I recently acquired a late production Praktica Super TL, number 500957 out of aprox. 508000. It came to me with a stuck shutter, but after some cleaning and exercise and prodding the camera fires reliably. Except when set to 1/125 and pointed upward. Without exception firing the shutter when set to 1/125 and tilting the camera upward - the mirror stays up and won't return. If I rotate the shutter dial to 1/60 the mirror will return. If I fire the shutter on any other speed with the camera pointed upwards, the mirror returns like normal. But it will always stay up when set to 1/125. I'm a bit baffled why this would happen on only one shutter setting, and what causes this. The camera has been serviced in the past which suggests whoever owned it had previously had some sort of problem with it - perhaps related to the issue I have with it. If anybody has any ideas I'd appreciate hearing them.