Any comments about this one?
Bronica ETR and Zenzanon 45-90/4-5.6 PE and Zenzanon 75/2.8 MC. Problem: blank unexposed frames in the roll. Both lenses operates pretty much the same: shutter doesn't open always when firing. Both lenses works "fine" until I touch the focal length and/or focus ring. That most likely kills them both. Zoom perfoms a little better than the prime. Battery is new silver oxide. Tested with three different backs. Zoom lens looks like a brand new. After four days of testing, at least the zoom lens works better and better every time.
So, are the lenses in a need of lubrication? Body? Flex cables? Solenoid magnets? Body works fine, mirror is rising etc.
Here's few videos about the problem:
Here I test the zoom lens mechanics with hands: https://www.dropbox.com/s/y2x9ds50jmzpws3/Zenzanon_45-90_mechanics_operated_by_hands.MOV?dl=0
Here I test the zoom lens and it is shown how it dies immediately after I change the focal length and focus: https://www.dropbox.com/s/juyx1fcz8rdnbbc/broniza_zoom_lens.mp4?dl=0
Similar video about 75mm lens, acting weird: https://www.dropbox.com/s/pl68chh4oehjxax/Zenzanon_75mm_acting_weird.MOV?dl=0
One more video, filmed from back: https://www.dropbox.com/s/24geo3uh721v8cv/From the back.MOV?dl=0
Bronica ETR and Zenzanon 45-90/4-5.6 PE and Zenzanon 75/2.8 MC. Problem: blank unexposed frames in the roll. Both lenses operates pretty much the same: shutter doesn't open always when firing. Both lenses works "fine" until I touch the focal length and/or focus ring. That most likely kills them both. Zoom perfoms a little better than the prime. Battery is new silver oxide. Tested with three different backs. Zoom lens looks like a brand new. After four days of testing, at least the zoom lens works better and better every time.
So, are the lenses in a need of lubrication? Body? Flex cables? Solenoid magnets? Body works fine, mirror is rising etc.
Here's few videos about the problem:
Here I test the zoom lens mechanics with hands: https://www.dropbox.com/s/y2x9ds50jmzpws3/Zenzanon_45-90_mechanics_operated_by_hands.MOV?dl=0
Here I test the zoom lens and it is shown how it dies immediately after I change the focal length and focus: https://www.dropbox.com/s/juyx1fcz8rdnbbc/broniza_zoom_lens.mp4?dl=0
Similar video about 75mm lens, acting weird: https://www.dropbox.com/s/pl68chh4oehjxax/Zenzanon_75mm_acting_weird.MOV?dl=0
One more video, filmed from back: https://www.dropbox.com/s/24geo3uh721v8cv/From the back.MOV?dl=0