M6TTL Questions

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Hello

Two questions regarding the M6 TTL. First, what is the little screw at the front of the hot shoe for? And second, what is the little,circular, rubber bump on the top-plate underneath the advance lever? Just curious.

Regards, Richard Fulco

-- Richard Fulco (calcinc@mn.rr.com), March 08, 2001

Answers

The hot shoe screw is merely a hard stop for flash mounting, ensuring the electrical contacts line up properly. The rubber bump under the advance lever is, I believe, an access point for service adjustment. John Collier could probably answer more definitively.

-- Ken Shipman (kennyshipman@aol.com), March 08, 2001.

Wait a minute. I am not qualified to answer that question! However, one of the weaknesses of the two piece advance lever is that the screw holding the plastic tip on tends to loosen and scratch the top plate of the camera. This is a very common "problem"; though I feel it adds character. I think that Leica added the rubber pad to stop the scratching of the top plate just as they added plastic bumpers at the strap lugs. I do not know for sure as I have not had the top plate off my TTL yet (lots of electronics and not recommend unless you know what you are doing which handily eliminates me) and, once again, Leica forgot to consult with me about the new design. I am starting to believe their behavior may be deliberate!!? :-)

Cheers,

-- John Collier (jbcollier@home.com), March 08, 2001.


See...John may not think he is qualified, but he can usually provide good insight anyway. I think he's more often correct than not. Thanks, John.

-- Ken Shipman (kennyshipman@aol.com), March 08, 2001.

The "rubber bump" (about 1.5mm dia. directly behind the shutter speed dial, underneath the wind lever when it is folded in), which exists on the M6 classic as well, is in reality a plastic plug that snaps into a small pilot hole. When the shutter is cocked and that plug removed, a what looks like a slotted screw head can be seen directly underneath the hole. That is in reality an eccentric cam which is the fine-tune adjustment for (simultaneously) the 1/500 and 1/1000 speeds. It should be emphasized, for those who would buy a shutter tester and do their own adjustment, that 1)it is very difficult to remove the plug without scratching the top plate; and 2)The adjuster cam sits on a movable arm with no support underneath and the cam is hard to turn, so if you bear down on the screwdriver you can bend the arm which will *not* be a good thing. I do perform this adjustment to my M6's periodically, as I've found the top speeds can drift. I use a very tiny blade to carefully and slowly pry the plug up by going all around it a little at a time, and then I grip the adjusting driver with pliers so that I can turn it without placing any downward pressure on it. It only has to move in very tiny increments, like 1/10 turn, to make a big difference in the speeds. The shutter tester I use is a handheld digital model from Calumet Photo for under $100 which is extremely accurate.

-- Jay (infinitydt@aol.com), March 09, 2001.

See, I told you so! Thanks for the info, though using pliers on a screw fitting makes this old repairman cringe. One technique to reduce the high speed drift is to set the 1/1000 speed to 1/800. There is not really much of a difference and the adjustment lasts much longer (an Erwin Putt's suggestion).

Cheers,

-- John Collier (jbcollier@home.com), March 09, 2001.



Awww...you were pretty close, John. ;-)

-- Ken Shipman (kennyshipman@aol.com), March 09, 2001.

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