7 posts categorized "Back to Basics"

Monday, February 09, 2009

Back to Basics - Backup: Protecting Your Digital Photos

Back to Basics

It's late at night and a thunderstorm is rolling through your town. A lightning strike on the lamp post in the front yard sends a surge through the electrical grid, racing through the wiring in your house. The crash of thunder rocks the place and the lights go out. After a few minutes, the lights come back on. Everything seems to be ok, and as the storm passes, you begin to survey the damage. Most of the major appliances start up without a glitch... then you press the power button on your computer. The pit in your stomach gets larger and larger as a familiar boot-up process has given way to a lone blinking cursor. Your computer and everything on it has been fried by a hundred-million volts of nature's wrath.

So, this isn't just a "what could happen" example of why the subject matter in this article is critical. This happened to me while I was at home from college one summer evening at my parents house back in the late 90's. Yes, the computer was on a surge protector. What they don't tell you is that a direct lightning strike to the house's electrical system can cook even the best power strip, and that spike will find it's way right to the computer and the precious data on your hard drive.

Luckily, I learned my lesson early in life. As a photographer, I'm known for being extra paranoid when it comes to my backup strategy. Back in college, I lost a few term papers - today my family memories, and my clients' memories are in my care.

I'm going to give you an overview of what I do, step by step, when it comes to saving the digital photos I take. I'm not suggesting this strategy is great for everyone, but it works for me - and I'm confident that I won't be loosing photos anytime in near future. After I discuss my strategy, I'll mention a few brief details about the different options available for backing up photos that I use, and list their pros and cons. Long articles have been written about each and every backup method discussed here. You can consider this blog entry a Cliff's Notes version. 

Towner Jones Photography's Backup Procedure:

1) Photograph an event

Believe it or not, this is actually one of the most vulnerable moments for your digital pictures. For the majority of folks, it is at this stage that there only exists a single copy of the digital file. Make sure to use reliable memory for your camera, and take care to keep in clean, dry, and away from static electricity or magnets. We're blessed to have Nikon's D3 which incorporates dual memory cards to automatically backup each picture we take. It's actually one of the major selling points of the camera in my opinion.

2) Use Lightroom to import the pictures to the local hard drive, making sure to "Copy" the pictures, not "Move" the pictures to the drive. This ensures that the photos remain on the media card from the camera until more copies can be made. For those of you keeping track there's now two copies of my files in existence. The backup has begun.

3) A little magic happens during the previous step. My computer is set up with dual internal hard drives, in a configuration known as RAID 1 (more about that later) which essentially mirrors all information placed on one hard drive onto the other. So actually, when I copied the photos to computer from my memory card, it actually made additional copies. If one of the two hard drives in the computer ever fails, all of its data is mirrored verbatim on the other. Number of copies now in existence: 3

4) Using Microsoft's SyncToy (we've discussed that before, and we'll discuss it again briefly below) each night all the photos on the internal hard drives gets copied to an external hard drive. Number of copies now in existence: 4

5) The next day, after confirming that the external HD has gotten the photos from the shoot, I format the camera memory cards. Number of copies: 3 (that's the only time you'll see the number go down, unless I choose to delete a photo altogether)

6) I can now do my edits, organize the photos, whatever floats my boat. The nice thing about the mirrored hard drives is that all of these modifications are redundantly being duplicated in real-time. Each evening, the modifications made during the day get synchronized to the external drives. So most of the time, I'm always working 3 backups deep. That is until I take my obsession a couple steps further.

7) The first of each month, I open up my fire-proof computer media safe, and I pull out another external hard drive. This drive then gets synchronized with everything on the other external hard drive. We're now talking about 4 copies of each photo again, and we've now added the element of fire protection to the backup scheme.

8) Finally, as if that wasn't crazy enough, every six months or so, I'll burn a stack of DVDs containing a sampling of my favorite photos and take it to my parents house for "off-site" storage. One more copy for good measure, and the added element of off-site storage to round out the protection strategy.

It may sound crazy, but I sleep better at night knowing that it would take a major catastrophe (meteor impact, nuclear war, etc.) to wipe out all the copies of my pictures. Hopefully, that helps my clients rest a little easier as well.

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With my strategy spelled out in detail above, let's talk about the pros and cons of each of the major components, so that you can choose the ones that make the most sense for you.

Redundant Internal Hard Drives

Having multiple hard drives in your computer is probably the cheapest way to back up your data. (I've seen internal hard drives as cheap as 10-cents (US) a gigabyte.) It does, however, require the most amount of technical know how to set up, as it requires you to pop the lid off your computer and do the install. One the drive is in the machine you then have a couple options. 

Copy and Paste

You can simply add the additional hard drive as a separate storage location on the computer, and copy and paste your photos to the extra storage. This is manually intensive, and will require you keep track of what is copied where. Many new computer support another option, called RAID, which is a little more attractive.

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RAID (Mirroring)

RAID stands for "Redundant Array of Inexpensive Disks" and is a hardware and software option on many computers which allows multiple hard drives to work in some pretty neat ways. For all of the RAID options, check out Wikipedia, but the one we're most interested in here is mirroring. Mirroring sets up two hard drives on your machine to appear as one. Whatever is done with the files on the first drive is "mirrored" on the second drive. This makes it a very convenient backup strategy as your photos (and all of your manipulations of them) is backed up in real-time. Here's a couple important caveats. First, RAID only protects against hardware failures... not stupidity. If you "accidentally" delete a file on the primary drive, it will be deleted on the backup drive as well. For this reason, many people suggest RAID only be a part of your data protection solution and not your ONLY data protection solution. Second, it not the most convenient in the event of an actual hard drive failure. Sure all your data is there on the second drive, but you will need to crack the cover and do some hardware repairs in the guts of your computer when the time comes.

External Hard drives

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These, in my opinion, are the coolest things since sliced bread. (Yes, I'm a nerd) A few years back when these things started hitting the market, I had no idea how much I'd fall in love with them. An external hard drive is the exact same drive we talked about above, but instead of being in your computer, it comes in a handy-dandy little case, and sits next to your computer on your desk. The price of these guys continues to plummet, with capacity available at about 15-30 cents (US) per gigabyte. You can use them in the same way as internal drives (some even support RAID!!) but their USB, FireWire, or Ethernet connections to your computer make them mobile.

SyncToy

It's here I'll mention one of my favorite little PC applications made available (for free) by the folks at Microsoft. SyncToy, allows to to schedule and automate synchronizations of data between folders and drives on your PC. It is this application that makes my nightly backups of my internal drives to my external drives quick and easy. I've discussed this in detail in a couple other blog entries, so check them out here and here.

DVD (Archival grade)


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I mentioned that I burn a DVD here and there as part of my backup plan. The reason is simply time. Recordable DVD's has dropped in price and a comparable to hard drives from a cost per gigabyte perspective. However, now that an average wedding shoot nets 20+ gigs of photos, burning DVD backups just takes too long. For a few shots here and there, these are still EXCELLENT media for making copies of your pictures. Lab tests have shown them to last for many years when stored properly, with "Archival Grade" media purportedly expected to last up to 100 years. You'll notice I don't mention recordable CD's anywhere... it's because at 700MB there just too small for the large amounts of data generated by modern DSLRs. (I wish I had a time machine where I could go back a decade and tell myself that CD-Rs were going to be too small for anything... oh how technology amazes me!)

So that sums up the very basics of the technology involved in my backup process. Hopefully you found it informative enough for you to make some next steps in developing your own scheme. However, we're not quite done, before we finish, let's talk about physical storage.

Storage Locations

So you've taken all these great steps to protect your photos. You've got a zillion copies on a bunch of different media types... but then, God forbid, your house burns down. If you ask people when one thing they'd save from a house fire (after loved ones, of course) the majority of folks respond with "photos" - keep that in mind when developing your protection strategy.

Fireproof Safe

I get no kickbacks from these guys, but I love my Sentry fire-proof media safe. It's tiny, easy to access, and it stores my external hard-drive and DVDs like a champ. Check out Sentry's lineup, and pick out one that works for you.

Off-site

One last thing. Really, really bad stuff does sometime happen. When it comes to things like floods and tornados, even a good safe won't necessarily save your precious pictures. For these cases, off-site storage is a great solution. There's a bunch of companies out there that will be happy to charge you an arm and a leg to save your pictures to their servers, or send them your DVDs for safe-keeping in their vaults. Save your money and find friends and family out of town that will set up a "back-up photo exchange" - in the event of catastrophe, you'll be thankful you did.

Summary

Alright gang, that's my sermon on backups. I'll close with this last thought....

No matter what your strategy, it is CRITICAL that you backup your photos!

Computers are man-made objects and as such, they do not last forever. Back in the old film days, it took fire, wind or water to destroy your pictures. In today's digital world, they are MUCH MUCH more vulnerable. For that reason, it is imperative that you take measures to protect them.

I'll be happy to field as many questions as I can about your own backup scheme. Feel free to comment here on the blog (to benefit everybody) or email me at blog@townerjones.com

Until next time. All the best, Rob

Friday, November 21, 2008

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

Back to Basics

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.

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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.

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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.

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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.

Thursday, November 20, 2008

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

Back to Basics

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.

IStock_000006207912XSmall 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

Wednesday, November 19, 2008

Back To Basics - Exposure: The Great Balancing Act - 3 of 5

Back to Basics

Aperture

In the last article, we discussed shutter speed and learned that while lengthening the duration that shutter was open allowed more light into the camera, it also introduced motion blur into the photograph.

Today we'll talk about another fundamental control that the camera provides us - aperture. Hopefully the water faucet and bucket analogy from the shutter speed article made sense because you're going to read a variant of it right now...

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Imagine a water faucet filling a bucket. Once we turn the valve on, it makes sense that the amount of water filling the bucket would be determined by the diameter of the pipe. The larger the diameter of the pipe, the more water that flows when the faucet is open, and vice versa, the smaller the diameter of the pipe, the less water fills the bucket. For job security, photographers refer to the diameter of the "light pipe" that allows light to flow into the camera as "aperture".

Think of the implications of aperture for a second. We can now vary the amount of light coming into the camera by adjusting the diameter of the shutter opening, while keeping the shutter speed constant. We said yesterday that the end goal was capturing the right amount of light to get your desired photographic result - we've just added another tool to the toolbox for doing so. However, like the motion blur introduced by varying shutter speed, aperture comes with it's own by-product which requires consideration as well.

Trade-Off: Depth of Field

People who design lenses are very smart. I can assure you that I don't understand all the mathematics that govern optics and I won't bore you with the few equations I do understand. What you need to know is that aperture results in a phenomenon called "depth of field" and I'll try to explain it here. Depth of field relates to the distance in front of and behind the object you're focusing on that will be in focus. There are lots of depth of field calculators all over the internet if you'd like to calculate the exact numbers for a particular situation. We'll leave that for another discussion, but here's the general rule: the greater your aperture, the more shallow your depth of field. The smaller your aperture, the greater your depth of field. Memorize that right now.

Tangent: Another thing photographers like to do to protect their job security is refer to aperture values using the "f-scale." When using the f-scale, the smaller the number the greater your aperture diameter. That's the opposite of what you'd probably expect. Don't you just love photography!

To illustrate the depth of field, with the help of my three-year-old, I covered a table with 5 feet of miscellaneous stuff. I then lit the scene with overhead lights, set the camera up on a tripod, and started shooting away. The focal point selected by the camera (for all of the shots below) is on the "2FT" mark on the ruler. FYI: There is the a watch right behind the Nikon D90, and if you zoom in on it, you might think it's a Rolex... don't be too impressed... it's a knock-off - I don't have the funds for a real one!!)

Using a depth of field calculator, I'm also including the estimated depth of field. I've included larger zoom images than usual so you can really look at what is in focus and what isn't. It's worth clicking on each of these to see the subtle difference in focus.

Aperture: f/1.8, DOF: 0.32 feet

Aperture: f/2.0, DOF: 0.35 feet

Aperture: f/2.8, DOF: 0.5 feet

Aperture: f/4.0, DOF: 0.71 feet

Aperture: f/5.6, DOF: 1.01 feet

Aperture: f/8.0, DOF: 1.44 feet

Aperture: f/11, DOF: 2.08 feet

Aperture: f/16, DOF: 3.08 feet

Aperture: f/22, DOF: 4.77 feet - At this point, the entire scene is in focus.

I know I'm probably starting to sound like a parrot, but again let me say - like shutter speed, there's no right and wrong aperture. Depth of field is a powerful tool for composition of your photos. It can be used to isolate a subject from a distracting background, or it can be used to ensure that an almost infinite distance to the horizon all remains in focus. You as the photographer have to decide what you're going for in any particular photograph.

Now you've probably started realizing why I refer to exposure as a balancing act. You can capture the same amount of light in two different ways, a fixed diameter pipe which is left open for varying amounts of time (shutter speed), or varying diameters of pipe left open for a fixed amount of time (aperture). Each option carrying its own advantages and disadvantages. At this point, I'll ask for you to stop thinking about balancing the trades between adjusting aperture and shutter speed. Why you might ask? Cause that's what we'll discuss in part five of this series... and I don't want you spoiling anything.

Tomorrow, we'll discuss our third and final option, Sensitivity...

Tuesday, November 18, 2008

Back To Basics - Exposure: The Great Balancing Act - 2 of 5

Back to Basics

Shutter Speed

In the introduction, we talked about balancing shutter speed, aperture and sensitivity to collect the desired amount of light for the particular photograph you have in mind. However, the ability to balance these elements requires an understanding of the benefits and drawbacks of using each. In today's article we discuss shutter speed.

IStock_000004561027XSmall Back when I was wrapping my head around shutter speed the following analogy came to me, and I have since used it to explain shutter speed to a number of folks. Think of a water faucet and a bucket. If you open the valve on the faucet water starts filling the bucket. The longer the valve is open, the more water fills the bucket. Similar to the faucet and bucket, when we open the shutter on our camera, light starts being collected by the film or digital sensor. The longer we leave the shutter open, the more light we collect. The more light collected the more exposed (brighter) the photograph. We've said that the goal in terms of exposure is collecting the right amount of light to achieve your desired photographic result. Increasing or decreasing our camera's shutter speed provides one option for regulating the amount of light we collect for a given photo, but it doesn't come without trade-offs that must be considered.

Trade-Off: Capturing Motion

Based on the description above, one might think that exposure is as simple as shortening or lengthening the amount of time we leave the shutter open, but shutter speed has a characteristic directly tied to it - the ability to capture (or freeze) motion. In an ideal world (strike that, ...in a very, very boring world) all our photographic subjects would be completely still. In these cases, leaving the shutter open would simply collect more and more light reflected off the subject until you had your desired exposure. However, waves crash on the shore, fireworks explode in the sky, runners cross the finish line, and (the most elusive) toddlers smile for fractions of a second at the camera between bouncing off the walls. In all of these cases, leaving the shutter open not only allows more light into the camera, but it also captures all of the motion in the scene. Artistically, captured motion may be your desired result; however, understanding its direct correlation to shutter speed is fundamental to being able to intentionally balance our three basic tools (shutter speed, aperture, sensitivity).

In order to illustrate this concept of "captured motion" I set up the camera on a tripod, and shot a car passing through my field of view at nine different shutter speeds. The car is traveling at 55 MPH, that's about 80 feet per second, or just slightly slower than a three year old can move from one toy to another.

You can click on all of these pictures for a more detailed view... it would probably be worth your time to do so, but I'll leave that up to you.

Shutter Speed: 1/30 sec, I'm not going inundate you with a great deal of math, but during this 1/30 of a second, the car has moved almost 3 feet. The resulting motion is captured in the elongated streak of the car.

Shutter Speed: 1/60 sec

Shutter Speed: 1/125 sec

Shutter Speed: 1/250 sec

Shutter Speed: 1/500 sec, In my opinion, this is the first photograph in which the larger features of the car have an acceptable level of sharpness for a basic snapshot. The reason: In 1/500 of a second, the car has only moved about 2 inches during the photograph. Blur still certainly exists, but finer details like the spokes on the tires start to appear.

Shutter Speed: 1/1000 sec

Shutter Speed: 1/2000 sec

Shutter Speed: 1/4000 sec

Shutter Speed: 1/8000 sec, Now we're tack sharp. Zooming in reveals that even the spokes on the wheels are nearly motionless. The math explains why, in 1/8000 of a second, the car has moved less than 1/8 of an inch. In terms of general photography, we've essentially frozen the car's motion completely.

As I mentioned yesterday, there is no "right" and "wrong" for these photographs. What is important is understanding that the trade with letting more light into the camera by using shutter speed is that the resulting motion during the open shutter is captured in your photograph.

Tangent: There is additional motion introduced into a scene as well. This motion isn't introduced by the subject, it's introduced by the photographer. Shaky hands, breathing, your heart beat, all of these move the camera and in turn introduce motion. I personally have a hard time hand holding a shot at 1/15 second. (My wife, Rose, on the other hand, likes to show off and turns out stunningly sharp photos at 1/15 sec all the time just to rub it in... but I digress) This "camera shake" as it is often called, needs to be considered as well as part of the shutter speed/motion capture balance.

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Firework bursts on the Fourth of July, a waterfall, an ocean wave, a shooting star across the night sky, the checkered flag at the Indy 500... These are just a few of the many different situations that require different shutter speeds. Experimenting with your camera is always the best way to learn the correlation between what shutter speed is necessary and what result you desire.

Alright, let that stew until tomorrow when we dive into understanding aperture.

Tomorrow: Aperture