Perhaps from a need for closure I don't like to toss something away until I have exploited all of its possibilities. How can one get a better one of anything when one hasn't fully learned to use the one you've got? In the mid-1980's the Navy gave me an XT computer. Actually they gave it to our office but no one else wanted it. They thought it was a terminal to the mainframe. Which technically it was. Among other things. It had an 8086 processor, 256 kilobytes of RAM, and the first hard disks on mass-produced computers, 10 megabytes. Within a few months I learned everything it and the software that came with it (Lotus 1-2-3, Dbase III+, Wordstar, DOS 2.11) could do. And I used almost every feature.
I felt put upon when we were given 80286 machines. With color screens no less. It meant that I had to learn a whole new machine and suite of applications. With one thing and another, I never felt that I ever completely mastered all the possibilities of the 286 before the 386 machines came out. That was when I came to regard the march of progress as having passed me by. From then on I was just hanging on, doing the best I could. But not in charge. Now I have come to accept that one merely uses the new machines, one does not master them.
It is not just computers. One used to repair and adjust automobiles. One summer I helped Harvey completely overhaul a Volkswagen beetle. We knew everything that was in it and how every bit of it worked. Now cars have black box electronic components like aircraft do. One checks that a component is working using an electronic analyzer. If it isn't, one replaces it. One does not 'fix' or adjust anything.
It is the same with the camera. It is beyond imagining that I could ever know how it works. But it is possible to master the user's manual and how to use its features. It is amazingly complex and the user's manual runs to 200 pages of misleadingly written prose. Learning all about how to use it is far from trivial. And this is an advanced amateur camera. Imagine what the cameras for professionals are like - aside from huge, heavy, and amazingly expensive.