645 135mm LS shutter

**Chuckie** · 02-18-2014, 02:57 AM

Hi there, I hope someone can help.

I bought some 645 kit and I've been testing it and there seems to be an issue with the leaf shutter on the 135mm LS lens. Mounted on the 645n with the LS dial set on 0 it works normally, i.e. as I change the aperture the shutter speed changes and there don't seem to be any problems there. When I change the LS dial to one of the settings, the 645n shows LS as it should, but I can still see through the viewfinder. The lens manual is not clear on this but to me it says that the shutter is already cocked, and the shutter cocking ring also moves easily in either direction. Is there any way to manually un-cock the leaf shutter to check if it is faulty or do I have to take a picture to un-cock it. The lens manual mentions activating the DoF lever to do this but it hasn't worked.

If I have a dud leaf shutter I am not worried as I have a nice portrait lens, but I would like to be able to use the leaf shutter if I can. I got the kit for a very good price and everything is in good condition so I am not going to worry about asking the seller for a refund.

-Linus- · 02-18-2014, 05:03 AM

It is cocked when you can see through the lens. When you pull the lever (red dot at 12:00, lever at 3:00) the iris should start to move to the corresponding f-value and then should close the leaf shutter.

**Chuckie** · 02-18-2014, 11:21 PM

Originally posted by -Linus-

It is cocked when you can see through the lens. When you pull the lever (red dot at 12:00, lever at 3:00) the iris should start to move to the corresponding f-value and then should close the leaf shutter.

Thanks! I'll give it a try. That seems to confirm that stopping down the lens should close the leaf shutter.

It worked! I find on my one I have to manually return the cocking ring to its original position before taking the shot and then the leaf shutter closes after. I tested all the speeds and it definitely speeds up going from 60 to 500 so it looks like I have a fully functioning lens.

02-18-2014, 02:57 AM	#1
Chuckie Site Supporter Join Date: Nov 2010 Location: Douglas Photos: Albums Posts: 168	645 135mm LS shutter Hi there, I hope someone can help. I bought some 645 kit and I've been testing it and there seems to be an issue with the leaf shutter on the 135mm LS lens. Mounted on the 645n with the LS dial set on 0 it works normally, i.e. as I change the aperture the shutter speed changes and there don't seem to be any problems there. When I change the LS dial to one of the settings, the 645n shows LS as it should, but I can still see through the viewfinder. The lens manual is not clear on this but to me it says that the shutter is already cocked, and the shutter cocking ring also moves easily in either direction. Is there any way to manually un-cock the leaf shutter to check if it is faulty or do I have to take a picture to un-cock it. The lens manual mentions activating the DoF lever to do this but it hasn't worked. If I have a dud leaf shutter I am not worried as I have a nice portrait lens, but I would like to be able to use the leaf shutter if I can. I got the kit for a very good price and everything is in good condition so I am not going to worry about asking the seller for a refund.

02-18-2014, 11:21 PM	#3
Chuckie Site Supporter Join Date: Nov 2010 Location: Douglas Photos: Albums Posts: 168 Original Poster	Originally posted by -Linus- It is cocked when you can see through the lens. When you pull the lever (red dot at 12:00, lever at 3:00) the iris should start to move to the corresponding f-value and then should close the leaf shutter. Thanks! I'll give it a try. That seems to confirm that stopping down the lens should close the leaf shutter. It worked! I find on my one I have to manually return the cocking ring to its original position before taking the shot and then the leaf shutter closes after. I tested all the speeds and it definitely speeds up going from 60 to 500 so it looks like I have a fully functioning lens. Last edited by Chuckie; 02-20-2014 at 11:22 PM.

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02-18-2014, 05:03 AM	#2
-Linus- Senior Member Join Date: Dec 2009 Location: Münsterland Posts: 139	It is cocked when you can see through the lens. When you pull the lever (red dot at 12:00, lever at 3:00) the iris should start to move to the corresponding f-value and then should close the leaf shutter.