That's happened to me and it's almost always an over exposure issue. Use exposure compensation to dial it back and if your camera has a "vivid" setting, that would help also.
Use a polarizing filter and you will notice how much better the color will show. Takes the reflection off of the leaves and makes the color much brighter.
I understand the request for pictures for evaluation, but don't understand the respect comment. Unnecessary.
Lonewolf 456 - I don't either. No matter what, there always seems to be some ###### on this site that needs to make some unnecessary and unwanted comment. I just don't get it. It happens all too often, and it's not called for. Some new photographer to this site is just asking a simple question to get some feedback about something they don't understand and along comes #### running off at the mouth(keyboard) with inappropriate comments. I was under the impression that this site was about sharing our experience and skills with other upcoming photographers. My mother always taught us when we were kids, if you can't say something nice, don't say anything. I think that the administrators or monitors of this site need to put out a warning to the person(s) making unwelcome comments that if they continue to make crass remarks they will be banned from this site. I for one am sick and tired of having to see inappropriate comments.
Bright sun today, Nikon P900, Bright colors of red, yellow, orange do not appear in pictures.
I prefer to shoot autumn color in overcast-to-misty conditions, but a polarizer will help in all conditions, especially (as noted) in direct, bright sunny ones. Also, try under-exposing by 1/3 or 2/3 stop or more. Following the basic keep-the-sun-over-your-shoulder rule helps, too .