Pentax Q Viewfinder
Like some competing models, the Q does accept an optional, external viewfinder eyepiece, however. Faced with a choice of an optical, or an electronic viewfinder accessory, Pentax took the optical route. That decision brings advantages and disadvantages. Since the accessory is entirely optical, it doesn't require complex (and perhaps delicate) electrical connections to the camera body. It also uses no battery power, providing a significant advantage over framing images on an LCD display. Unlike an electronic viewfinder, there's also no need to worry about lag, resolution, contrast, and dynamic range: what you're seeing is a real-world view, and we can report that the Pentax O-VF1 accessory provides a clear, sharp, bright image that makes for a pleasing shooting experience.
On the flip side, though, since it has a separate optical path, the O-VF1 suffers from parallax error when shooting nearby subjects, and its focal length can't be adjusted to match that of your lens. This makes it useful only when shooting with the 47mm-equivalent 01 Standard Prime lens, for which the O-VF1 includes framing guidelines. Nor can the O-VF1 offer a preview of focus, white balance, exposure settings, and the like; the only utility is for framing your subject, if it's sufficiently far-enough away not to be subject to parallax.
It's also surprisingly expensive. Where competing optical viewfinders cost around US$100-130, the O-VF1 will set you back around US$250. There's no question that it's a solid, high-quality design, but given its pricing and relatively limited utility, it's not an accessory we'd recommend to most Q shooters. (If you plan on shooting near-exclusively with the 01 Standard Prime lens, though, it might be worth considering.)
The O-VF1 mounts in the camera's hot shoe, so note that you can't use an external flash strobe at the same time as the viewfinder accessory, at least not without resorting to a bracket of some kind (which would likely increase the severity of parallax error, the further the viewfinder was moved from the central axis of the lens.)
Pentax Q Full-time Live View
By its nature, the Pentax Q is always in "Live View" mode: In that respect, it's like any point & shoot digicam with a rear-panel LCD that works as its viewfinder. The difference with this camera is that it has interchangeable lenses. The Q's display has a reasonable 460,000 dot resolution, which together with a focus assist zoom function makes it reasonably easy to focus manually. It also has wide viewing angles of 170 degrees both horizontally and vertically.
Several display modes are available, allowing for overlays including a live histogram, several grid displays, and a blinking under / overexposure warning. The information display in record mode includes shutter speed and aperture, ISO sensitivity setting, exposure mode, flash mode, metering mode, focus mode, number of available images, resolution, aspect ratio, shake reduction, drive mode, white balance, focus confirmation, battery status, etc. Note, though, that the histogram function isn't available in Movie mode.
If you're shooting with the O-VF1 optical viewfinder accessory, you can also disable the LCD display to save power (and prevent distraction), or have it serve as a control panel display instead.
Viewfinder Test Results
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