M7 shutter dial spacing

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boarini2003

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I've noticed that on the shutter dial on the M7, there is a little symbol between 1/30 and 1/60, which is for flash synch if I'm not mistaken. My question is, why does it take up a whole slot, whereas older models have the symbol between equally spaced speed values? It seems that the distance one must turn the dial between 30 and 60 is greater than the rest, and seems silly to me. Forgive me if the question is dumb, but I've never handled an M7.
 
Here is the specs for the M7 flash sync

"Flash synch speed
1/50 second, set automatically in the AUTO mode; slower shutter speeds can be used with manual settings; faster shutter speeds (1/250 s, 1/500 s, 1/1000 s) can be used with manual settings if the flash unit being used offers the “High Speed Synchronization” function with an SCA-3502 Adapter. "

From the Leica camera page

http://www.leica-camera.com/produkte/msystem/m7/tecdat/index_e.html
 
Because it does not select a speed mechanically. The shutter dial on mechanically timed m cameras is variable in between marked speeds with certain exceptions. M6 and later models supposedly are not, but I have yet to try one. There a speed is keyed to a lightmeter resistance value and the inbetween speeds will not work the meter properly. The shutter timing, we would have to try.

I rarely use the in between as I can`t remember the exceptions although they are in the slow ranges on early m`s. Each early m was slightly different.
 
Apart from shutter mechanics mandating a specific spread of speeds on the dial of the M2/M3/M4, there are shoe mounted light meters that couple to a cavity in that dial and which also need a fixed ratio between speeds and rotation..
 
boilerdoc2 said:
Beats me! I think you have way too much time on your hands. Kidding!

Actually I think you're right!

So the M7 has a shutter speed of 1/50? That means the speeds go from 30 to 50 to 60? That's strange, that speeds don't constantly increase by doubles.
 
boarini2003 said:
Actually I think you're right!

So the M7 has a shutter speed of 1/50? That means the speeds go from 30 to 50 to 60? That's strange, that speeds don't constantly increase by doubles.

Leica just continued the tradition of the older M6 series cameras which all have a 1/50s flash sync in the same location. They could have placed it elsewhere, like between AUTO and 4s, outside the linear shutter speed steps (like the X sync on some of Nikon's F3 and F4 pro cameras), but did not, solely due to Leica tradition. In practice, you learn to live with it, and sometimes 1/50s is useful, even if you are not using flash.
 
1/50th is the highest speed at which both curtains are totally open and therefore the highest possible electronic flash sync speed. In the normal scheme of doubling shutter speed as you turn the dial, Leica determined that 1/30th was too slow to use as a hand-held sync speed but at 1/60th the curtain width was already less than full frame. 1/50th was added to fill the gap. My guess is that other manufacturers that used focal-plane shutters had the same problem but just called 1/50th 1/60th.
 
Since we're on this subject, does anyone know why Leica hasn't 'upgraded' their flash sync to at least 1/125?
Thanx, Wright
 
Well you can do HSS (High Speed Sync) with the M7 and the pricey 54MZ series of Metz flashes and the SCA 3502 shoe, but only at 1/250, 1/500 and 1/1000s. Since this flash mode actually fires a series of small bursts from the flash, the output is very reduced, but adequate for daylight fill flash. However, you have to use manual flash (with a range readout on the flash LCD) not TTL, and manual camera shutter speeds. You can do regular TTL auto flash at or below the 1/50s normal flash sync, with full flash power. The M7 will not fire flash at 1/60 or 1/125s (just as M6 TTLS will not fire flash above the sync speed) and will only do HSS flash above those speeds.

Confusing? Well a bit arcane, to be sure, and the 54MZ flash is a bear to remember how all its functions work. The 54MZ manual dwarfs the M7's instruction booklet. It's got more complex functions built in than anyone ever uses, and an only OK user interface. But, with the M7, the 54MZ is the most advanced flash system in the M line, and is occasionally useful.
 
When I had my M2 in for CLA a while back the tech mentioned that he was able to calibrate all the speeds within close tolerances except the 1/60 which was actually 1/50, and exactly the same as the flash sync speed setting.

As to why not 1/125 for synch, that would require the horizontal-travel shutter to move more than twice as fast, and shock the Leica crowd with extra noise. >:O
 
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