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Photography

I am pretty late to join the DSLR bandwagon. I just bought my first DSLR two months ago. In fact, it’s not even my camera, it’s the birthday present for my wife. When I first got it, I took some snapshot to make sure it works fine. Then camera hide itself behind the boxes when I moved and I just rediscover it this week. So I took some serious photos to explore the function of the new camera.

I am not new to photography, I had a have a film SLR camera lens in high school. I was the photographer with the best camera for the school year book, even better than the teacher adviser’s of the photo club. I was not that interest in photography back then. I got into photography because my best friends got a SLR and taking portrait is a cool excuse to ask the girls out. I didn’t touch the SLR since I got my very first digital camera in university. I always boast to my friends who get into DSLR in recent years that I was using SLR long before them. I know the use of shutter, aperture, ISO and filters and how they can affect the photo. However, it quite a shame that I never truly understand theory of photography.

This time when I pick up the DSLR again, I decide to have a complete understanding of photography. I bought a beginner photography book, read it from cover to cover, but still couldn’t get a very clear understanding. I still get the same fuzzy concept I know since my high school days. At last, I decide to learn it hard way. I log on the internet and read how DSLR works. I get to the root of the problem, understand the physics and optics of a SLR. Vola! Suddenly all the pieces fit together and I can link up all the photography knowledge I already know to form a big picture. The technical part of taking a perfect picture is simple. There is only two things you need to care about: exposure and color.

Exposure is controlled by three parameters, ISO, shutter speed and aperture. Shutter speed is the easier to understanding, it’s how long the shutter stays open. In film camera, ISO is the photo sensitivity of the film. In a digital camera, ISO becomes the signal to noise ratio amplifier. Aperture controls how much light arrive the sensor. Choose the right value of the three parameters allow the the senors collects the right amount of photons, so the image will not be too bright or too dark. The histogram is a handy tool to examine the exposure of your photo. The trade off between these three parameters is the artistic part and each one has its pro and con. The higher the ISO, the nosier the image. The slower the shutter speed, the more ghost in the image. The effect of aperture is the hardest to understand. Knowing how depth of field (DoF) works is some real hard physics. It took me almost two hours to completely grasp how the human eye’s field of confusion (FoC) determine the DoF of a given aperture. Color is not a pure optics effect, it is how the thermo-properties of light source affects the sensor. In a film camera, we use color filter correct the color, so a white object will show up being white in the image or we use the temperature of color to introduce mood to the image. In a digital camera, we can simply tweak the RGB algorithm in the sensor to correct the color of the image.

I found one advantage of DSLR over SLR. It is much easier to learn photography using a DSLR. The camera setting is saved with the photo and the image are ready to review instantly. I can take many pictures with different setting and compare the effects side by side. Most important, take photos is virtually free, so I can practice as much as I like. Unlike in the film camera days, buying film is expensive and you have to wait patiently for the film to develop. No wonder we have so many armature photography these days. DSLR really lower the learn curve to become a decent photographer.

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