Paul C. Buff, Inc. Technical Forum

I was shooting a model today in front of a backdrop. I was shooting on f/22 and 250, which is the same settings I have been using for years. The photos gradually became brighter and brighter until completely blown out and the settings were completely the same. Any clue if this is a lighting issue or a problem with my camera? Any help would be greatly appreciated.

Double check your exif data to be sure your settings stayed the same, including ISO (I have had rear dials scroll when by my side).

If so, are you able to replicate the problem? Can use a meter to see if and by how much drift there is?

I double checked all my data and it was the same including ISO. I do not have a meter to check. I was wondering if it could be a bulb problem? I have had these lights for 4 years and have never replaced any of the bulbs.

I would triple-check the EXIF data, really sounds like a camera settings change. I've had that sort of thing happen to me too. Also, how many frames between the last good exposure and the totally blown-out frame? Were the lights being moved closer to the subject & background?

This would not be a function of the bulbs. If the exif matches start to finish, and there was no change in placement or modifiers, then the light(s) may need service. I would doubt all lights would do the same thing, so I would check each light individually at 1/16 power or so and see if one flashes brighter than the others (this would be obvious to the naked eye).