I work as a crime scene investigator from just outside Chicago. My dept replaced my old camera (Canon Rebel T3i) with the Nikon D7200. Here's my issue: I work midnights, so low light photography is primarily what I do. I use manual settings for a majority of my photos. With the newly assigned D7200 after I take a photo, the camera automaticly changes my settings. Is this something I am doing wrong? Or camera/hardware issue? I'm familiar with the "exposure triangle" as well as stops, but can't seem to figure out what it's doing.. Example of Typical settings I would have with my old Canon: ISO Varies 600-~ depending on lighting f11-23 40-50 typical Shutter speed External flash@45 degrees. If I was to set these peramiters I would take a photo and it would come out properly focused and exposed. The next photo, the camera will change my settings to a shutter speed of 1/9 or lower of a second. Or change my f stop to 5.6. Again, I am familiar with the exposure triangle. By no means am I a professional photographer. I need to take quality and accurate photos to either prosecute or exonerate a person. Any help is appreciated Thanks.