How are you making the determination that the colors are different?
That may sound like a silly question and you might think "because I'm looking at them side by side" -- but I'm really asking something more specific.
The first time I bought a DSLR (after having shot film my whole life), I thought the camera was under-exposing my shots... so I starting deliberately increasing the exposure. I ultimately discovered that my original (non-adjusted exposures) shots were fine, but the screen on the camera was set a bit dim so the photos "looked" underexposed to me on the camera, but once imported to the computer, they were fine.
When making comparisons, you can't trust what you see on the LCD screen of the camera in terms of color fidelity. Make sure you've imported them both to the same computer and are comparing them on the same monitor (becuase even different computer monitors will display colors differently.) I now own a device which color-calibrates my monitors and printers to make sure the colors are accurate and consistent.
Canon cameras support something they call "Picture Style".
The "standard" picture style will moderately saturate colors (not so much to be obnoxious, but enough to make the images slightly more vibrant than the true colors of the scene or subject.)
There's a picture style called "neutral" which does the least adjustment (closest to true color) as well as "faithful" which is basically identical to "neutral" except meant to be accurate in daylight color balance (outdoor sun during mid-day). But both of these are intended for situations where you intend to import to a computer and then adjust them to your liking.
Additionally... altering the white balance will have a huge impact on the colors. I find that if I just slightly warm the color temperature (or pick a white balance setting such as "cloudy") then the camera will slightly boost the yellow/orange on an image (because images shot in cloudy overcast conditions generally look a bit too "cool") and this has the effect of really punching up the greens and reds -- making the images appear as if I've increased the color saturation even when I haven't touched it.
I never worry too much about color accuracy because there's almost no such thing as an image I plan to use for anything that hasn't been adjusted on the computer (including things like white balance and color).
For more info on Picture Style, see: https://www.learn.usa.canon.com/app/pdfs/quickguides/CDLC_PictureStyles_QuickGuide.pdf
I didn't link any articles on White Balance (something else you might check) because those instructions tend to be specific to the camera model. But the idea behind white balance is that "light" will have a color cast to it (some light is very slightly blue... or very slightly green... or very slightly orange (or sometimes very strongly color cast). And when that happens, the light on your subject actually changes the perceived color of that subject. The "white balance" adjustment is designed to let you tell the camera what sort of lighting conditions you have, so that the camera can try to do the correct thing when adjusting for it. By default there's a setting called "auto". You can find lots of articles that describe the difficulties of using "auto" and that very often it will make the wrong guess. It's usually better to just set the white balance based on the conditions that you know you have.
Tim Campbell
5D III, 5D IV, 60Da
