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| The Zooming Buttons: 950 |
The on-camera zoom lens covers focal length from 38mm to 115mm (35mm equivalent). Near the upper-right corner of the back panel there are two buttons marked with W and T (see the figure below) for zooming out (wide angle) and zooming in (telephoto), respectively.
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| The Zooming Buttons: 950 |
You can see the image through the viewfinder or on the LCD monitor. When you change focal length, you will notice two important effects: angle of view and magnification. When the focal length becomes smaller (resp., larger), the coverage in the photograph is larger (resp., smaller). Section Focal Length below will discuss these effects.
The on-camera zoom lens covers from 38mm to 115mm. That is, it covers normal (or standard) to moderate telephoto. With the 0.66x wide angle converter the on-camera zoom lens is converted to roughly 24mm to 72mm. With the 2x tele converter the on-camera zoom lens is converted to roughly 75mm to 230mm. Therefore, the on-camera zoom lens plus the two converters cover 24mm (ultra wide angle) to 230mm (telephoto). This coverage should be sufficient for most photo taking situations.
Since the on-camera zoom lens does not cover the wide angle range (i.e., 24mm to 35mm), the wide angle converter is used. Please refer to the wide angle converter page for the details. The following three photographs illustrate the effect and coverage at three focal lengths. Note that these are approximates rather than exact values.
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| 24mm | 28mm | 35mm |
| Click on the picture to see a full size one | ||
The on-camera zoom lens covers 38mm to 115mm. The following three photographs illustrate the effect and coverage at three focal lengths. Again, these are approximates rather than exact values.
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| 50mm | 75mm | 100mm |
| Click on the picture to see a full size one | ||
Finally, to reach a focal length greater than 115mm, the tele converter must be used. Please refer to the tele converter for the details. The following three photographs illustrate the effect and coverage at three focal lengths. These are approximates rather than exact values.
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| 135mm | 200mm | 230mm |
| Click on the picture to see a full size one | ||
When you point the lens to the sun or a very strong light source, lens flare and ghost may occur in your photograph. The left photograph below shows such an effect. The area near the bright spot is washed out. In fact, flare occurs even though the strong light source is not in the photograph. Flare occurs due to light bouncing off the glass surfaces of the lens rather than being transmitted through. As a result, image contrast and color are reduced.
The right figure below illustrates another effect, ghost, a string of color dots appearing in the photograph. The wash-out effect (i.e., flare) is still there in the upper-left corner, but is not as strong as the one shown in the left figure. However, there is a string of dots, usually in green, purple or violet. These dots have the shape of the aperture of the lens. Most low cost zoom and wide angle lenses, including the one on Nikon Coolpix 950, suffer this problem. In a better lens, surfaces of glass are multicoated with special chemicals to prevent flare and ghost.
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| Lens flare and ghost | |
| Click on the picture to see a full size one | |
To overcome this problem, please do not point the lens toward or near a strong light source. If this cannot be avoided because that is your favorite scene, try to hold a paper or use your hand to block the incoming light. It usually partially solves this problem.
Also note that the right figure has vignetting. This is because I stacked the polarizer on the Haze-1 filter and zoomed out. To avoid this vignetting problem, do stack filters on top of each other.
There are two types of obvious lens distortion: barrel distortion and pincushion distortion. Both types of distortion are slightly visible with the on-camera zoom lens.
Since the converters are add-on lens rather than a true wide angle or telephoto lens, optical quality is lower than that of the on-camera lens when they are used. As a result, both distortions are visible.
Normally, wide angle lenses, and hence wide angle converters, exhibit barrel distortion. The following is taken with the wide angle converter mounted (24mm). Barrel distortion is clearly shown near the left edge. Moreover, lens flare is shown near the upper-left corner because the position of the sun is just outside of that corner.
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| Barrel distortion |
| Click on the picture to see a larger one |
On the other hand, telephoto lens, and hence tele converters, usually exhibit pincushion distortion. The following is taken with the tele converter mounted (230mm), which is actually the last photograph used for illustrating different focal lengths above. A yellow line that connects the two endpoints of the roof is drawn. Comparing this line and the edge of the roof, you should see pincushion distortion. If it is difficult to visualize, please click on the picture to view a full size photograph.
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| Pincushion distortion |
| Click on the picture to see a larger one |