40-150 f/2.8 Detaching from E-M1

Discussion in 'Olympus Cameras' started by db96, Apr 19, 2015.

  1. db96

    db96 Mu-43 Regular

    145
    Jun 10, 2012
    Central Indiana
    Had a great morning at the zoo yesterday shooting with my E-M1 and 40-150 f/2.8. Took some great shots but had one very scary problem. At least 4 times, I looked down and my lens had come loose from the camera. Luckily it only came totally unattached once and I was holding the lens and the camera was swinging on my neck strap. At first I though I had hit the release button, but I had it come loose again when I was consciously avoiding it.

    The button and "click" feel normal, but I suppose there is the possibility of a faulty lens release button when using the heavier lens. Anyone else have this problem? What should I do to prevent lens disaster?
     
  2. Brian Beezley

    Brian Beezley Mu-43 All-Pro

    Take a look at the metal pin on the camera mount and the recessed dimple on the lens mount. If either is worn, that might be the cause.

    I modified an extension tube to tighten a very loose fit. I cut out a circular ring from a AAA auto club sticker and attached it to the extension tube mount to slightly thicken it. This should not affect lens operation as long as it can focus slightly beyond infinity. This modification doesn't address the cause of your problem, but it may prevent the lens from detaching completely if the pin comes out of the dimple.

    Brian
     
  3. b_rubenstein

    b_rubenstein Mu-43 All-Pro

    Mar 20, 2012
    Melbourne, FL
    The pin in the camera body is probably not fully extending into the lens. I would suggest that when you mount the lens, rotate it back and forth a little to make sure the pin fully engages the lens. I just checked the engagement hole in the lens of a few Olympus lenses, and not all of the have a chamfer around the edge of the hole (12-40/2.8). The chamfer guides the pin into the hole even if the alignment is a little off.
     
  4. eteless

    eteless Mu-43 All-Pro

    Jun 20, 2014
    The E-M1 has an electronic disengage, if the pin is not fully extended the body will not power the lens mount to prevent short circuits (and EVF will disable). There is a small amount of tolerance on the extension (Off the top of my head one of my bodies disabled if it didn't extend more than 1.5mm but the others were 1.2mm with the full length being 2mm - the 1.5mm one did not work with the first metabones EF-m4/3 speedbooster until a refined mount was made. My equipment is currently in travel cases as I just got back from overseas yesterday so I can't check at this time).

    Depending on how your strap is mounting it may be looping around the front of the camera and depressing the button, as the lens mount is not all that stiff it doesn't take much to get it moving. I would not suggest thickening the lens mount with a sticker as while it will increase the resistance required it will also impair the 'weatherproof' seal, you want both the rubber gasket and bayonet flange to be clean/flat to provide a good mating surface. If it were a problem for me and I were to modify the setup somehow I would put a lip/rise using Suguru around the release button so that I had to depress it below the level of the surround (so it were protected and not exposed).