under exposure. (That turned out to be a little much and I brightened it, just a little, in Lightroom). This gave me the night look I wanted, but I still had to set the aperture. I wanted a slow shutter speed so I had already decided to set the ISO to 100; and to make sure the shutter speed was slow I chose a small aperture f/22. By lining up my shot I could see in the viewfinder that my shutter speed would be 1.3 sec and the shot here is what I got.

Let's be honest here. I took this shot four times; f/8, f/11, f/16, and f/22. Since the camera's computer was calculating the exposure, the four shots were identical in brightness because the camera kept changing the shutter speed as I stopped down (made smaller) the aperture. I kept going to smaller apertures to force the camera to use slower shutter speeds, to increase the amount of blur. At f/22 I got what I wanted and stopped.

One final point. With a 1.3 second exposure ya gotta have a tripod and I didn't. This was "night with grandchildren" not "photo expedition". Sooooo there was a nice white, plastic picket fence near by and could hold the camera against a fence post (keeps the camera still) with my holding hand sitting on the fence rail (keeps my hand still) and get a sharp shot.

Some might disagree, but I think night shots are very forgiving so, try them. Generally you will need a tripod but as you see sometimes and handy stump will suffice.

Exploring Exposure

What is exposure? Well the answer is "sorta" easy, it's how dark or light the photo is. But how about: "What is correct exposure?" Now it's getting a little tougher. I'd say there is absolutely no such thing as correct exposure. So, what is it that my camera's Automatic exposure mode is giving me? Your camera is working very hard to give you a "reasonable" exposure, one that includes detail in as much of the picture as possible. If the scene contains areas that are much brighter or much darker than average or maybe both kinds of areas, there will be no single exposure that can possibly show detail in all areas of the photo. Someone or some computer will have to decide what exposure is best. Camera manufacturers have created computer programs which reference thousands of sample photos to determine what kind of scene is in front of camera, so that a reasonable decision can be made as to what exposure to use. This program and the data from those thousands of sample photos sits inside your camera and works well, very well. But lets look at the two photos below:

I shot a series of 5 photos for the purpose of merging into an HDR image. Later I began looking at the individual images and picked out two exposures that I liked by themselves. You may very well like one of these images better than the other, but someone else probably prefers the other. The top shot emphasizes the fences in the foreground and allows the end of the alley to almost disappear into the light. The lower one shows more detail in the lighter alley end and looks more "realistic". I like both of these images and there is not now, not ever going to be, a computer that can pick the one I like best.

Both of these images were touched up slightly in Lightroom, but they are essentially different because of a one stop difference in exposure. Much more can be said about exposure and I'll probably be back to say some of it. If you want to improve your exposures, experiment.

Adding the Shadow to the Post Below

I promised to tell how I added the shadow to the post just below this one after moving the figure to make her apparently closer to the viewer. She was moved down and made larger, and she was removed from her original position. Now I added the shadow.

The finished photo to the right has the shadow added but how do you create a shadow? You know that the shadow is the shape of the figure casting the shadow and if we click on the eye of the Background layer (in the Layer pallet on screen right) all we have left is the figure as seen below. While your at it click to the right of the eye to be sure that layer is active.

Create a copy of this layer by pressing [Ctrl J], then while holding the [Ctrl] key down click on the tiny thumbnail of the figure in the layer pallet and it automatically selects just the figure and does it perfectly. Look near the bottom of the tool bar and you should see two overlapping small squares. The one on top should be black and the bottom one white. These represent the Foreground and Background colors and if they are not black and white just type the letter "d" and it will reset the colors to the default (B&W). Looking back at the image which is selected the keyboard shortcut [Ctrl Backspace] will fill the selected area with the foreground color, black, and you now have a shadow that looks like the subject. Of course it's currently on top of the subject and not on the ground where it belongs. Remember, last time, I used [Ctrl T] to call up the Free Transform function which allowed me to move my figure and re-size her. Here I do it again and this time I click on the top center handle (in the rectangle which appears) and drag it straight down and off the edge of the image until my "shadow" looks about like I imagine it.

Just two little details to complete the image. While were looking at just the shadow select Filter>Blur>Gaussian Blur and drag the Radius slider to about 10. Our shadow is now a little soft on the edges just like a real shadow would be.

Shadows are not black they are the color of whatever they fall on, just darker.  Over in the layer pallet bring back the eyes of the Background layer and the layer of our figure, then be sure that the shadow layer is still selected and at the top of the layer pallet find the word Opacity. Next to it will be 100%, change it to about 50% and you will be done.

OK two more really tiny things for closing in on perfection. The shadow will be at the top of the layer pallet. Click just past the name of the layer and drag it down below the layer that contains the figure. Now click on the figure layer and, using the Move Tool, drag the figure down just a little so it's on top of the end of the shadow just as is would be in real life.

I hope you've learned something here. Please let me know. Oh and here is a new final image that was created as I type the instructions above.

A Move in Photoshop

  I found a shot I had taken about 4 years ago and thought that my wife's niece was in a position to detract from the shot. (left.) I wished I'd caught her closer to me in the slot canyon we were walking through."Then I thought "that's what Photoshop is for". This is not difficult to accomplish in recent versions of Photoshop and Photoshop Elements. The image to the right was created in Photoshop C6 and the one below was done in Photoshop Elements I treated the shadow differently, not because of any difference in the programs, but because I was playing with different looks and different ideas. There was no obvious shadow in the original shot but I felt it added drama to the final look and I think the bright light high in the slot makes it believable.

If you are familiar with either program I'll go through the steps I used to complete the change. I wouldn't call it a tutorial, but a clue as to how it was done. In both programs I zoomed in to the figure and the Quick Selection tool did a fairly accurate job of selecting her. I used the Alt key with Quick Select to remove areas that were selected outside the figure and removed the areas between the legs and between the arms and the body. Once I had her accurately selected [Ctrl C] copied her to the clipboard and [Ctrl V] pasted her right back on top of herself but on a new layer which I could manipulate separately from the rest of the photo. I then, with the Move Tool, (top of the tool bar), clicked on the figure and dragged the copy of my girl to approximately her new location. In the layer pallet (screen right) I clicked the little eye at the left side of Layer 1 and the moved figure temporarily disappears (clicking the eye again will bring her back). Then still in the layer pallet I clicked on the background layer (it changed color) making it the active layer and I was ready to get rid of the immovable original figure.


Using the Spot Healing Brush (near the center of the toolbar and looks like a Band-Aid), I selected Content-Aware at the top of the screen. I adjusted my brush size by pressing the [ and ] keys to make the brush smaller and larger and selected a size about 1/2 as wide as the figure. I then painted over the figure by holding down the left mouse button and painting until the entire figure is covered with the dark tint. If you let go of the mouse button early you will get an incomplete removal and the best thing to do is click the Undo arrow at the top right of the screen or just press [Ctrl Z] on your keyboard and start over. Once she was painted over I let go and the content aware feature of the Photoshops filled the area in with an approximation of the background based on it's awareness of the surroundings. The Photoshop programs have come a long way in automating this removal (that's the Content-Aware part) but I was somewhat unhappy with the result and I used the Clone Stamp tool to touch up the area where the figure no longer existed.


Now it was time to deal with my copied figure. Clicking on that eye again made the copy visible and clicking again anywhere to the right of the eye selected the layer for working on that layer. Since I moved my figure to a position closer to me, she needed to be larger. I could have left her the same size and the canyon would have looked larger (an artistic decision). With that layer selected I pressed [Ctrl T] to activate Free Transform. A rectangle appeared around the figure with "handles" at each corner and the center of each side. Clicking and dragging any of these handles will change the size and shape of the figure. I wanted to change the size, but not the shape, of my girl so I held the shift key and clicked and dragged a corner handle away from the center until she was as large as I thought she should be. While the rectangle was still there I clicked inside it and, clicking and dragging, adjusted her position to a good location. I then used my keyboard arrow keys to more accurately finish the positioning and pressed [Enter] to complete the Transform. 


If you wanted to leave it without the shadow you're done. I want the shadow but this post is getting very long. I hope I've given enough detail to get you going. Next time I'll add the shadow.

HDR Photography

First let's answer the obvious question: what is HDR photography? HDR stands for High Dynamic Range. It has been a fact of life for photography from the beginning that many scenes we photograph have a range of brightness that will not fit on film. Now that the large majority of us are shooting with digital cameras we find that the brightness range of those scenes that will not fit on film will also not fit in a digital image.

Here are two photos taken at virtually the same instant. The one on the left was exposed to show detail in the brush and the wooden walkway on the left side. There is almost nothing visible in the sky and we miss the gorgeous colors of the sunset. However if we expose for those wonderful colors, as we did on the right, we loose all detail in the brush and trees on the land and half the photo is black.
Photographers, long ago, found a way to solve this problem; print the right image on the top of the paper and the left image on the bottom, but this only worked for darkroom folks. These darkroom artists created the first HDR images since they were able to create an image with detail that could not have been done with one exposure alone. For those of you familiar with darkroom methods; even dodging and burning will not recover detail that's not in the negative. Filter manufactures came to the rescue of photographers without darkrooms by creating graduated neutral density filters. The filter is half dark and half clear. Put it on your lens with the dark half on top and presto, the sky is correctly exposed and so is the land. Another however here, this only works when the dividing line between dark areas and bright areas is reasonably close to a straight line across the image.

With digital images we can combine the two just like the darkroom people did years ago. Now we electronically place the right image on top of the left image and erase the dark bottom to let the detailed land show through. This is not too difficult for even those without long experience in photo editing.

What becomes difficult is when the too light and the too dark areas are small irregular areas spread all over the image or when the brightness range is great enough that using three or four or five exposures is required to give you the results you want. This time it was software publishers riding to the rescue. You can now assemble many exposures into one with software you may already have and with programs you can download for free on the Internet. Photoshop and Photoshop Elements will do it. Photomatix is a very popular program that is just for HDR creating. On the Internet search for "free HDR software" and you'll get lots of hits. Check reviews before downloading to see if it's what you want.

The photo to the right was created by Photomatix from nine separate images including the two above (it was cropped slightly). HDR software allows you to create very realistic images, and as you see here, images that stretch reality to the breaking point. Some people love images done this way and others say things I wouldn't publish here. I'm in the group that like real and unreal. I'm lovin' what I get from Photomatix, but remember there are lots of free programs out there and even programs like Photomatix offer a free download to try.

On the even easier side, some newer model cameras have a built in HDR feature. You press the button it takes two shots, combines them, and presents you with the finished product.

Controlling Depth of Field

The photo left was taken with a 70-200mm f/2.8 lens. The lens was zoomed to 105mm and the aperture was set at f/22.  Notice that everything is in focus; the branch which was close to me, the bridge in the middle ground and even the brick school building across the road. All are reasonably sharp and recognizable. I was actually focused on the tree branch. Frequently landscape photos benefit from small apertures which will do just what you see in this photo, keep everything in focus.

The photo above was taken with the lens stopped down. If your not familiar with the term, it refers to a lens set at a small aperture. Lenses in common use have a range of apertures from f/1.4 to f/22. Not to confuse the issue, but the smaller openings have the larger numbers. All else being equal the larger the aperture available on a lens the more expensive it is. The photo on the right was taken with the aperture wide open at f/2.8. I was still focused on the branch and now the background has become much softer which causes the branch to become the obvious center of attention in the photo.




A more common use of the ability to throw the background out of focus is shown in the portrait at left. The photo of the boy was taken with a the same lens as the two in the park. It is a fast lens, again the term fast refers to the largest aperture available on the lens. If you look closely you can see that there is a chain link fence behind him but it is so far out of focus that you only notice the subject not the background.

Below another chain link fence virtually becomes the subject of this photo. This was taken with my cell phone. No cell phone that I'm aware of has anything close to a fast lens. As we saw above small apertures keep most of the scene in focus as in this case. Is it OK? That's for you to decide when you shoot the photo. It conveys a ball game behind a fence. It's not necessarily bad but the fence has a great effect on the image. Moving close and shooting through an opening would remove the fence if desired. Shooting with a fast lens would blur the fence and make it less important but may create a hazy look as in the photo, below left.
















Here the fence was so far out of focus that it is essentially invisible, however, it's ghost is there. The shot appears to have been taken through a cloud.
Why is the fence so blurred and the background soft but still fairly well defined? That is caused by the relative distances involved. The fence is about 5 feet from the camera and the young lady probably over 100 feet away. A drastic difference in focus terms. The deep red building is another 50 feet behind our all-star ball player. That means our subject is 20 times as far away as the fence but the red building is only 1.5 times as far as the girl.

Exposure Compensation

All DSLR cameras and many point and shoot style cameras are capable of exposure compensation, so what is it, when do you need it, and how do you do it. Well, I'll try to answer those questions here and maybe come up with an assignment you can try.

When you take a photo in any of the camera's automatic modes the cameras computer decides how bright your picture will be. The photo here was taken in a dark bar and the lights were my subject. The automatic shot looked nothing like this. My camera's computer did what it is supposed to do. It showed me a not very attractive old bar. The room was dark and the lights were interesting and it looked very different to me than it did to my camera, so using "Exposure Compensation" I underexposed the shot by 2 stops and got what you see here, a photo that looked like the room looked to me when I took the photo. Anytime the image you see on your camera's LCD looks brighter or darker than either "real life" or the image you had in your head, it's time to compensate.

How do you do it? The scary advice is "Look in you Camera Manual". If your manual has an index in the back look up "exposure compensation", or just look at your camera. You're looking for a button like the one shown on the Nikon (right) that shows a [+/-]. If you have such a button, hold it down and rotate the command dial. One direction will give you [+] numbers and the other will show [-] numbers. The numbers will likely either jump in half-stops or third-stops. The display will show [0.0] when you press the button and when the command dial is turned in the camera's plus direction it will change to [+0.3] and a photo taken now will be 1/3 of a stop brighter than before. Most cameras will allow up to [+2.0] and down to [-2.0] some may go to plus or minus three.

Now you have control over how bright your picture will be! Place your favorite subject against a bright sky and back up so that there is quite a bit of sky showing. Take a shot and look at it on your LCD. Your subject is probably a little dark so let's make it worse. Move your exposure control in a minus direction to [-2.0] and take another shot; see if you've created a silhouette. Not actually worse, just different. Now move the exposure in a positive direction; try [+1.0] and also [+2.0]. One of these will probably brighten your subject and make them look correctly exposed. If the change looks to heavy-handed remember you have those in between 1/2 or 1/3 stop positions.
I hope this gives you a tool and helps you get a photo you like better than the automatic one. Camera computers get better and better, but they will never know what you want so take control and keep shooting.

Using Your Flash at Speeds Faster than the Cameras “Sync” Speed

In normal flash mode the shutter needs to get all the way open then the electronic flash pops and exposes the image. After the flash is complete, which takes 1/1000 of a second or less, the rear curtain closes and the exposure is finished. The fastest or shortest exposure that is possible with your camera that allows the shutter to open fully before it begins to close is called the sync speed. Back in film days amateur cameras usually had a sync speed of 1/60 second. Today even moderately priced DSLRs sync speed is 1/200 or 1/250. Professional cameras maybe 1/500. Very few shutters will create a 1/000 of a second exposure that way. In order to allow photos at shutter speeds greater than the sync speed the rear curtain begins closing before the front curtain is completely open and therefore exposes a narrow slit which travels across the image. If the flash fires during this exposure only a narrow stripe of the image will be exposed. If your camera and your flash support it there is a way to use a flash at speeds faster than the sync speed. We make the flash stay on long enough to let the curtains complete their travel from one side to the other. With this system the flash will expose the film or sensor at any shutter setting during the time it takes the curtains to travel from one side to the other.

As an example using a Nikon D200 and a SB 600, from the camera’s menus choose “Custom Settings Menu”, indicated by the pencil, then choose “e Bracketing/Flash” and then “e1 Flash Sync Speed”. Choose 1/250 s (Auto FP) as in the image to the right.

You can do that as a trick mode with many high-end flashes and cameras. Nikon calls this the “Auto FP High Speed Sync” Canon refers to it as just “High Speed Sync”.