I have a mint 1.4 lens, the iris works, but in a weird way. It is a new style lens, does not have the usual single push button that allows the breechlock to open and close, it has a couple of little holes with a thin straight piece of metal coming up. When I put the cap on, I cannot use the iris on the barrel BUT I can twist it on the letus and it will open and close (weird, yes). It doesn't so much snap to the different iris settings so much as open and close smoothly without stopping. So it works, I just have to find a way to get it to work on my letus properly. Any experience?

hey dave.. i didnt know you had a letus... i wonder how many people in canada have one of these,, or another mini35 alt. I believe im probably the only one here in NB.... im in halifax as of this weekend for the next 6 months.. and i dont know if anyone here has one either.

back to your prob.. are you able to post a pic somewhere of the backside of lens? Is it an fd or a different style?

I thought with most newer lenses the iris was controlled by the camera body. It's my understanding that on the adapters the newer lenses stayed open at their widest aperture. I could be wrong.

No, I can change the aperature on it, just not the way I want to - ie; on the barrel. I will keep playing with it and see what happens.

Andrew, the Letus is not mine - it is a friends that I am borrowing for a while.

I have a same/similar lens, the newer canon fd lenses dont have the metal piece that clicks into place, but if you wedge it into place it will have the same effect. I just cut a little rectangular piece of hard plastic pushed the metal piece into place (the opposite position from its resting position) and wedged in the plastic piece to keep it there. Then the iris will be operable just like in the older metal canon lenses. I assume this is the same issue you are having. I hope this helps.

Piece of plastic did it! Thank Noah!