Posts filed under aperture

Canon EOS 350D comments: Shutter speed

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Imagine a guy with bare feet walking as quietly as possible through the underbrush of some bushy area, stealthily walking over to a fallen dead tree and then climbing up that tree to wait.

I've seen the tree before. It's a very large tree that was apparently pushed so hard by the wind that its trunk broke several feet off the ground allowing the wind to push the whole tree to the ground. It's been dead for quite some time now and it's a boon for me because it's produced an empty space in the middle of the bush, and a platform from which I can sit and watch the birds fly around.

The tree is now horizontal so it's easy to walk up but I still need to be careful climbing it because you never know when the white ants will have eaten enough of the tree; nature's recycling system; to weaken it, eventually allowing it to break under my weight. So far though, the tree doesn't budge when I walk on it so it's very safe for the time being.

I sat and stood on the tree trunk, some twelve feet off the ground, just watching and waiting for two or three hours, relaxing in the warm winter sun and admiring the blue skies that have become so rare now here in Hong Kong. I knew the birds frequented this place so it was just a matter of waiting with camera in hand. I was sure to get something.

Eventually, the birds did come and I was able to get a few reasonable photographs. I say reasonable because I'm finding it hard to get good photographs with my Canon EOS 350D camera. Under normal circumstances photographing normal things, the camera's definitely ok, but when I'm trying to get close to objects or when the available light begins to drop even just a little, the camera becomes a hindrance and I'm left questioning my age, eyes and skill.

The problem is light. Unless the sunlight is in full force, I need to set the camera to ASA200 for most of my shots to get a reasonable shutter speed. Even then, I find myself shooting many of my shots at just 1/30th of a second. For many shots, that's ok but for moving objects, it's too slow. I think the camera suffers from two problems: the sensor is small at only 22mm instead of the traditional full frame 35mm, and the sensors are not as sensitive as similar rated film; i.e., EOS 350D' ASA200 == film ASA100. One day soon, I'm going to try taking similar shots with both of my cameras and see if the EOS 5 does in fact make better shots easier to get.

At ASA200 on the digital camera, the photographs are not fine. This becomes more obvious when you blow up the pictures to full size and the details are not sharp. In addition, darker parts of the photographs are grainy and weak.

When taking pictures of birds, the problems become accentuated. Because I'm using the equivalent of a 224-640mm lens (70-200, x2 for the extender, x1.6 for the 22mm sensor), camera shake becomes a real problem. Even minute movements will cause the picture to blur. Add to that the speed of the birds' movements and it becomes evident that slower apperture speeds are out of the question. My testing so far indicates that I need at least 1/125s to avoid camera shake, and at least 1/160s to avoid blurring due to a combination of camera shake and bird movement.

At ASA200, this is only just possible for the lighting available to me at present but there's another problem. More often than not, the only way to get 1/160s shutter speeds is to use the maximum aperture value on my extended zoom lens; f5.6. For close-ups at 640mm with an aperture of f5.6, the depth of field can be extremely short, as short as just a few millimetres, so getting perfectly focused photographs is very difficult. I also prefer to get more in focus than just the bird's eyes so it's a blessing when the light allows aperture values of 10 or more.

Until yesterday, I was using Aperture-Priority programming to shoot bird photographs, usually setting the aperture to f5.6 but also shifting to f6.3 or f7.1 or even f8.0 when lighting allowed. Yesterday, it finally occurred me; remember that I'm an amateur photographer so please don't laugh; to use Shutter-Priority programming. With the ASA to 200, I set the shutter speed to 1/160s and let the camera do the rest. This way, I would automatically get greater depths of field when possible without any effort on my part. If I was shooting areas which were too dark for 1/160s at f5.6, it wouldn't matter because the result would be a darker picture similar to what was being photographed.

I am pretty happy with the photographs I took yesterday but after reviewing them, I have decided that 1/200s is probably a better choice than 1/160s. I'm also determined to try using the EOS 5 film camera soon to see if I can get better colour and grain than when using the 350D digital camera.

I have much more to say about the EOS 350D camera but I'll leave it for another post.