Canon EOS-1D Mark IV Viewfinder
The Canon EOS-1D Mark IV's viewfinder hasn't changed from the 1D Mark III. According to the company, the Canon 1D Mark IV's pentaprism viewfinder has a coverage of approximately 100% (which agrees fairly well with the ~99% coverage we measured in our test results below). Magnification is 0.76x (-1 diopter with 50mm lens at infinity), eyepoint is 20mm, and a diopter adjustment range of -3 to +1 is provided.
The focusing screen is user interchangeable, with a total of 13 screens being offered, and an Ec-C IV laser matte focusing screen is included. In addition, the eyepiece cup is also user interchangeable, and alternatives to the standard Eyecup Eg with its soft rubber surround include an anti-fog eyepiece, and a selection of dioptric adjustment eyepieces for photographers whose eyesight is beyond the correction abilities of the viewfinder itself. The 1D Mark IV is also compatible with Canon's Angle Finder C attachment.
A built-in eyepiece shutter is also provided, to prevent ingress of light that might affect metering or exposure when you aren't using the viewfinder such as in Live View or self-timer modes. The active AF point is indicated in the viewfinder, and the brightness of the AF point indication is manually adjustable in two steps. The viewfinder also includes horizontal and vertical displays that provides a wide range of variables including ISO sensitivity, shutter speed, aperture, and more. A couple of minor changes have been made to the horizontal viewfinder display, including the addition of a "D+" indicator to show when highlight tone priority is active, and an extra '1' digit at the start of the ISO speed field.
See below for callouts of the information available in the optical viewfinder (diagram courtesy of Canon USA):
Viewfinder Test Results
Coverage
Very good accuracy from the optical viewfinder and LCD monitor in Live View mode.
Optical Viewfinder | LCD Live View |
Testing with a low-distortion macro lens to minimize the effect of lens distortion, we measured the Canon 1D Mark IV's optical viewfinder at just over 99% coverage accuracy. The resulting image was very slightly tilted with respect to the sensor, which is unfortunately quite common with optical viewfinders. Live View mode using the LCD also showed about 99% coverage, and of course, wasn't tilted.
Follow Imaging Resource