Help! Lens stuck on camera!!!

[TME]

Hi,

Was just using the 7D with a Sigma 17-35mm and a 100-400mm... swapping lenses all night... suddenly my 17-35mm got stuck. The view through the viefinder is extremely dim. Looks like the DOF preview got stuck... I remember pressing the DOF preview button while shifting into position... then my camera went dead... after I remove the batteries and put them back, the camera came back ot live but the view dimmed and the lens got stuck. Any remedies? I tried rotating the lens and remove it but it got stuck halfway. And I tried using greater force and it still won't duge. I think the lever on the camera body slipped past the aperture lever in the lens. How?! Looks like must send back to KM service centre unless someone has a better solution! Anyone has such an experience before and rectified it? Thanks!

[deslim27]

looks like you are right, the aperture level is stuck. if possible, let KM technician do it for you, at least they cannot blame you for mishandling if the level break after they force it out.. kekeke.

[fastshot]

I think you better bring the whole thing back to KM service centre.

I don't have a solution for you, but I recently took a very close look at the whole thing because of a lens sticky aperture (sticky at full open). The aperture tab on the camera is connected to an aperture control ring just behind the lens mount. This ring has tooth gears around the rim. Maybe the aperture control ring was somehow forced out of position. The aperture tab contacts the lens aperture tab at the thin edge - only about 1mm wide. But I think the tabs won't slip pass each other unless the lens wasn't sitting flush on the body before you turn the lens.

Hopefully it won't be a costly repair.

[TME]

Originally Posted by fastshot I think you better bring the whole thing back to KM service centre. I don't have a solution for you, but I recently took a very close look at the whole thing because of a lens sticky aperture (sticky at full open). The aperture tab on the camera is connected to an aperture control ring just behind the lens mount. This ring has tooth gears around the rim. Maybe the aperture control ring was somehow forced out of position. The aperture tab contacts the lens aperture tab at the thin edge - only about 1mm wide. But I think the tabs won't slip pass each other unless the lens wasn't sitting flush on the body before you turn the lens. Hopefully it won't be a costly repair.

Thing is I was taking shots all along... about 20-30 shots after I swapped lenses... and I was not shooting wide open... the max aperture was f/2.8 and I was shooting half-stop down at f/3.5 or f/4. So the aperture tab was actuated in every shot that I took prior to the malfunction. Therefore it cannot be that the lens was not flush when I mounted the lens. Anyway can u even mount the lens if it is not flush?

Perhaps u are right in the other point... the aperture control ring got jarred out of position but am not sure why that should happen anyway...

Haiz... the camera is still under warranty. I bought it this year. Really sianz.... Anyway, where is the service centre now?

[sulhan]

Originally Posted by TME Hi, Was just using the 7D with a Sigma 17-35mm and a 100-400mm... swapping lenses all night... suddenly my 17-35mm got stuck. The view through the viefinder is extremely dim. Looks like the DOF preview got stuck... I remember pressing the DOF preview button while shifting into position... then my camera went dead... after I remove the batteries and put them back, the camera came back ot live but the view dimmed and the lens got stuck. Any remedies? I tried rotating the lens and remove it but it got stuck halfway. And I tried using greater force and it still won't duge. I think the lever on the camera body slipped past the aperture lever in the lens. How?! Looks like must send back to KM service centre unless someone has a better solution! Anyone has such an experience before and rectified it? Thanks!

Hi TME,

I have personally experience this previously...long time back with a sigma 70-300mm APO Macro Super...I was taking the shot and tried to zoom and then the problem occured on my DYnax 7.

The Problwm was as follows (the one that most likely you are facing now).


I came back home ...ad did the following - which apparently freed the lens.
Carefully i played around with the lens ZOOM in and out as i press the lens release button.
Caerefully repeat the lens removal action as i press the lens release button too.
The lens eventualy came out at the tele end.

I tear apart the lens and found the problem to be the one as described above. The inner end of the lens bar actually got disengaged due to a slight flex otuwards form the "C" feature which stays in contact with the aperture as the lens moves througout the zoom position.

The Problem will occur at the longest zoom positon whee the lens extends and the "C" feature is held towards the end of the bar. So if the bar has a flex outwards character(due to part tolerances) the Actualtor bar will slip out easily.

Try the above method first to free the lens at the tele end.

if cannot, bring to KM. They would probabably do a fornt element extraction method... else...they need to saw the lens off....juz kidding...

rgds,
sulhan

[TME]

One more point... pressing the DOF preview button now gives a short "shicck" sound instead of the usual sound (can't remember what it is but not so short sounding)... like the aperture lever on the camera is hitting thin air...

[TME]

Originally Posted by sulhan Hi TME, I have personally experience this previously...long time back with a sigma 70-300mm APO Macro Super...I was taking the shot and tried to zoom and then the problem occured on my DYnax 7. The Problwm was as follows (the one that most likely you are facing now). I came back home ...ad did the following - which apparently freed the lens. Carefully i played around with the lens ZOOM in and out as i press the lens release button. Caerefully repeat the lens removal action as i press the lens release button too. The lens eventualy came out at the tele end. I tear apart the lens and found the problem to be the one as described above. The inner end of the lens bar actually got disengaged due to a slight flex otuwards form the "C" feature which stays in contact with the aperture as the lens moves througout the zoom position. The Problem will occur at the longest zoom positon whee the lens extends and the "C" feature is held towards the end of the bar. So if the bar has a flex outwards character(due to part tolerances) the Actualtor bar will slip out easily. Try the above method first to free the lens at the tele end. if cannot, bring to KM. They would probabably do a fornt element extraction method... else...they need to saw the lens off....juz kidding... rgds, sulhan

Sulhan thanks but this is not the same as my problem... my zoom ring and focus rings move smoothly with the camera on or off. It seems to be a purely aperture lever problem. It seems that the aperture lever on the camera is obstructing the movement of the lens along the lens mount... that seems to suggest that the aperture lever on the lens slipped past the camera's lever. So when I rotate the lens, the lens' aperture lever hits the camera's aperture lever and moves until it hits the stop on the lens mount. And therefore the lens cannot rotate further and then I can't take out the lens... I expect that they would have to either dismantle the lens or the camera, although I have absolutely no idea how u can dismantle the lens from the front since there does not seem to have any access points. I notice two screws on the front of the camera body though, just above the lens on either side. That may allow u to lift the entire lens mount out... anyway I'll be sending it down lar.... so sad...


Or as fastshot mentioned, somehow the aperture control ring got knocked out of alignment... and so the the aperture lever on the camera jammed, leaving the lens permanently stopped down... but that would probably mean that the lens cannot rotate at all in the lens mount. But mine can rotate almost all the way out...

[Drudkh]

oh man, sorry to hear that. hope you can safely remove the lens.

yes, the aperture levers, both on the camera and the lens went pass each other when you mount the lens but did not bend the levers. that's why you can't remove the lens cause now they are hitting each other.

[Drudkh]

TME, have you tried removing the lens while pressing and hold the DOF button while the camera is on?

[sulhan]

Originally Posted by TME Sulhan thanks but this is not the same as my problem... my zoom ring and focus rings move smoothly with the camera on or off. It seems to be a purely aperture lever problem. It seems that the aperture lever on the camera is obstructing the movement of the lens along the lens mount... that seems to suggest that the aperture lever on the lens slipped past the camera's lever. So when I rotate the lens, the lens' aperture lever hits the camera's aperture lever and moves until it hits the stop on the lens mount. And therefore the lens cannot rotate further and then I can't take out the lens... I expect that they would have to either dismantle the lens or the camera, although I have absolutely no idea how u can dismantle the lens from the front since there does not seem to have any access points. I notice two screws on the front of the camera body though, just above the lens on either side. That may allow u to lift the entire lens mount out... anyway I'll be sending it down lar.... so sad... Or as fastshot mentioned, somehow the aperture control ring got knocked out of alignment... and so the the aperture lever on the camera jammed, leaving the lens permanently stopped down... but that would probably mean that the lens cannot rotate at all in the lens mount. But mine can rotate almost all the way out...

Hi TME,

The example above was for the sigma lens. For the km one....i juz checked
The Aperture actuator actually is a long bar that maintain the aperture - In this lens they used a pin instead of a "c catch".

As the aperture is spring loaded to be always closed (stopped down) this mean that your actuator catch could either be dislodged . The aperture assembly does not move together with any of the group. So can't solve like i did for the sigma lens mentioned above..

Send to KM....since it s still under warranty...

rgds,
sulhan

[TME]

Originally Posted by Drudkh TME, have you tried removing the lens while pressing and hold the DOF button while the camera is on?

Yeah tried a combination of DOF button only, DOF + lens release catch, lens release catch only, plus other permutations pressing the DOF continuously, etc... no use leh... haiz...

[TME]

Originally Posted by sulhan Hi TME, The example above was for the sigma lens. For the km one....i juz checked The Aperture actuator actually is a long bar that maintain the aperture - In this lens they used a pin instead of a "c catch". As the aperture is spring loaded to be always closed (stopped down) this mean that your actuator catch could either be dislodged . The aperture assembly does not move together with any of the group. So can't solve like i did for the sigma lens mentioned above.. Send to KM....since it s still under warranty... rgds, sulhan

Im using the Sigma 17-35mm... it's a bar like your Sigma lens.

[TME]

Sent in for repair. Should get it by end of Sep. Apparently no need to pay if the camera is not damaged.... not sure if they would compensate for the lens damage (if any) and if it was caused by the camera... just crossing my fingers and hope nothing is damaged...

[TME]

Got the camera back but it's been sent in again...

The lens was stuck cos the len mount on the camera malfunctioned. So it was replaced... no problems there...

While waiting for the bill, I talked to Seah and asked him to let me try the 11-18mm.. I took a few shots (A mode, no flash at ISO400, sRGB Natural+) and noticed that the camera underexposed badly... also the shot looked very blue... I told him and he tried with the same results even after resetting the camera... anyway he picked up the display 7D and lo and behold it exposed properly... after a few more rounds of testing, we found that my body underexposed consistently by 1 stop... heck... he suspects it might be a faulty contact on the replaced lens mount... anyway camera is back in ICU for a minimum of a week... btw the results are repeated for Sigma 17-35mm, KM 18-200mm and KM 11-18mm... initially thought it was the DT lenses but turn out it is not...

Not sure if it is my camera or the lens mount issue or inherent to a certain batch of 7D... any bros with similar issues... hope I can get it back next week but I may have to wait until mid Oct...

[Drudkh]

Wow... that's bad!
My cam will only underexpose if undershade or indoor. outdoors under the sun has spot on exposure.

[TME]

Originally Posted by Drudkh Wow... that's bad! My cam will only underexpose if undershade or indoor. outdoors under the sun has spot on exposure.

I was shooting indoors with the tech in the service centre... taking shots of the office with the 11-18mm... it was underexposing by 1 stop consistently while the display camera had spot on exposure... looks like yours might have the same problem...

[Drudkh]

Originally Posted by TME I was shooting indoors with the tech in the service centre... taking shots of the office with the 11-18mm... it was underexposing by 1 stop consistently while the display camera had spot on exposure... looks like yours might have the same problem...

hmmm, so far still can tahan lor, can't live without no 7D on weekends. haha.. Will see how's your cam first before I send mine in.

[TME]

Originally Posted by Drudkh hmmm, so far still can tahan lor, can't live without no 7D on weekends. haha.. Will see how's your cam first before I send mine in.

Hope I can get it back by 6 Oct...

[Drudkh]

Good luck to your cam!

[UY79]

Another case.
http://forums.dpreview.com/forums/re...ssage=15143167