Weather-Sealed DSLR Camera Comparison

Since you read this far, there is probably more than one model with the major features that fit your photographic needs. So the final decision is going to be based on minor details. Some of these are quite subjective such as the way a camera body fits in your hands. For those who just landed here, you can review the major differences on the previous page.

Naturally, every DSLR here as PSAM modes with program shift to obtain equivalent exposures. All the Pentax models also feature a Sensitivity-Priority mode which gives direct control over ISO. The Pentax K-7 and K20D have the most sophisticated set of modes. The P mode is referred to as Hyper-Program because it can be shifted into aperture-priority or shutter-priority using the two control wheels. A press of the green button returns to program mode. These is also a TAv mode (Time-Aperture) which lets the camera select the ISO speed based on user-selected shutter-speed and aperture values. The M mode of the K-7 and K20D is referred to as Hyper-Manual because the exposure can be preset to the metered-value using the green button. Hyper-Program can be customized to favor average settings, fast-shutter speeds, narrow apertures or optimal lens sharpness. There is also an X mode which uses the flash sync-speed. These modes are truly outstanding features of the Pentax K-7 and K20D.

Except for the Nikon D300S, every DSLR compared here as an Auto-ISO setting. The Canon EOS 7D selects between 100 and 3200, an aggressive range which may limit print sizes. The Olympus E-3 and Pentax K200D have shorter fixed ranges while the Pentax K-7 and K20D both have customizable ranges with settable minimum and maximum. This way one can decide the range of acceptable ISO.

For ISO sensitivity, the range itself can often be misleading. It matters more which are usable ISO settings than which ones are available. Many cameras hide their full ISO range for this reason, as going beyond the normal range shows a distinct drop in image quality.

Based on available samples, there are virtually no differences between noise levels until ISO 400 for all these cameras. After that point, the older E-3 and K200D trail behind their newer competitors. The K20D and K-7 share the same sensor which is slightly noisier than the 7D which is also noisier by a small margin compared to the D300S. These are still all state of the art DSLRs and - although there - differences are rather small. Most differences are actually caused by image processing as opposed to inherent properties of the image sensor. It is worth repeating that comparing noise alone is not very useful as its visibility depends on resolution as well. With 50% more pixels than the D300S, the 7D is allowed and expected to show more image noise.

The standard exposure-compensation (EC) range is from -2 to +2 EV in 1/3 stop increments. The Canon 7D and Pentax K20D can do a bit better with a -3 to +3 EV range. The Nikon D300S, Olympus E-3 and Pentax K-7 have a much better range going from -5 to +5 EV. Bracketing is a similar story with the D300S capturing up to 9 images in one bracket, both Pentax capturing 5 images and the rest 3 images. The K-7 and K20D can also bracket for white-balance, saturation, hue, contrast, sharpness and high/low-key (K-7 only).

Exposure locking (AEL) and focus locking (AFL) can be done automatically with a half-press of the shutter or using a AE-L/AF-L button. The K200D only has an AE-L button that takes care of these functions. The remaining cameras also have a AF-On button which serves to trigger autofocus and lock focus in a separate action, thus providing more flexibility in setting up a shot. All these cameras other than the K200D can customize the behavior of the AF-On and AE-L buttons.

White-balance (WB) compensates for the color of various light sources. The outstanding WB feature among these camera is Pentax's digital white-balance preview. With this feature, you can preview the same image using each WB setting with fine-tuning applied. With every other DSLR, finding the right white-balance setting requires taking multiple shots.

Table 4 - White Balance Controls
Canon EOS 7D	Auto, 6 presets, custom, kelvin. Fine-tuning in 19 steps along B-A or M-G axis. White-balance bracketing, 3 frames.
Nikon D300S	Auto, 7 presets, custom. Fine-tuning along B-A and M-G axis. White-balance bracketing up to 9 frames.
Olympus E-3	Auto, 8 presets, kelvin, custom. Fine tuning along R-B and M-G axis in 15 steps. White-balance bracketing, 15 steps.
Pentax K-7	Auto, 8 presets, custom. Fine-tuning along B-A and M-G axis. White-balance bracketing, 3 frames.
Pentax K20D	Auto, 7 presets, custom. Fine-tuning along B-A and M-G axis. White-balance bracketing, 3 frames.
Pentax K200D	Auto, 8 presets, custom. Fine-tuning along B-A and M-G axis.

Self-timers are available with all these cameras. There is at least a short-timer suitable for preventing camera movement during long exposures and a long-timer suitable for getting into group photos. The Pentax DSLRs automatically lift the mirror when using the short-timer and disable stabilization. This perfectly matches the most common usage of the short self-timer. There are also delayed remote timers with the 7D, K-7, K20D and D300S.

Live-view is listed as a feature to most of these cameras but the only one to implement it fully is the Canon 7D. It shows 100% coverage but also accurately displays exposure and white-balance. The Nikon D300S and Pentax K-7 also show 100% coverage but they do not show exposure correctly part of the time. The K-7 does have the advantage of allowing its LCD to be color-adjusted to improve its color accuracy. Although the K20D officially has live-view, it is better ignored.

The rear LCD of these weather-sealed DSLRs vary in size from 2.5" for the E-3 to 3" for the 7D, K-7 and D300S. This difference is size is not as significant as is the difference in resolution. All the 3" display feature 920k pixels, four times the resolution of the smaller screens. This make live-view more suitable for judging focus and also requires less zooming in order to check the sharpness of captured images. It is worth mentioning that checking anything other than sharpness, such as color and contrast, on a rear LCD display is never accurate compared to using a good computer display.

All these cameras, including the entry-level K200D, also have a top-mounted monochrome LCD display that shows camera status. These displays are backlit for viewing at night except on the K200D. A unique feature of the D300S is that the top display also shows the space available on the card when the power is off. It indicates just as clearly when there is no card inserted.