Thanksgiving

So with the arrival of another thanksgiving, and the holiday season kicking into full gear, I wanted to share one of my favorite photos of all time. As a shutterbug, I have had to make a concerted effort not to inundate my blog readers with photos of my girls. They are, however, at the top of my list of favorite photo subjects, and as you can imagine they both are already used to the incessant clicking of my camera shutter. With that said, I hope you'll let me get by dropping some family photos on the blog every once in a while - with today being one of those days. 

This photo captures a moment in the life of my growing family, which is by far, the the thing I'm most thankful for this season. Reagan and McKinley are growing closer everyday, seeing their interactions (like the one below) fill my heart with joy.

I hope that you all have a wonderful Thanksgiving. Thanks for letting me share. God Bless. - Rob

Portrait Weekend

Thanks again to all of our wonderful customers who made our Holiday Portrait Special a big success this year. We are busy working on processing your photos, greeting cards, and other goodies so you'll have them in time for the holidays.

Those of you with public galleries should see your photos online sometime this week (or next week at the latest). Those with private galleries will be receiving login information by email when your photos are ready for proofing. As always, you can check out your pictures at http://galleries.townerjones.com

Here was one of my favorites from the weekend - just couldn't resist posting it...

Thanks again everybody, we look forward to serving you again soon! Have a happy and safe Thanksgiving!

Contest Reminder

Hi Everybody,

With the long weekend coming up I thought this might be a good time to remind you to shoot some photos and submit them for this month's photo contest... "Timeless"

You can get all the details here, hurry the deadline is this coming Sunday night!

All the best,

Rob

Back To Basics - Exposure: The Great Balancing Act - 5 of 5

Putting it All Together

So far, we've seen that shutter speed, aperture, and sensitivity all serve as tools to manage the amount of light we capture and modify how the camera interprets what it represents. We've seen that each tool comes with its own by-product as well. Adjusting shutter speed increases and decreases the amount of motion blur seen in our images. Adjusting aperture varies the depth of field, that is, the amount of our scene in front of and behind our subject that is in focus. And finally, adjusting sensitivity (a.k.a. ISO) shifts the scale of how light is recorded by the camera, while at the same time increasing and decreasing the amount of graininess (noise) seen in our images. With practice, the full range of each of these modifications will become a more and more natural part of your photographic decision making process - that is what I consider, The Great Balancing Act.

The Great Balancing Act

As I have echoed over and over again in this series, I don't believe there is a "proper" exposure. This is, in my opinion, in the eye of the photographer. However, I will conclude this series with a discussion of some example scenarios, where one might balance the tools at our disposal to achieve a certain result.

Scenario #1: The Baseball Game

It's a warm, summer afternoon and the home team is down by two runs in the bottom of the ninth. Two runners are on base, and the winning run is up to bat. You've got your telephoto lens on, filling your viewfinder with the batter - your goal is to stop the winning home run ball just as it leaves the bat of of the new hometown hero.

Quickly you consider that a baseball, just after the impact of a major league slugger, is traveling well over 100 MPH. The sun is providing all the light you could ever wish for, and you want as sharp a picture as you can take. What to do? We balance the tools at our disposal - With this much light, sensitivity can be set low, minimizing the noise in our shot, our aperture can be set in the mid-range, providing a medium depth of field - plenty enough to keep the batter in focus. Our primary tool of interest, hopefully clear by now is - shutter speed - we speed the shutter to it fastest rate... and <snap> we've stopped a baseball in mid air. You can still hear the crowd scream when you look at the photograph.

The key in this scenario and any photographic scenario is quickly determining what your goal is for the shot. Usually, by identifying a goal, you are pointed in the direction of which setting to optimize.

Scenario #2: The Wedding Ceremony

Before we continue down this path, let me give one small word of caution. Owning a nice SLR or dSLR does not make you a wedding photographer. Any wedding is the equivalent of the Super Bowl for any photographer, even a seasoned pro, and I want to make sure I'm not sending anyone out into the big game by giving the following example.

The bride and groom have exchanged vows and are standing there gazing at each other with all the joy and amazement that comes on such a special day. You've opened the aperture up all the way for a nice shallow depth of field, ready to really catch the moment. Your shutter speed in this light is just barely fast enough for you to be able to hold the camera still enough to take a shot without blur when - quite suddenly - the sun, coming through a few small windows in the church - goes behind a cloud. Now, with the moment quickly slipping away, you don't have enough light to make your exposure! The aperture is all the way open, no additional light to be had by changing that, and that shutter speed is already such that if you slow it down more (to let more light in) the image will be a blurry mess. What to do? Immediately, you bump up the sensitivity (ISO) and snap your image before the moment is gone - sure there's a little more noise in the image, but you were able to capture the shot. What you did was essentially made the camera more sensitive to the limited light you had, preserving your shutter speed in the process to protect from unwanted motion blur. Hopefully, at this point, you're really starting to see that knowing the ranges of each of the three variable options on the camera provides the confidence you need when you have perform the balancing act... without a net.

Scenario #3: A Child at Play

Like many photographers, some of my favorite subjects are kids at play. My three year old is a never ending source of energy, and one of the tricks to snapping a great shot of her is making sure the camera is being as flexible as possible. Let me explain. Remember the depth of field discussion from a couple days ago? It doesn't take much to realize trying to keep a kid within a 6-inch depth of field is no simple task. One of the combos I've used is bumping up the aperture to widen the depth of field, bumping up the shutter speed to stop her motion, and then raising the sensitivity to compensate for the decrease in light resulting from the other two choices. In this case, a single "most important" parameter isn't obvious - it's the combination of choices which adds flexibility to the shot, and increases the probability of catching a good pic.

 

Summary

Well, that pretty much wraps up my basic description of balancing the basic tools of the trade when in comes to exposure. As I've said before, the more you use your camera, the more comfortable you'll be at knowing what to adjust to balance the light for a perfect photograph. Just remember that aperture, shutter speed, and sensitivity each provide their own unique way of adjusting the amount of light captured by the camera, and that each comes with its own unique by-product. Future articles will address, in more exact terms the "how to" when it comes to camera hardware. For this article however, my hope was that you have found a basic understanding of the underlying mechanisms.

Please feel free to email me with questions and comments to: blog@townerjones.com

It has been a pleasure, hope you've enjoyed The Great Balancing Act.

Back To Basics - Exposure: The Great Balancing Act - 4 of 5

Sensitivity

Sensitivity, often referred to as ISO, is the third and final fundamental tool that the camera provides the photographer for manipulating the volume of light captured in a photograph. Unfortunately the reason I've saved it for last is the fact that, for most people, it is the hardest to grasp. However, the power it provides warrants taking the time to understand ISO inside and out.

If you've read the previous two articles about shutter speed and aperture, than you know what's coming, another analogy relating to water pipes and buckets. However, I'll admit up front that this one is going to require a little bit of a stretch to really understand what's going on, and it's certainly not as straight forward as the other two. Looking back, we said that shutter speed was analogous to opening a valve on a pipe and adjusting the amount of time it was left open to regulate how much water was collected in a bucket. Aperture was equivalent to fixing the amount of time the valve was open, but varying the diameter of the pipe to regulate the total amount of water collected. Of course, in our cameras, we're collecting light instead of water, but the analogies are fairly easy to understand. For sensitivity however, we'll leave the pipes and the valves alone and this time, vary the size of the buckets.

I'm going to talk solely about digital sensors now, because the analogy I'm going to use fits them slightly better in my opinion. Film cameras are very similar, but their process involves chemistry, a class in which I received a "mercy" C+ in college - you don't want me trying to explain anything related to chemistry to you.

The analogy: Imagine each pixel on the cameras's sensor as a tiny bucket, but instead of collecting the water, we use it for collecting light. For simplicity, we'll say that when the bucket is empty the camera records that pixel as being true black, and when the bucket is full, the camera records that pixel as being true white. All the amounts in between full and empty represent all of the other tones and colors the camera can capture. (I said, "for simplicity", because this description leaves out the filters and other engineering magic that make this possible; however, this simplified version gets the idea across, and is easier to wrap one's head around.) So now we have tiny buckets capturing the light - if we make the buckets smaller, they require less light to fill them up, the larger we make them the more light required to fill them up. What this means is that instead of varying the amount of light that comes into the camera (i.e. with shutter speed or aperture), we're varying the cameras definition of a full "light bucket."

You'll remember, the more light we collect, the "brighter" the photo. We now added a third tool to the toolbox which allows us to essentially slide around the amount of light required for the camera to register a certain brightness. That means, we can keep our aperture AND shutter speed constant, but still change the overall exposure of a photograph. If you think about the implications of that last statement, you'll realize that sensitivity seems like a magic addition to the balancing act, but as you might expect, it too comes at a price.

Trade-Off: Noise (Film Grain)

So by now, you've probably realized that if you make the "buckets" really small, you should be able to take pictures in near darkness, only requiring a very small amount of light to expose the picture. What you may not have considered, is that by doing so you've made the camera much more sensitive to a phenomenon known as noise. Noise shows up as a random colored grain throughout the image. As it gets more and more severe, it can actually begin to distort the image (as you'll see in the examples below.) Noise for digital cameras is the result of random electronic effects that exist in all electronic circuits. For film cameras, noise is known as film grain, and is the result of tiny crystalline structures that form during the development process. (That's as close as you get to chemistry from me folks) In both cases, it can either be looked at as a nuisance or in some cases, as an artistic addition to your photographs. As was the case with the other two trade-offs, I'm going to provide some examples below so you can see what noise looks like, and how it affects your photos.

The photo subjects for this illustration are two of the creepy, 3-foot-dolls my wife has down in her doll collection. I know it's not the case, but I swear it feels like these things move around on their own sometimes. Anyway... I've included the scene I shot below, as well as zooms (click on each for the large version) which show the noise added by going to higher ISOs. These shots were intentionally taken on my trusty old D200, as its high ISO noise performance, while decent, is far behind Nikon's newest cameras. Keep in mind, noise won't be apparent on the thumbnails, you really need to zoom in to see what's going on.

Full Scene

ISO: 100

ISO: 200

ISO: 400

ISO: 800

ISO: 1600

ISO: 3200, if you zoom in on this photo, you see that the noise is starting to dominate some of the edges, completely distorting some of the finer details

At this point, you've lasted through four days of my rambling, and hopefully have started to form some ideas about how the three fundamentals: aperture, shutter speed, and sensitivity, might interact with each other. We see that each has its advantages and disadvantages, and now we know what some examples of variations of each might look like in actual photographs.

With that in mind, make sure to join us tomorrow for the exciting conclusion of Exposure: The Great Balancing Act, cause it's time to start juggling...

Tomorrow - Conclusion