I have a Zuiko 21/3.5 & 200/4 with a Fotodiox adapter to use on my 1D MkII and 40D.
What controls or stops down the aperture when the shutter is activated? I see the lenses have a manual stop down button on the side. If I stop the lens down with just the aperture ring it does not seem to close the blades unless the button is pushed.
I get the same metering wide open as at f/16. Something not working right.
User error?

Thanks,
JayT

Sirfishalot wrote:
I have a Zuiko 21/3.5 & 200/4 with a Fotodiox adapter to use on my 1D MkII and 40D.
What controls or stops down the aperture when the shutter is activated?

Usually there is a tab on the adaptor ring that engages with the stop-down lever on the lens. If you attach the adaptor to the lens without attaching to a body you should be able to see the tab engage, or you should be able to test the lever manually. Some shooters actually remove the stop down tab, preferring to focus wide open and then quickly stop down with the DOF preview button on the lens, but afaik the fotodiox adaptors have it there as stock.

olyacme wrote:

Usually there is a tab on the adaptor ring that engages with the stop-down lever on the lens. If you attach the adaptor to the lens without attaching to a body you should be able to see the tab engage, or you should be able to test the lever manually. Some shooters actually remove the stop down tab, preferring to focus wide open and then quickly stop down with the DOF preview button on the lens, but afaik the fotodiox adaptors have it there as stock.

Oh crap,
It doesn't look like the cheaper Fotodiox adapters have such a tab. So I've just been shooting wide open all this time.

JayT

Sirfishalot wrote:
Oh crap,
It doesn't look like the cheaper Fotodiox adapters have such a tab. So I've just been shooting wide open all this time.


Hmm, it appears to be there; in the three / nine o'clock positions in this photo:

-Or your aperture mechanism could be defective.

-Or your blades could be stuck.


Can you see the blades adjust if you hold the lens, sans adapter, pinch the aperture-flanges, and turn the ring? I assume yes, from your OP, but just checking.

olyacme wrote:
Sirfishalot wrote:
Oh crap,
It doesn't look like the cheaper Fotodiox adapters have such a tab. So I've just been shooting wide open all this time.


Hmm, it appears to be there; in the three / nine o'clock positions in this photo:

Jay,

I've never had any difficulty with the Consumer Fotodiox adapters on my Zuikos, and I have a bag full of them. Sometimes the adapters are very tight and don't twist fully to engage the aperture tab. Make sure you hear the lens "Click" into place. When you have the tab properly engaged, you'll see that's moved about half way across the space -

davidearls wrote:
Jay,

I've never had any difficulty with the Consumer Fotodiox adapters on my Zuikos, and I have a bag full of them. Sometimes the adapters are very tight and don't twist fully to engage the aperture tab. Make sure you hear the lens "Click" into place. When you have the tab properly engaged, you'll see that's moved about half way across the space -

David,
Thanks, but for some reason my adapter doesn't have the tab to engage. I can hear the click stop on my 200/4, but not on my 21/3.5. In either case there doesn't appear to be anything on the adapter to engage the aperture lever on the lens.

JayT

That's the way I prefer to use mine (like a preset lens) so if you don't want it...

cogitech wrote:
That's the way I prefer to use mine (like a preset lens) so if you don't want it...
Paul,
Are you saying that you have to hold down the lens preview button while also pressing the shutter release? 2 finger or 2 hand operation?
Potodiox is telling me the adapter does not come with the tab even though it on their product image.

Thanks,
JayT

Every adapter should come with the pin installed. (it is a pin, not a tab, after all. In fact, it is a tiny bolt).

And, yes, I hold down the DOF preview button just before releasing the shutter. My left hand is right there on the lens anyway. My thumb and pointing finger do the focus and my middle finger sits poised and ready to press the DOF button just before metering and releasing the shutter.

It is about as "automatic" as stop-down metering gets. I wish all my manual lenses had this ability.

For tripod work, I just use an adapter with the pin installed.

If Photodiox is not willing to work with you on this, send it back and never buy from them again. They are idiots if they are selling these adapters without an aperture-engage pin. Whether you decide to unscrew the pin and use my method should be up to you, not them.

Paul,
Sorry if I'm not quite following you; so the Zuiko DOF preview must be held down while the shutter is tripped? I could've swore I tried to do this on my MkII and got an error message. I'll confirm when I'm home tonight.

Either way it seems the Photodiox is not clear about this on their website. The product image clearly shows the pin and yet someone from there has wrote to me that the adapter doesn't come with the pin. That would make it useless for tripod work wouldn't it?

Thanks,
JayT

Sirfishalot wrote:
Paul,
Sorry if I'm not quite following you; so the Zuiko DOF preview must be held down while the shutter is tripped? I could've swore I tried to do this on my MkII and got an error message. I'll confirm when I'm home tonight.


Yes, the DOF preview button is basically another route to doing what the body would do with the stop-down lever. If the lever is not forced over by a tab on the adaptor, and no cam within the camera is going to automatically actuate it, you must press and hold down the DOF preview button to stop the lens down manually before firing the shutter (or metering). As far as your body is concerned, it is simply seeing less light and will meter accordingly.

Sirfishalot wrote:
Either way it seems the Photodiox is not clear about this on their website. The product image clearly shows the pin and yet someone from there has wrote to me that the adapter doesn't come with the pin. That would make it useless for tripod work wouldn't it?


Being of momentary action, the DOF preview stopdown method is a major pain to use in combination with a tripod. Most people who shoot freehand with a tab-less adaptor keep a tabbed one around for tripod use as well.