Category Archives: Canon lens

The mystery of NO FOCAL LENGTH on flash


The customer has got a used Tamron 17-50 F2,8 lens, and realized that using with a Canon strobe, there is no change on the strobes display, it shows always 17mm focal length. I was sure that there has to be … Continue reading

Posted in Canon lens, Tamron lens | 7 Comments

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 | 13 Comments

24-105 F4 IS – damaged stabilizer


A few weeks ago I repaired a used 24-105 for myself. I have purchased it in a box in thousand pieces for a bargain price. Everything was ok – excepting a strange noice from the stabilizer when switching on and … Continue reading

Posted in 24-105 F4 IS, EF lens, EF-S lens | 11 Comments

F-words repairing Canon lens


F like F…. FLEX. The f.cking flex. I had to repair a 17-55 with aperture problems. The lens started to close the aperture more and more at certain zoom values. Simple case, isn’t it? You have to change the flex. … Continue reading

Posted in 17-55 F2.8 IS, Canon lens, EF-S lens, test bench | 8 Comments

Canon 24-105 F4 broken flex – why exactly there?


You have probably seen a lot of 24-105 lenses – the flex cable breaks after a certain time of using – and ALWAYS on the same place. And on that position always appears a tiny broken line in the middle … Continue reading

Posted in 24-105 F4 IS, Canon lens | 8 Comments

Canon EOS – no communication with SOME lenses (70d)


It was a Canon 70d – but as we have seen at the end, in fact could be any camera. The owner told me, that the camera can work with different EF (full frame) lenses, some Sigma lenses – but … Continue reading

Posted in 70d, Canon camera, EF lens, EF-S lens | 2 Comments

Canon 70d not recognizing EF-S lens


It was a relative new 70d, in good condition. Working well with Canon EF lenses, with Tamron lenses – but NOT with two different Canon EF-S. The lenses work well with other camera. Cleaned the contacts. Nothing. Trying to rotate … Continue reading

Posted in 70d, Canon camera, EF lens, EF-S lens | 2 Comments

Broken aperture gear–EF 100mm F2,8 USM


This lens had a ERR99 problem – which, as we know, could be practically anything. Aperture didn’t worked.  I disassembled it, and I observed that the back lens element has broken collars in the barrel, so it was not possible … Continue reading

Posted in Canon lens, EF 100mm F2,8 USM | 4 Comments

Focus hunting – on Canon 17-55 F2,8 IS


On this lens I have never seen this before – but the symptom was absolutely the same like on the 17-85 lenses, so I decided to “refurbish” the USM motor. At first, You have to take it out from the … Continue reading

Posted in 17-55 F2.8 IS, Canon lens, USM | 2 Comments

“Error 01 , communication between camera and lens faulty. Clean lens contact” 


Ha-ha-ha. After cleaning the owner brings the lens to the service (to me, for example), and we repair the broken cable or whatever. I have never seen a case when cleaning helped. Till now. the lens was a simple 18-55 … Continue reading

Posted in Canon lens, General topics | 5 Comments