Sticky Aperture?

[avarice08]

Just been to Snetterton today with my 1D mkIII and 35-350 L. Used it last weekend with no issues.

Got all set up as usual then got a Err 01 on screen.

It appears as I get over 160mm or over the widest aperture the error code appears. Also, looking through the viewfinder the blades seem to be sticking partially closed even with settings to wide open.


Any thoughts or advice?

Cheers

Rob

 

[avarice08]

No one?

 

[lensflair]

Just been to Snetterton today with my 1D mkIII and 35-350 L. Used it last weekend with no issues.

Got all set up as usual then got a Err 01 on screen.

It appears as I get over 160mm or over the widest aperture the error code appears. Also, looking through the viewfinder the blades seem to be sticking partially closed even with settings to wide open.

Any thoughts or advice?

Cheers

Rob

The aperture should stay at its widest regardless of what aperture is dialed into the camera until you press the shutter button. It should then quickly stop down just before the shutter opens.

Make sure the lens is on the body properly and maybe check the contacts are clean. Sorry can't be more help.

 

[Canon Bob]

The lens uses an electro-magnetic diaphragm unit so it would seem logical that it works or it doesn't work...ie, there's unlikely to be a failure based on focal length as such.

This probably means it's just sticking slightly closed and this becomes an issue at the longer focal lengths due to the variable aperture nature of the beast. Dust being the most likely suspect with a push/pull mechanism, I'd set it at 350mm f/22 and continuously toggle the DoF preview button to see if any foreign bodies can be shaken free.

HTH

Bob

 

[avarice08]

HI Graham,

Thanks for taking the time to reply.

I cleaned the contacts with an eraser and tried the camera on 3 bodies with same issue....

I have emailed CCR, Lehmanns and Canon for a quote to repair! Not a good week as due to be out of work at the end of this week coming!

Rob

 

[avarice08]

The lens uses an electro-magnetic diaphragm unit so it would seem logical that it works or it doesn't work...ie, there's unlikely to be a failure based on focal length as such.

This probably means it's just sticking slightly closed and this becomes an issue at the longer focal lengths due to the variable aperture nature of the beast. Dust being the most likely suspect with a push/pull mechanism, I'd set it at 350mm f/22 and continuously toggle the DoF preview button to see if any foreign bodies can be shaken free.

HTH

Bob

Thanks for the advice Bob.

I'll give your method a whirl now!


Cheers

Rob

 

[avarice08]

The lens uses an electro-magnetic diaphragm unit so it would seem logical that it works or it doesn't work...ie, there's unlikely to be a failure based on focal length as such.

This probably means it's just sticking slightly closed and this becomes an issue at the longer focal lengths due to the variable aperture nature of the beast. Dust being the most likely suspect with a push/pull mechanism, I'd set it at 350mm f/22 and continuously toggle the DoF preview button to see if any foreign bodies can be shaken free.

HTH

Bob

Cheers for this advice Bob. Have given it a whirl. No joy, but looking into the lens you can see the aperture blades starting to stick when you try this method just past the 100mm point. Up until that point the blade move in and out freely.

I would suspect you are right Bob, possibly piece of dust or something causing enough resistance, but the DoF trick couldn't dislodge it.

Worth a try though!

Thanks

Rob