I have Rollei 35mm 50mm 1.8 lens (sigapore version). The push pin on the bottom of the lens is broken such that when I push it the diaframe move down but when I release it, it's never return to wide open state.
I love fixing things but I don't have much knowledge of fixing lens or camera. I wonder whether it is difficult to repair myself (since the lens is not expensive)? Can you recommend any repair giude websites or books.
I am not familiar with this particular lens. The most common cause of this problem is oil getting onto the blades and making them stick, either open or closed depending on the design of the camera and lens (and on luck).
The cure in a general sense is to remove the front end of the lens and clean the oil off of the blades and the actuating mechanism. You might want to go ahead and give this a try.... you probably can't get the lens professionally serviced for less than the cost of replacement (although Rollei lenses being less common might cost a bit more than some others, so it's worth asking), and if you're going to have to replace it anyway then you have nothing to lose by trying to fix it.
I don't have a guide or specific advice for this lens - maybe someone else does.
