Category Archives: lens

AF problem? Adjust the zoom-brush!


A lot of used (and repaired) zoom lenses have autofocus problems, front focus or back focus. Case the lens has been disassembled before, the problem can be caused by the non-adjusted zoom-brush. What does the zoom-brush have to do with … Continue reading

Posted in 17-55 F2.8 IS, lens | 10 Comments

Polishing a damaged lens – cerium-oxide


Normally I repair only Canon DSLR-s – but sometimes I cant resist to other optical devices either. I had to clean a DLP (!)  video-projector for my sons school – it was terrible, a half kg of dust in a … Continue reading

Posted in dirty, dust, lens, tools | 3 Comments

Glued screws – when the serviceman get’s angry


I have got a Sigma 300 mm F2,8 lens from a customer, which has some dirt in the inside. A lens element was dirty or some fungus on the surface. (As a supplementary information I was told, that on the … Continue reading

Posted in DIY, lens, tools | 1 Comment

DIY suction cap for lens disassembling


In fact, I didn’t wanted to make it. I just wanted to buy a tool for disassemble a very expensive lens (a Canon 85mm F1.2). Unfortunately, the tool was not available in short time. Here is the link to the … Continue reading

Posted in DIY, lens, tools | Leave a comment