March 22, 2009

Accurate Flower Colors

Daisy Blue

Spring is officially here, by the calendar if not by the temperature here in Montana. And that means wildflowers will soon be poking their heads up through the last bits of snow and mud. When you go out to photograph them with your digital camera, be aware that the camera may not always record the colors you see with your eyes. The way your digital camera captures flower colors is affected by the shooting mode you use.

I purchased a bouquet of flowers to practice close-up photography indoors. In the bouquet was a chrysanthemum of a lovely pale pink. I photographed it using three different settings on the camera. Each of them recorded a different color!

With the camera set on AUTO exposure, I got a flower that was definitely in the purple category. It looks nothing like the real thing!

Automatic Mode

Then I tried the Scene setting called Foliage. This brightens and intensifies colors and has worked very well for fall leaves. I thought it might do well with the flower. This version was closer to the flower's real color, pink, but a little on the dark side.

Foliage Scene Mode

For the third version, I switched the camera to Program mode. This is similar to automatic, except it allows you to customize several camera settings. I changed the exposure compensation to +2/3 to make the image a little lighter. And I changed the white balance to daylight instead of auto. These two adjustments gave me a photo that is closest to what the flower looks like to my eyes.

Program Mode with
+2/3 Exposure Compensation &
Daylight White Balance


So when you take flower photographs, experiment with different camera settings, including exposure compensation and white balance. Changing these can make a world of difference in the colors you record.

Shooting Blind

Last week I went out for my daily walk and took my pocket digital camera along. It was a mild (for Montana) late winter day under a cloudy sky with a bit of a breeze. Since I was teaching a class on close-up photography at the time, I had my eye out for subjects suitable for this technique.

That's when I spied the old wooden fence posts with rusty wires and clips attached. I set my camera to macro focusing (the little flower symbol) and started to frame pictures using the LCD screen on the back so I could compose accurately.


Unfortunately, I could barely see what I was pointing the camera at! Even with the overcast sky and relatively dim lighting, I was getting a dark image on the screen and a nearly mirror reflection of myself in the monitor. Needless to say, this really hampered my efforts to get the photos I wanted. I would take a couple shots, then review them in playback mode. But usually I couldn't see these any better.

Even though my camera has a window (optical) viewfinder, like point & shoot film cameras, it is not accurate when framing close-ups. Although I tried this once or twice, I ended up deleting the pictures because my subject wasn't framed properly.

For the first time, I actually wished for an Electronic ViewFinder (EVF) on my camera. This is a miniature LCD screen enclosed in an eye-piece like a traditional SLR camera. With it you can accurately compose your close-up images because you are seeing what the lens sees. And it allows you to easily see your composition in bright lighting conditions, even on cloudy days.

In the past electronic viewfinders presented a coarse image that often could not keep up with camera movements, causing the viewfinder image to "jump" to the new angle of view. But the EVFs I've seen on more recent cameras seem to have overcome these limitations to a large extent.

So if you do a lot of close-ups with your compact digital camera and you try to do this in bright lighting conditions outside, you may want to look for a new camera with an electronic viewfinder. Then you won't have to shoot blind and hope for the best.

March 9, 2009

Instant Black & White Photos

The rise of digital cameras' popularity has coincided with a renewed interest in black & white pictures. While most professional photographers maintain that the best digital black & white images come from converting full color photos using computer software, many amateurs are more interested in black & white without the time in front of a screen.

There are a couple ways to accomplish this. The simplest is to have a photo lab print your color original as a black & white image. But nearly all digital cameras have a setting to create black & white photos directly in the camera. Check your camera's manual for a "monochrome" or "bw" setting.

If you have a compact digital camera, changing to black & white mode causes your camera to display a black & white version of the scene you are framing right on the LCD monitor. This is a great advantage to learning to "see" black & white images. If you have an SLR, you have to take the photo first and then play it back to compare the monochrome version to the original color subject.

Besides black & white, some digital cameras have a sepia ("see-pee-ah") setting which produces a brown & white photo reminiscent of historical pictures. This is effective for photographing old buildings and people in historical costumes, such as at a Civil War reenactment. Many digital SLRs have other color choices (such as blue, green and purple); look for an entry in the camera menus called "tones" or "tints".

So what makes a photograph interesting in black & white? Light and shadow become very important to your pictures without color. Look for light coming from the side or behind the subject for dramatic results. Watch for interesting shadows created by the light.

Texture also becomes more prominent in monochrome photos. Texture is a visual sense of how it would feel to touch the subject in the picture. Lighting coming from one side at a low angle produces the most pronounced effect.

Seek out things to photograph that are already black and white in color. Also search for subjects that are one color throughout but have interesting differences in lighting or texture.

See the fun you can have with the black & white setting in your camera! And all without paying extra for special prints or spending time in front of the computer.

March 2, 2009

Keeping Your Camera's Sensor Clean


Arctic Butterfly Sensor Brush (top) & Hurricane Blower

If you have a digital camera with interchangeable lenses (called an "SLR" for Single Lens Reflex), such as a Canon Rebel or Nikon D40, you may have noticed black spots or specks in your pictures when you looked at them large on a computer screen or even after you had the images printed. These black spots are dust sitting on the protective filter covering the sensor in your camera. When you change lenses (and even if you don't), it is possible for dust to settle on the sensor and stay there for every succeeding frame. While you can retouch these spots with your favorite photo editing program, it is time consuming. Here are some tips to prevent unwanted dust and to deal with it if some gets on your sensor.

Prevention is better than a cure in all cases. First, if you are shooting in a location with lots of dust, do NOT change lenses! At the wild west rodeo or the breezy desert or ocean beach, keep the lens on the camera. If the sensor isn't exposed to dust in the first place, you won't have to worry about it. If you must change lenses, return to your car and change the lenses inside the protected space.

Second, always turn off the camera before changing lenses. When the camera is powered up, the sensor creates a small static electric charge which can attract dust, pollen and other floating debris. If you turn off the power, the static charge dissipates and lessens the likelihood of getting more dust on the sensor.

Third, when you do change lenses, do so as quickly as possible to avoid exposing the sensor to the air for any length of time. Here's a routine to practice: A) Turn off the camera. B) Select the new lens you want to mount on the camera and remove its rear lens cap. C) Remove the lens on the camera. D) Attach the new lens. If the camera is on a tripod, this is easy to accomplish. If you are handholding the camera, make sure you have a safe place to lay the first lens when you attach the second lens.

Check your sensor for dust before trying to clean it. The easiest way is to photograph a plain, white or light-colored surface, such as a clear blue sky or a blank wall.
  1. Set the camera to Aperture Priority exposure mode (A or Av on your exposure dial).
  2. Select the largest f-number available, usually 16 or 22. This will ensure that any dust spots are sharp and dark enough to be visible.
  3. Turn off the Autofocus setting; it won't be able to focus on a blank sky or wall without details.
  4. Photograph the sky or wall.
  5. Download the picture to your computer.
  6. Open the photo in any picture viewing software
  7. Display the picture at 100% or Actual Pixels size.
  8. Scroll carefully through the whole photo, checking for spots.
  9. If you don't see any, no need to clean the sensor! If you do see some spots, you can proceed to the cleaning stage.
Even if you have a camera model with built-in sensor cleaning, you may still wind up with dust specks on your sensor. There are several levels of cleaning you can take, depending on your individual comfort level and how dirty your sensor is. The safest method is to take (or ship) your camera to an authorized dealer/repair center to have them clean the sensor. This honors the camera warranty and frees you from any risk of damage to your camera, though there will be a charge and some time without your camera. You may want to check local camera shops in your area to see if they offer a sensor cleaning service.

If you are willing to try cleaning your sensor yourself, here are some easy steps. NOTE: Perform these steps at your own risk. If you damage the camera sensor, you may void the warranty.

The first method is to use a large bulb blower to blow dust off the camera sensor. You can purchase a Rocket Blower or Hurricane Blower at most camera stores, or simply find a large bulb blower at your local pharmacy.
  1. Be sure you have a fully charged battery in the camera.
  2. If your camera has a sensor cleaning menu choice, select this. Otherwise, turn on the mirror lock-up function. (Consult your camera manual for instructions.)
    Both of these menu choices flip the mirror up out of the way so you can see the camera sensor.
  3. Remove the camera lens.
  4. Hold the camera securely with the lens opening pointing down so the loose dust can fall out of the camera.
  5. Carefully insert just the tip of the blower just inside the lens mount. DO NOT TOUCH THE SENSOR with the tip of the blower.
  6. Give two or three firm blasts of air to dislodge any dust.
  7. Turn off the camera to cancel the sensor cleaning/mirror lock-up.
  8. Check your results on the computer by photographing the plain sky or wall again.
DO NOT USE CANNED/COMPRESSED AIR to blow dust off your sensor! It is too strong a blast and could damage the insides of your camera. In addition, the propellent may "spit" on to the sensor, making the problem even worse.


If the blower method does not completely clean your sensor, you may advance to wiping off the sensor with a dry or wet method. I use a special sensor cleaning brush from Visible Dust called the Arctic Butterfly to clean the sensor in my camera. This battery-powered brush is small, light and contains no liquids so it's safe to carry on airplanes. The battery causes the brush to spin, creating a static charge which attracts dust. Then you turn off the spin and gently wipe the brush across the surface of the sensor. Remove the brush from inside the camera and spin again to remove the dust. You can see specific instructions and a video on this method at the Visible Dust web site.

If your sensor has stubborn spots stuck to its surface, you may need to use a special solvent and cleaning wand to clean up the mess. VisibleDust sells these tools also, but I have not had to use them.

There is a web site dedicated to discussing and demonstrating a variety of sensor cleaning methods. For in-depth information on cleaning your sensor, visit www.cleaningdigitalcameras.com.

With a little care and forethought, you should be able to keep your digital camera's sensor clean for pristine photos.