M(7)ore grist for the mill

[more_money_than_brains1]

Shutter travel length has nothing to do with shutter speed; slit

width determines the exposure time on the film. However, travel

length is related to the time necessary to complete an exposure, as

to avoid distortion taking pictures of horizontally moving subjects.

 

<p>

 

Sorry Alfie, she is a BITTER CROTCH!

[ray_moth]

"A line between 125/60 to indicate the two BATTERYLESS BACKUP SHUTTER

SPEEDS. [emphasis added - more likely the ONE backup/sync speed of

1/100th - Andy]"

 

<p>

 

Since the TTL flash capabilities of the M6 TTL will probably be

retained in the M7, it would be impossible to fire the flash without

batteries, therefore there need be no link between the flash synch.

speed and the back-up mechanical speed for batteryless operation. It

has been "reported" on the LUG that the flash sych. speed of the M7

will still be 1/50 sec.

 

<p>

 

Incidentally, Olympus managed to achieve a top speed of 1/2000 sec.

for the horizontally traveling cloth shutter in its latest OM models

but the flash synch. remained at 1/60 sec.

[andy_piper2]

B.C.: actually shutter speeds are a function of slit width, as you say,

AND curtain travel speed (1mm slit traveling at 10mm/sec = 10mm slit

traveling at 100mm/sec = 1/10th sec. exposure.)

 

<p>

 

Sync speed depends in part of direction of travel - a vertical shutter

only needs a 24mm 'slit', while a horizontal shutter needs a 36mm slit,

for all of the film to be uncovered at one time. So traveling at 6000mm

per second a vertical shutter will give a 1/250th sec. sync speed but a

horizontal shutter's 36mm slit gives only a 1/166th sync speed (1/125

effectively).

 

<p>

 

Which still leaves the fact that nobody (I'm pretty sure) ever build a

regular-production horizontal-travel shutter with speeds above 1/

2000th, while vertical shutters now regularly hit 1/4000 even in entry-

level cameras. Maybe it has something to do with shutter mass and

travel speeds and braking distances and so on.

[chris_chen]

Andy,

 

<p>

 

Exactly, at least how I see it. One would need multiple slits for

higher speeds, faster overall curtain speed and/or lighter and

stronger materials (Ti or silk, how about solidified spider silk).

 

<p>

 

I wouldn't get the M7 as reported. I want the camera to fail usable

(no power) allowing the use of ALL shutter speeds.

 

<p>

 

I think the Nikon F2's shutter was purely mechanical. But somehaw I

remember that the F2 has a 1/80 only fail mode, or were all speeds

avaliable. Off topic, I know, but my F2 was stolen long ago, and

trying to remember is bugging me, so I'm asking.

[andy_piper2]

Chris: It was the F3 that had a 1/80 backup speed (fired from a

separate lever on the front) to it's auto/electronic shutter. The F2

was all-mechanical and battrey-free - not even a meter unless you used

the separate metering prisms.

 

<p>

 

Althoug oddly, the meter BATTERY went into the bottom of the camera, so

even meterless bodies had a place for a battery - sounds sort of like

the eyepiece blind in the R6.2 =8^o

[jay_.]

The F2 shutter is not powered by batteries. The F3 has the same

titanium horizontal curtains, but is electronically timed and has

AE. It has a mechanical backup speed of 1/80 triggered by a separate

release, as the main release is electromagnetic. The FE and FE2 have

electronically-timed vertical shutters with mechanical backup speeds

as do the Leica R bodies except the R8. Having owned F3's and owning

2 R7's I can say that those backup speeds are next-to-useless in

practice, except with flash. The FM3A is the first truely novel idea

to come down the pike. What a pity it is that they stopped well

short of a great camera overall: archaic, shock-sensitive meter

needle movement instead of LCD/LED; no high-eyepoint or diopter

adjustment in the finder, and no spotmeter. Leica doesn't have a

monopoly on half-baked execution. As it has been described so far, I

still plan on keeping my Hexar RF, hope perhaps to pick up a second

one for a song as some people dump theirs for an M7.

[giles_poilu]

You can't have everything. If you want AE there is a trade off -

total battery dependancy, carry lots of spares.

 

<p>

 

If you want total (virtually) reliability buy a mechanical M2/3/4/6

as we have all been doing for years.

[stefan www.randlkofer.co]

the nikon fm3a shows, that it is possible to have both

[oliver_s.]

Huh? 1/1000th top speed? The M6 will probably go out of production,

just to be reintroduced in 2005 by whoever owns the name 'Leica' then

(Leica AG will have gone bancrupt in November 2002 due to the failure

of the M7), with a few economised features that make it identical to

the current Bessa-R. I'm with Jay on the waiting list for dumped Hexar

RFs.

[dan_brown4]

Darn it! I was hoping the M7 would ditch the TTL flash circuit and

shave that 2mm off the case height. DX coding, what for?

Longer shutter release throw, are you sure that isn't a shorter

throw? Why would Leica make the excellent shutter release

worse?!? On-off switch, yikes! Is this thing made by Minolta or

Cosina? Has anyone opened the film back to see if the inards

look like a CV Bessa-R or a Nikon FM-10? I'm starting to wonder

what kind of an animal (or toy) we're looking at here.

[giles_poilu]

"..the nikon fm3a shows, that it is possible to have both.."

 

<p>

 

Yes, good point, but I don't think Leica will be doing the same with

the M.

[Robin Smith]

Very few small improvements. The on off switch is now vital since it

has an electronically controlled shutter. I am not sure that this is

worth it for timed speeds down to 4 secs. I would much rather have had

a self timer. No big deal - not worth buying over the regular M6TTL is

my thinking.

[albert_smith]

More Rumors. The same guy that Andy quoted yesterday regarding the

M7, has a new post today that may be of interest to some of you. He

says the M6 classic will be re-issued, along side the M6 TTL and M7.

 

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