Contax TLA 140 on Leica

Can Contax TLA 140 be used on Leica M (without TTL). I guess i have to put the switch to "M". Based on the guide number, i think the chart on the back tells me how far the flash can cover in M (which is the max power?). Then adjust the aperture accordingly to the distance. What I am not so sure is the M's low shutter speed of flash sync. it is only 1/50. Does it matter? The G1 is 1/100. or what if I use it on 1/200 camera that requires to set the flash on M.

I don't have leica TTL camera. If i use contax TLA 140 on a leica with TTL, will i be able to set the flash to TTL? Or this TTL only works with Contax G cameras...

Thanks.

in other word, why in flash photography, the shutter speed doesn't matter?

Because the flash provides all the light you need very quickly, but the shutter has to be fully open when the flash fires. Some focal plane shutter cameras can do that as fast as 1/250 others as slow as 1/50. You are stuck with manual on the TLA140 but other flashes with Auto may be used.

As long as you use the sync'd shutter speed or slower, the TLA 140 will work on your M. You are correct that you'd lose the TTL, because even if you had an M7 or M6TTL, the TLA 140's circuitry is not likely to be compatible. But as long as the shutter will be fully open when the flash fires, it doesn't matter.

In flash photography, the flash duration can be as short as 1/10000.... so shutter speed is irrelevant as long as the curtain is fully open when the flash pops. More important is your sync speed, and whether you want to include ambient light into your pix. Eg if you need 1s to include the ambient light, you can shoot at 1s or 2s (with some reciprocity taken into account).