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Friday, February 24, 2012

Photography for Dummies, By Dummies: Episode 12

Ever had a question about photography you wanted to ask, but felt it was too stupid? Now you can feel stupid in private instead!

Disclaimer: The following graphics or photos found in this article are not my own, but acquired from easily available public forums of the internet and are used merely as examples of the concepts discussed in this article. I absolutely do not own the following images, nor do I claim to have personally shot the same. The following images have been copied and pasted directly from the internet with no editing or other forms of digital manipulation from me.

Here we go again! More photography myths. I love reading about photography myths for the simple reason that virtually all of us may have started with several misconceptions about phootgraphy. Certainly I was one of them. I was inspired to share this information by a close friend. He asked me about the price of cameras over the weekend as he wanted to purchase a DSLR. He asked about a lens that can 'do everything' so I suggested a simple 18-55mm with the Canon 60D - for price reasons, as well as the reasons below. He then decided he wanted the 18-200mm because he 'might want to zoom in on the subjects once in a while.'

Saying thus, it is fun to re-visit some of these concepts as we track our own progress up the photography food-chain.
1.         The Anti-Shake function in your camera does not mean that your pictures are guaranteed to be sharp.

Canon uses the term ‘Image Stabilizer’ (IS). Nikon has ‘Vibration Reduction’ (VR). Sony uses the term ‘Steadyshot’. Although manufacturers have a variety of colorful names for it, the system is the same – a vibration reducer. Many photographers deem this function a ‘must-have’ when using telephoto lenses. Even moreso if you are not using a tripod. At long focal lengths, a little vibration to the lens will produce multiple shake effects.

However, note the obvious – this feature does not reduce the movement of the object itself. This feature is used more to reduce the vibration coming from YOU. The most highly sophisticated anti-shake technology will not prevent your subject from constantly moving. You’re going to have to start developing better shooting technique then, as the anti-shake function is, at best, a nice thing to have, but certainly not a be-all, end-all camera function.

2.         A camera lens is better because it has a longer zoom.

That sounds just about right, doesn’t it? After all, the 18-55mm is way, way, cheaper than the 18-200mm. Wrong.

The fact is, a long zoom slows down the lens’ performance and can most definitely reduce the quality of your image. Over the past couple of years there are some pretty decent super-zooms in the market. Unfortunately, the best of the lot are not cheap. In fact, you could probably buy a small car with the price of some of the more luxury-class lens. Think RM 30,000.00. But for the ‘all-rounder’ lenses (super-wide to super-zoom), third party manufacturers like Tamron and Sigma have since come up with reasonably affordable lens. Arguably the quality of the images may not compare with the established brands, but what the hey.

If the above information does not make sense to you, you might want to read up on a few things you should know about your camera lens…

  1. There are many elements within a lens. The more the elements, the more intricate the trajectory path of light and this will likely in turn decrease the quality and sharpness of the lens. This is why a zoom lens has a lower sharpness than a fixed lens, because of the many elements within the zoom lens. Even if there is a zoom lens with a sharpness that can match a fixed lens, the price will undoubtedly be very expensive.

  1. Aberrations or distortions will always occur in wide lens (including the fisheye lens). That’s why wide lenses are not recommended for taking photographs of people’s faces because they will appear stretched and distorted. Also avoid using wide lenses for photographing straight lines.

  1. Sharpness differs in lenses. Sharpness will lessen when the lens is opened at its widest aperture or its narrowest aperture (lens diffraction effect). Zoom lenses also decrease in sharpness when positioned in its farthest zoom. For the best sharpness use wide to normal focal lengths, and use a mid-range aperture (also known as the sweet spot) of around f/5.6 to f/8. Below is test done on sharpeness by Ken Rockwell.

  1. The center part of the lens is always sharper than its borders. A good lens has a somewhat even sharpness between its center and its borders, while a bad lens’ sharpness severely decreases in its borders. This decrease in sharpness is called corner blurriness. But considering that the object of the image is mostly at the center of the composition, fortunately, people often times ignore the borders of the photograph.
  2. The maximum aperture opening of a zoom lens can change depending on the focal it is set on. To avoid complex lens designs, the zoom lens has its own peculiarities with different maximum apertures at different focal lengths. Pay attention to the inscription of the lens. For instance, the lens 35-105mm f/2.8-4.5 means that at a wide focal length of 35mm, its maximum aperture is f/2.8 and at its most telephoto zoom or 105mm its maximum aperture decreases to f/4.5.
  3. The super zoom lens has endured a lot of compromising. At the beginning, there is no lens that has an extreme focal length that can accommodate the needs of a 26mm wide to a 520mm telephoto zoom in one single lens. But due to demands in the market and the tight competition between brands, manufacturers are forced to create an all-in-one lens like the Olympus SP 570 with a 20x zoom. This type of lens has shot through the boundaries of theoretical optical physics, by sacrificing quality and sharpness, to meet the goal of being dubbed the all-in-one lens. A super zoom lens with a zoom range of 10x to 12x is fairly balanced between the telephoto capabilities and its output quality. While the 15x, 18x and 20x zoom lenses seem a bit forced and should be left for those highly ambitious in owning an ultra, ultra zoom lens.

To view other post in the Photography For Dummies Series, please click on the hyperlinks below

Episode 6: Image Stabilizers
Episode 8: Photography myths
Episode 9: How to keep your memory cards
Episode 10: Bad Habits of Photographers
Episode 11: Leading The Viewer

Thanks for viewing!

For those of you who like statistics:
Vital Stats for February: 4 posts 31 pics
Vital Stats So Far: 136 posts 5,401 pics

Disclaimer: The views published in the above photoblog are the author's and the author's alone. If readers are not agreeable with the above views, well, you can bugger-off. All rights are reserved for the the photos and/or articles itself. This article may be reproduced with permission for the author or private or public usage, or other forms of general mayhem. Any unauthorized usage of the images and/or article contained therein is expressly prohibited and violators will be prosecuted with the full force of Malaysian law applicable. Thank you for reading this disclaimer.

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