Nikon D80 Viewfinder
Like most dSLRs, the Nikon D80 uses an optical viewfinder that works through the lens. (The LCD monitor is for image playback and accessing the menu system only.) A diopter adjustment dial adjusts the focusing of the viewfinder optics to accommodate eyeglass wearers, and the viewfinder also has quite a high eyepoint (meaning you can see the full frame with your eye a good distance from the rear objective). The 19.5mm eyepoint is fairly good, but I personally (Dave speaking here) do still end up having to press my eyeglass lens against the rubber eyecup in order to see the full frame clearly. The -2.0 to +1.0 diopter adjustment range of the viewfinder optics isn't nearly enough to accommodate my own very nearsighted (20:180) vision, but is more than ample to handle my "computer glasses", which are set to provide good focus for my eyes at a distance of about 18-24 inches. (Frankly, people as nearsighted as me are unlikely to ever walk around without some degree of vision correction, so we think the dioptric adjustment range of the D80 should be more than sufficient for most users.)
One big plus about the D80's viewfinder is its size: It's basically the same viewfinder as used on the D200, and is very noticeably larger than the viewfinders on other Nikon consumer SLRs. (The D70/D70S and D50, for instance.) The illustration above, courtesy Nikon, compares the size of D80's viewfinder with those of the Canon Rebel XT and the Sony A100 (both of which are approximately the size of the D50/70 screens). While I dislike having to press my eyeglasses up against the eyecup, all of us at IR really like having a larger viewfinder image to look at.
Here's another, more subtle point about the Nikon D80's viewfinder: It uses a true pentaprism, rather than the pentamirror arrangement that's all but universal in consumer-level SLRs. The reason this is important is that pentaprisms are much brighter. This is because a convenient trick of optics makes prisms 100% internally reflective, so no light is lost as it bounces around inside and back out the eyepiece. Even the best mirrors typically pass only 96-98% of the light falling on them. In a pentamirror, with three reflections required to bounce the light into your eye, this means that anywhere from 6 to 12% of the light is lost, making for a noticeably darker viewfinder image.
An illuminated display inside the viewfinder provides detailed exposure and camera information, including black and white mode, battery low, and "no memory card" warnings, focus confirmation, flash and AE lock, Auto ISO, shutter speed, aperture, metering, battery status, exposure and flash compensation, white balance/exposure bracketing indicator, frame counter, flash ready light, and eleven sets of focus brackets. When activated, the view also includes an alignment grid, useful for lining up difficult shots. A large circular outline in the center of the view indicates the Center-Weighted metering area. The optional grid (enabled via a Custom Menu setting) and focus area indicators can be set to illuminate briefly when the shutter button is half-pressed, although the illumination isn't too bright, and is easily missed against a bright background. (Presumably though, if the background and subject are that bright, you'll be able to see the dark viewfinder markings easily enough without the illuminator.)
Viewfinder Accuracy Test
Good accuracy with optical viewfinder.
|18mm eq., Optical||135mm eq., Optical|
The Nikon D80's through-the-lens optical viewfinder was pretty accurate, showing 95-98% frame accuracy, depending on the zoom setting. (The variation is likely the result of the barrel/pincushion distortion from the lens.) This agrees with Nikon's own specifications, but as always, we wonder why DSLR makers can't design 100% viewfinders as a matter of course.
Like those on essentially all digital SLRs, the LCD panel on the D80 isn't usable as a viewfinder. It does, however, provide a great deal of information about your pictures after you've shot them. A variety of playback options are offered, including image-only, six flavors of overlaid information, a 4- or 9-image thumbnail display, and a zoomed playback mode with variable information. The screenshot at right shows several of the information displays that are available.
Its playback screens were one of the things we liked most on the D200, so we were very happy to see a lot of that functionality carried over to the D80 as well.
Of the various screens, one of the more interesting options on the Nikon D80 is the histogram screen. Histogram displays are common on professional digital cameras (and many amateur models now as well), regarded as almost mandatory by many pros for evaluating exposure levels. A histogram is simply a graph of how many pixels there are in the image at each brightness level. The brightness is the horizontal axis, running from black at the left to white at the right. The height of the graph shows the relative number of pixels having each brightness level. This sort of display is very handy for determining under- or overexposure. Ideally, the histogram would stretch across the entire width of the display, using the full range of brightness values available. An underexposed image will have a histogram with all the data lumped on the left-hand side, with nothing reaching all the way to the right. Likewise, an overexposed image will have all the data lumped on the right hand side.
On the D80, Nikon appears to have dispensed with the luminance-only option for the histogram display, opting instead to make the RGB+L histogram display the default. As seen at right, this display graphs the overall brightness (the white graph) as well as brightness values in the Red, Green, and Blue channels separately. Having the three colored histogram graphs available makes it much easier to tell when you're in danger of saturating highlights with strongly colored objects, and also gives good guidance as to whether you've achieved a neutral white balance or not.
A histogram display is very helpful in telling whether you've got the exposure right, but to my mind isn't adequate by itself. With digital cameras, it's very important not to blow-out the highlights in a picture (they're similar to color positive film in that respect), since once you hit the maximum brightness, the image just saturates, and any highlight detail will be lost. A histogram display does a pretty good job of telling you how the image as a whole is doing, but what if there are just a few critical areas that you're worried about for the highlights? If only a small percentage of the total frame is involved, it won't account for many pixels. That means any peak at the "white" end of the histogram graph would be pretty small, and easy to miss (or just plain invisible). What to do? The folks at Nikon recognized this problem some time ago, and so have provided another special display mode on the D80 (as on most of their dSLRs) that they simply call "highlights," accessible via the Playback settings menu, under "Display Mode." This mode blinks any highlights that are saturated in any of the color channels. It does this by taking the nearly-white areas on the LCD and toggling them between white and black. (This screen shot is actually borrowed from our D200 review, the function works identically on the two cameras.)
One option sadly not copied from the D200 though, is the ability to do a highlight blink based on the individual color channels: On the D80, the highlight blink only shows you areas where the overall luminance is approaching saturation.
The D80 also offers the D200's greatly excellent options for display magnification, but does so via a somewhat simpler interface. You have the normal thumbnail or normal-sized displays available, but can also enlarge the display up to 25x to examine critical focus and framing. Pressing the Magnify button enables zoomed playback, and each subsequent press of it zooms in a step closer. Pressing the "unmagnify"/Thumbnail button zooms you out. Any time you're zoomed in, you can scroll around the magnified image by using the Multi-controller. This interface is potentially slightly slower than that of the D200, but much simpler, not requiring the simultaneous manipulation of the zoom buttons and Main Control Dial.