Digital Tele
The on-camera zoom lens can zoom in and out optically by using the optical formula built into the lens. On the other hand, digital tele, or digital zoom, can do the same by magnifying the existing image using software. Nikon Coolpix 4500 has a 4x digital tele. Thus, this capability effectively creates an optical/digital zoom of focal length from 7.85mm (38mm - 35mm equivalent) to 128mm (620mm - 35mm equivalent). In terms of telephoto power, the 2x digital zoom is equal to the Nikon 2x Tele Converter TC-E2, while the 3.0x extends the focal length to 456mm and is equivalent to the Nikon 3x Tele Converter TC-E3ED. Digital tele can only be used in M, A, S and P modes.
Although digital tele can increase the focal length without the use of a tele converter, there is a price to pay: lower image quality. More precisely, digital tele means taking the center portion of an image and blow it up to the desired resolution using software. The following figure shows the relative sizes and area of 1x, 2x, 3x and 4x digital zoom can cover. For a 2x digital zoom, the 2x area is taken out from the 1x image and blown up using software to the size that is equal to the size of the 1x image. This "blow-up" process adds extra pixels; but, it does not add details because the image details are limited by the area of the original image.
The following images illustrate the effect. The left one is taken with a 2x tele converter (i.e., Nikon TC-E2 Tele Converter), while the right one uses 2x digital tele.
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| 2x Tele Converter | 2x Digital Tele |
| Click on the image to see a larger one | |
The following two images show the center parts of the original images. The image definition of the one taken with digital tele is poor. By the way, both images are not sharpened; but, sharpening will not help very much.
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| 2x Tele Converter | 2x Digital Tele |
The next two images show the upper-left corner of the original images. The sharpness of the tele converter near the upper-left corner is obviously inferior to the center portion; but, it is still much better than that of digital tele.
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| 2x Tele Converter | 2x Digital Tele |
Therefore, if image quality is your primary concern, digital tele is not the way to go. A 2x tele converter is a better solution. In these two images, those taken without digital tele contain more details and are sharper.
Important Notes
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To use digital tele, you must first use the zoom button T to zoom the lens all the way in (to 155mm). Then, hold the T button for more than two seconds. The zoom scale becomes yellow and the scale indicator moves to the right portion indicating digital tele is in effect. See the image below. You can use buttons W and T to select a digital tele position. Holding button W until the zoom scale is shown in white returns the camera back to optical zoom. Turning the camera off deactivates the digital zoom.
Digital zoom can be disabled and enabled in P, A, S and M modes. To do so, follow the procedure below:
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Note that if digital tele is currently enabled, the left of the Digital Tele will show ON. Otherwise, OFF indicates digital tele is disabled.
Use the up and down arrow to highlight the option you wish to use and press the multi-selector down to make a selection. Once a selection is made, the menu returns to the left image in Step 3. At this point, press the MENU button to return to the shooting mode.
However, if you do not wish to make a selection, then press the MENU button to return to the shooting mode. Or, you may use the left arrow of the multi-selector to return to the previous menu for other options.
Note that turning the camera off will not reset this digital zoom option. You need to follow this procedure to enable or disable digital zoom.