1D Mark IV DOF Button...

Can some one tell me if the DOF button is supposed to move freely and have a sort of spring effect when depressed? When I push mine, it doesn't feel like the one on my Mark III and I'm wondering if there is something broke inside or if this is the way it is supposed to be.

Thanks!!

Mine is pretty solid Vince. Kinda like a longer FEL button in terms of kickback.

Mine feels about the same as my mkIII did, from memory

OK...because my Mark III has a "spring" effect to it and I was just wondering if something was wrong. I put my new 85L on the camera, stopped it down to 1.2, focused, and then hit the DOF button but nothing happened. Shouldn't I have seen some thing in the view finder though??

Isn't f1.2 the widest opening for that lens?

vinnie6756 wrote in post #12217177
OK...because my Mark III has a "spring" effect to it and I was just wondering if something was wrong. I put my new 85L on the camera, stopped it down to 1.2, focused, and then hit the DOF button but nothing happened. Shouldn't I have seen some thing in the view finder though??

It's wide open already. Pushing the DoF preview would do nothing.

OK...since I'm not to familiar with this button, I need to be at f/16 to see if this button actually works?

vinnie6756 wrote in post #12217316
OK...since I'm not to familiar with this button, I need to be at f/16 to see if this button actually works?

Nope. At f/1.4, there should be change. Whether visible / noticeable, that is the question.

Set your aperture to something other than wide open. Look into the front of the lens and push the button. If it's working, you should see the lens aperture blades closing. You'll also note the viewfinder darkening and the increased depth of field.

oldvultureface wrote in post #12217345
Set your aperture to something other than wide open. Look into the front of the lens and push the button. If it's working, you should see the lens aperture blades closing. You'll also note the viewfinder darkening and the increased depth of field.

That's what I thought!! I just put it back on and stopped it up to f/16 and after some force, I was able to get it to work. However, I actually had to put so much pressure on it, it began to hurt my finger. I have to believe it should be easier than that. I put the lens on my Mark III and tried the DOF button and it is as smooth as silk. Looks like the Mark IV is going in for repair!!

vinnie6756 wrote in post #12217450
... it began to hurt my finger...

I have three Canon bodies and none require undo pressure to stop down the lens. Definitely not normal.

Yeah...my other bodies are really smooth too!! I just checked my receipt too...purchased in January 2010!! Can't imagine how much this is going to cost to fix!!

Well since it is a POS broken camera I will buy it from you

Just give it to me and I'll take care of it without any economical hassle.

Well being a CPS gold member will help! 20% off repairs is a pretty substantial chunk of change.