EVF/LCD units are small displays just like a computer's flat panel display. Unless you're willing/able to calibrate the EVF/LCD with neutral tri-tone and color checker targets, the best you can get out of an electronic viewfinder device is a first order approximation of what the camera's rendering system will produce in the output files. Most cameras lack any kind of sophisticated way to calibrate these displays, in my experience, with some exceptions.
On the Olympus E-M1 (and maybe other models), you can adjust the EVF and LCD displays brightness, saturation, and color balance independent of the JPEG settings to achieve the best view for your eyes. This allows for a degree of calibration of the display so that the JPEG engine can be rendered accurately, or at least predictably.
You can also enable or disable Live Boost (now in multiple strengths with fw v3.1) for different situations so that the EVF and LCD can either track the exposure settings with an approximation of the resulting JPEGs or display a uniform brightness for best framing/focusing in dark circumstances.
So with some cameras, you can get close with the EVF/LCD and rely upon it for judging exposure and color balance to some degree, but you have to know your camera and can only rely upon it for that if it has enough adjustability and features to support such estimation. In most cases, it's best to consider the viewfinder as a focusing and framing device only and use the histogram and saturation 'blinkie' displays to determine proper exposure; leave color balance issues to post processing.
Have you pondered over the color saturation in your camera's EVF? Do you think more colorful EVFs strain the eye and distract from the subject?
Certainly an overly bright and/or overly saturated display monitor gives an unrealistic view of the subject and can be tiresome to look at. I prefer a display that presents, in its base configuration, a neutral rendering of the subject matter at a reasonable illumination: that is least tiring to the eye and allows adjustments to color balance, saturation, sharpness, etc, to be estimated best.
I liken these attributes of an EVF/LCD to the optical quality of an SLR viewfinder. I was lucky enough to start my SLR photography with a Nikon F Photomic FTn and Nikkor 50mm f/1.4 lens way back in the late 1960s, a camera that had a superb 100% coverage viewfinder and state of the art optical quality. I remember vividly from those days picking up some less expensive SLRs and being appalled at how much distortion there was, and how much of the actual field of view was not represented in the viewfinder.
To me, those things were both tiring to my eye and distracted from the subject, just like a low quality EVF/LCD with a slow refresh rate, bad dynamic range, low resolution, out-of-kilter colors and saturation, and insufficient illumination are today.
G
