If people learn through their mistakes I ought to be a photographic genius by now!
Unfortunately, I'm not. In the vain hope of getting some value out of my assorted cock-ups I've decided to post them here to amuse you lot.
On a motorcycle tour in Wiltshire I'd stopped for the evening at a farm offering bed and breakfast. I'd taken a lot of pictures of some lovely scenery with my manual-wind Pentax that day, finishing the roll of film which was still in my camera. I was planning my next day's travel when I heard what sounded like shots outside. I looked out of the window and saw the sky lit up with fireworks. I quickly grabbed a fresh roll of film and opened up the camera to find that I hadn't rewound the roll when I'd finished it earlier in the day... In the event I was lucky and only lost two frames to fogging.
At a model shoot the studio flash unit was set up to work at F16. I shot for a while using my 55mm standard lens then slipped a 2x tele-convertor on to do some close-cropped head-shots, opening up to F8 in the process. When I reverted to just the 55mm on its own again I completely forgot to stop back down. As I was using slide film the resulting shots (about eight of 'em before I noticed!) were so over-exposed it looked like the poor girl had been dipped in bleach! I wish I could say I'd only done that once...
A similar problem with aperture happened in the darkroom. After setting up, focussing and doing my test strips I thought I'd just have another quick focus to get it reallysharp. I opened up from F11 to F2.8, dialled the filters out and stuck a focus finder on it. All was well, so I went ahead and did the print... ...at F2.8 with the filters out. Of course, the resulting print was completely black! I wish I could say I'd only done that once, too...
At my first model shoot I was using the manual-focus (manual-everything!) Pentax. I knew I should focus on the models' eyes, so I did. Unfortunately I then didn't reframe the shot before taking the picture. This meant that in almost every shot the models were cut off at the ankles and yet had a good metre visible above their heads!
I can guarantee that this page will fill up further as time goes by...!