Power tip for your cameras:
Turn off the function for “Auto LCD Brightness” if your camera has it. Instead, set the picture review LCD to manual brightness, in the middle, and leave it there.
Auto LCD brightness often leads to you misinterpreting your images. An image can look waaay too dark on the LCD, leading you to do it again and expose brighter – only to find out later that the original image was fine. This can be quite a dramatic effect: be careful.
Of course you can also use the histogram to interpret the light. But I would start with getting a consistent LCD display.