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DSLR Guide News, July 2006 - What Are ALL SLRs Missing?
August 28, 2006
The One Missing Feature on all Digital SLRs
Table of ContentsIntro - The Missing Feature
SLR Q and A - What's Dynamic Range?
Photo Recipe - Poor Man's HDR
The Gear - What's Canon up to?
Recent Updates - New Articles at the Guide
SLR E-course - Back-to-school Special!
Learn More - Digital SLR Resources
IntroductionI was hoping to stir up some intrigue with the title to this month's newsletter. Did it work?
I'm devoting this entire issue of the Digital SLR Guide's newsletter to a discussion of the one feature that is missing from all digital SLR cameras today. It's called HDR, which stands for High Dynamic Range.
When I purchased my first digital SLR back in 2002, it was a pretty basic camera. Like a film SLR it was fast, responsive, and I could change the lenses as much as I wanted. Beyond this, it didn't have any additional bells and whistles.
Take a look at cameras today: built-in anti-shake, self-cleaning sensors, on-demand viewfinder grid lines, live view LCD screens...the list of "extras" is extensive.
In an effort to compete with each other and be unique, the camera companies are loading their cameras with features designed to help photographers take better pictures. Many features correct common mistakes.
Advanced autofocus systems ensure that your primary subject is sharp, and proprietary metering systems evaluate all of the light hitting the sensor, make some calculations about shadow and light, and figure out how to correctly expose the photo.
All of this is intended to make you think less about what your camera is doing so that you can focus on taking pictures.
What's surprising then is that all of this advanced digital technology still has not found a way to get around the most common limitation of film cameras: dynamic range.
Digital SLR Q&AQuestion: What's Dynamic Range?
Answer: Instead of jumping right into an answer, let me ask you this: have you ever taken a photograph where the scene looked fantastic to your eyes but the photo you took looked just plain terrible?
I'm pretty confident that your answer is yes - it happens to everyone all the time.
Let's dig into one reason why the photo might not live up to your expectations: your eyes have immense dynamic range. This means that when you are standing inside a shaded valley with a beautiful blue sky overhead, you can see all the details in the trees and you can also tell the sky is blue.
Here's the gotcha: your camera can't.
When faced with beautiful scenery like this, your digital SLR will do one of two things: it will take a photo where there is plenty of detail in the shadows and turn that nice blue sky into pure white, or it will capture the blue sky and turn everything in the valley to pure black.
Here's an example that I shot in the Yosemite valley. The sky looks good (it's blue, not pure white) and the reflection is OK, but the trees in the middle are almost completely black - there is no detail or color there at all.
But why does this happen? Is it the photographer's mistake or some camera setting that can be tweaked?
It happens because every digital SLR has a limited dynamic range. This is not unique to digital - all film cameras also have limited dynamic range (although in this case it's the film that is limited not the camera).
Here's what you have to be aware of: it is IMPOSSIBLE for any digital SLR to capture the same range from shadow to light that your eyes can see.
This is why many landscape photographers don't take pictures in the middle of the day. The contrast produced by direct sunlight is too great, and it's inevitable for parts of the photo to appear either as white or black.
This is also why direct sunlight is not ideal for portrait work. Let's say that your subject is turned at 90 degrees to the sunlight. If the camera exposes for the light side of the face, the dark side will be pure black - one eye will disappear. If the camera exposes for the shadows (so there is detail) the other half of your subject's face will be pure white, losing all color.
So what's a photographer to do?
First, you have to recognize when the contrast is too severe for the camera to capture all the details from dark to light. This skill develops with time and practice. Eventually, you will be able to recognize when the light is even enough for your camera to capture the entire scene correctly.
Second, you have to make choices. There will be times when you want to take a photo, but the light is just not as even as you'd like. In these cases, decide which part of the photo you're willing to give up: the highlights or the shadows. If the shadows are more important, set your camera to capture the detail there knowing that highlights will be pure white. If you really want detail in the highlights, expose for those and let the shadows turn to black.
Or, take both photos and blend them together.
Hey, that leads nicely into our next section.
Photo RecipeA photo recipe is a simple way of breaking down a photography technique.
Please send in your ideas for photo recipes! I'll include your requests in a future issue of the newsletter.
June Photo Recipe - A Poor Man's HDR
One way is to purchase software that creates HDR (High Dynamic Range) images. There are two problems with this approach: first, the software will set you back a fair amount of money and there is a learning curve associated with creating HDR photos. It's not exactly point-and-click.
I am going to introduce you to the alternative: a way to create HDR images without buying a lot of software or spending a huge amount of time.
STEP 1 - Set up the camera
Every photo that you take will come in threes rather than just one at a time. Once you activate auto-exposure bracketing, you're also going to have to adjust the amount of over and under-exposure. It's up to you, but I typically set the camera to over and under-expose by 2 stops. This gives me a lot of range to work with.
STEP 2 - Take the photo
One tip: press the shutter button halfway down with autofocus activated so that your camera can focus. Then flip the switch (on either the camera or the lens) to activate manual exposure. This will ensure that the focus point is the same in all three shots (otherwise your autofocus will want to re-focus for every photo you take).
STEP 3 - Edit the results
Since there was a lot of contrast in the scene, you should have one photo where the highlights have no detail (pure white) and another where the shadows have no detail (pure black).
Copy the image where the highlights are too bright and paste it on top of the one where the shadows are too dark. This is why you need an image editor that will let you layer photos - I use Adobe Elements (version 3 - Adobe seems to have made a bad mistake with their upgrade to version 4 which I don't recommend to anyone) which is a great tool for simple photo editing and enhancement.
Select the eraser tool and if the option is available, adjust the opacity of the eraser so that it doesn't erase 100% of the image. A setting of 50% is usually a good starting point.
Carefully erase the too-bright portions of the top image to expose the darker image underneath. Be careful that you are only erasing the highlights and leaving plenty of detail in the shadows.
When you're done blending the two images together, flatten them (creating one layer) and save the photo.
Voila! You've just created an HDR image (of sorts) where the dyamic range in your finished product is much more than your camera's sensor could capture all at once.
It may be dawning on you why the tripod is an essential element to creating HDR photos: if the camera moves in between the two shots you are trying to layer together, the effect won't work - the viewer will be able to tell that the photos don't line up. When the camera is locked on a tripod, there is no chance of it moving during your multiple exposures.
Digital SLR GearWith the release of the Nikon D80 (which you can read more about with my Nikon D80 Preview guide) and the competition heating up between the various camera manufacturers, this brings us to a very interesting question.
Where the heck is Canon?
Not a word has been heard from the most popular maker of digital SLR cameras, and they haven't released anything new since the 30D early this year (which was not hugely different from the 20D released in 2004).
The last true consumer digital SLR released by Canon was the EOS Rebel XT, and that made its appearance in March 2005.
It's somwhat unnatural for a company dealing in consumer electronics to be dead quiet for an entire year, so I suspect that one of two things is going on.
It seems that despite their market dominance, Canon is eventually going to have to come around and adopt some of the innovative features pioneered by companies like Sony (who acquired their technology from Konica Minolta) or Olympus.
For example, all Olympus cameras have a self-cleaning sensor that eliminates particles of dust. Digital SLR sensor dust is not a huge problem, but it can affect the quality of your photos. The self-cleaning sensor - while not essential - is a feature that is nice to have.
The Sony cameras have built-in anti-shake which reduces hand-held camera vibration and leads to clearer shots. While you can also get anti-shake with a Canon camera (they call it IS for Image Stabilization) you have to purchase a special IS lens that is significantly more expensive than a lens without IS.
Only time will tell what the successor to the Rebel XT will include. For now, Canon fans will have to resort to cameras that are perfectly functional but are beginning to get upstaged by the advancements in digital SLR technology.
P.S. It figures. Right after I completed this article, Canon announced the release of their next digital SLR camera: the Canon EOS Rebel xTi. With 10 megapixels and a self-cleaning sensor, it seems like Canon is not going to lay back and let the other camera manufacturers run rampant. I will be posting more information about the new Rebel xTi soon.
Recent Updates to The GuideThe updates this month have not been as extensive, since I've been focusing on my Nikon D70s guide (and I managed to catch a cold for an entire week...in the Summer...imagine that!). Expect the D70s guide to be posted by the end of this month (shortly after you get this newsletter).
For all the latest updates to the Guide, keep an eye on the Digital SLR Weblog.
SLR Guide E-CourseDon't miss great photo opportunties!
Learn how to adjust your camera settings to get the most out of every shot you take with 5 photography lessons from the Digital SLR Guide.
It's a lot easier to leverage all the features of your digital SLR than you might think.
And beginning in September, it will also be a lot cheaper.
The 5 lessons are usually available for a mere $14.95, but for the first two weeks of September that price will drop to $9.95. If you've been wanting to learn more about your digital SLR, consider this your back-to-school special.
Digital SLR Learning ResourcesEach month I will present a new photography book or online resource that will take your photos to the next level, and help you continue to learn about photography (if that's your desire).
August Resource: Family Portrait Photography
I've introduced you to several different photography resources over the past months, but I've been neglecting one key group: portrait photographers.
To address this problem, this month's photo resource is for anyone who enjoys portraits - specifically, family portraits.
The most common problem when it comes to photographing groups of people is actually one that you have control over: how they are arranged and posed. It's pretty amazing how slight adjustments to the tilt of a head or the position of a hand can make or break a family group portrait.
While The Best of Family Portrait Photography is geared toward the semi-professional photographer, there is a lot that an amateur can learn here.
The posing sections are comprehensive, and show you not only how to get individuals looking good, but also how to build a group of three or more people in a way that looks elegant and natural.
Here's the part I like the most: an entire chapter is devoted to taking portraits of children, who are notoriously difficult to photograph. They can't be posed and almost never want to look at the camera or cooperate.
The chapter on child portraits gives a lot of good suggestions about how to improve the photos you take of both babies and children, including how to position them, keep them interested (the hard part) and what sort of lighting is the most flattering.
Another nice aspect of this book is that it is chock-full of photo examples of each technique in action. Having said that, keep the following in mind: the photo samples are from some of the best portrait photographers in the business.
The rest of us could work with a single child for hours and still not get some of the images that are shown in the book.
But at least they give you goals to shoot for - concrete ideas and examples that you can try to emulate on your own. I find that trying to copy the look and feel of a professional image is a great way of discovering and enhancing your own photography style.
Friends and family members know that I take a lot of photos, and so I am usually the unofficial photographer for family gatherings and events. Using techniques that are outlined in this book, I have seen a significant improvement in both the individual and group photos that I take.
In ConclusionThat wraps up the newsletter for August.
I'd like to extend a warm welcome to all of the new subscribers - I hope that you continue to find these issues of Digital SLR Guide news useful and informative. As always, feel free to ask a question or provide your feedback.
Speaking of which...next month I will be requesting some help from you, the readers. November will mark the one-year anniversary of this newsletter, and in order to prepare for that I will be asking for your feedback next month.
I'm putting together a short questionnaire that will provide me with more insight to the topics that interest you the most. The more feedback I get, the more I will be able to tailor this newsletter to the needs of the audience.
This seems like a better solution that just letting me pontificate about SLR camera technology each month.
Look for more information about the questionnaire in next month's newsletter.
Until then, thanks for reading and happy picture taking!
--Chris Roberts, Your Digital SLR Guide
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