bedouin wrote:
I use 3 different Pentax cameras- K-3, K-1 and 645Z. No matter what mode I use (landscape, natural, portrait, vibrant) and adjusting the colors, contrast, etc., I get unsightly reflections in daylight on red and yellow flowers. My eyes do not see this, even in the viewfinder or live view. A polarizer does not help nor does adjusting ISO. Now, shooting the same flowers in shade does not produce this undesirable effect.
Any suggestion how to eliminate it?
These images look like you have exceeded the camera's ability to record bright, highly saturated color(s) - otherwise known as channel clipping.
I've gotten decent results with similar highly saturated colors by using a ColorChecker Passport, which changes the color response curve of the camera's raw files and slightly lower exposures. However, if the channels are severely clipped, the only real alternatives are to a)avoid shooting in bright sunlight, b)slightly underexpose the shot to minimize clipping, and c)shoot raw, which will provide a bit of headroom and "clipping resistance" as well as better results if you choose to underexpose a bit.