M mount cameras that sync at all speeds

Assuming we're talking flash sync... actually yes, but probably not the way you want.

Electronic flash is instantaneous and usually focal plane shutters can only take advantage of it at the speeds where the shutter is fully open, so it's rare to get anything which will sync at anything higher than 1/250 (and even that's rare). But flash bulbs? They can have very long burn times, comparatively.

If you look at an M2 or M3, they both have two flash ports. One of them is for bulbs, and will sync at all speeds if you have the right bulbs. Here's a link to the manual (well, pamphlet) explaining what you can use: https://ia804603.us.archive.org/16/...ers_202112/Leica Flash Guide Numbers_text.pdf

With an M2 or M3, a CEYOO flash, and some M5, #6 or #26 "flat peak" or FP-class bulbs, you can use any shutter speed you want. As an extra special bonus, you'll also get a lot more light than you do with the average electronic flash. And you get to blind your friends! It's win/win/win.
 
hap said:
Hmmm I have a bunch of bulbs (somewhere) and the CEYOO is cheap.
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Before you jump in, be aware that:
1) the CEYOO typically comes with the cable for a IIIf or IIIg, which doesn't fit anything else (so you'll need to find the right cable to fit an M3) and
2) most bulbs you find will be M-class and typically won't sync outside of slow speeds anyway
3) information on bulbs can be difficult to find, conflicting, or even non-existent.

That said, I've been playing around with bulbs on both my IIIf and IIIg; my IIIg has a damaged flash port so I've never been able to use electronic flash on it anyway, and even with M class bulbs, I get a little bump in flash sync up to 1/60 (plus a HUGE boost in power and coverage). I'm a fan.

As an extra-special bonus, I find the light from flash bulbs does tend to look more organic and less harsh than direct electronic flash does. So while it's a bit of work (and a lot of extra expense), it does have its benefits.
 
A bit more discussion here:

Leica LTM - Rare: 50mm LTM Compur-Summicron + Compur-Summitar

I have never seen one of these and wonder why it was designed this way. Perhaps to be used a body minus a shutter? I'm not seeing a rear view but it says its a screw mount. https://www.setadelstudios.com/colle...s-only-58-made Found this article with pictures. Crazy set-up (Compur-Summitar)...
rangefinderforum.com rangefinderforum.com
 
If it only goes up to 1/200 it’s a bit of a waste of a Compur! Most went up to 1/400 or 1/500. A Prontor would have done fine, and on the whole, they stand the test of time better. I have seen a lot more stuck Compurs than Prontors.

Though I don't suppose they were thinking 50+ years into the future 😂
 
WoodallP said:
If it only goes up to 1/200 it’s a bit of a waste of a Compur! Most went up to 1/400 or 1/500. A Prontor would have done fine, and on the whole, they stand the test of time better. I have seen a lot more stuck Compurs than Prontors.

Though I don't suppose they were thinking 50+ years into the future 😂
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I wonder if the folks who made this stuff would think we (collectively) - still discussing this stuff in the first-quarter of the 21st century - need to get a life. 🤣
 
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raydm6 said:
I wonder if the folks who made this stuff would think we (collectively) - still discussing this stuff in the first-quarter of the 21st century- need to get a life. 🤣
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At least one of the leaf shutter lenses was built by Leica. I often think they put crazy things like this together so people like us _will_ talk about them. They are expert at building the myth.
 
Coldkennels said:
...
Electronic flash is instantaneous and usually focal plane shutters can only take advantage of it at the speeds where the shutter is fully open, so it's rare to get anything which will sync at anything higher than 1/250 (and even that's rare). But flash bulbs? They can have very long burn times, comparatively.

If you look at an M2 or M3, they both have two flash ports. One of them is for bulbs, and will sync at all speeds if you have the right bulbs. Here's a link to the manual (well, pamphlet) explaining what you can use: https://ia804603.us.archive.org/16/items/leica-flash-guide-numbers_202112/Leica Flash Guide Numbers_text.pdf

With an M2 or M3, a CEYOO flash, and some M5, #6 or #26 "flat peak" or FP-class bulbs, you can use any shutter speed you want. As an extra special bonus, you'll also get a lot more light than you do with the average electronic flash. And you get to blind your friends! It's win/win/win.
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While generally true information, there's more to add to this story for full understanding.

"Instantaneous" is an interesting choice of words: what is instantaneous? Both a flash bulb and an electronic flash tube have a "rise time" ... that is, the time it takes the bulb or tube to reach its rated illumination output ... and a "burn time" ... the amount of time that the reached output is maintained before it drops off below some reference threshold. They're all pretty "instantaneous" on the time scale of human perception, but the time scale of shutters and flash units is very much shorter than human perception, most of the time.

Not to get too bogged down into the details, the rise time is accommodated by the shutter mechanism by having the trigger time for flash set either long for bulbs or short for electronic flash. (This is the meaning of the M, FP, and X synchronization settings on various shutters: they all control the trigger timing of the synchronization circuit relative to the right time in the shutter operation to match different flash media.)

The burn time is generally not controlled other than by choosing the type of bulb or electronic flash unit. Typically an M class bulb has a short burn time (50-100 milliseconds) and an FP class bulb has a long burn time (100 to 500 milliseconds) ... speaking very approximately. Most consumer electronic flash units have a very short burn time ... 10-30 milliseconds max. Only big, powerful studio flash units have burn times that extend out to as much as 250-500 milliseconds, and this is why they need such huge power supplies and accumulators to operate, never mind large and rugged flash tubes that can stand the power and heat of burning for so long.

And that's why most focal plane shutter cameras have flash sync only up to a limited shutter setting, either bulb or electronic. The key is that the burn time of the flash medium has to be at least as long as the shutter curtain traversal time, typically in a film M about 20-25 milliseconds, plus the time needed for both curtains to operate to achieve a set exposure time. If the burn time from end of rise to drop off was long enough (as it might be with some FP class bulb) you could use any shutter speed. But usually it isn't so you need to set the shutter to be wide open for the entire duration of the burn time, which limits the minimum shutter time to the last setting that allows BOTH curtains to be wide open simultaneously. For horizontal traveling, 35mm focal plane shutters, this is usually between 1/30 and 1/90 second; all the ones that go up to 1/200-1/250 second are vertically traveling shutters (they don't operate any faster, they just have less distance to travel...).

(As to why these limits exist, it comes down to how much acceleration/deceleration the shutter components can stand ... there are materials limits to this which define lifespan, consistency, etc, of the shutters' operation.)

But there's a trick. :) A couple dozen years ago, given the precision of electronic shutter timing and the preponderance of vertical travel shutter mechanisms that had happened (because so many people wanted a faster X-sync shutter time), the wizards of camera and flash technology recognized that electronic flash units could be controlled differently from the simple "connect power, rise, burn" cycle, given fast enough hardware and precise timing circuitry. So control circuits were devised that allowed the flash tube to rise to a useful output spec and then be pulsed with power over a long duration in careful coordination with a very accurately timed shutter mechanism (only electronically timed and triggered shutters ... mechanical timing and control is nowhere near precise enough). With such a system, the total flash output is greatly reduced but any shutter speed can be used since the electronic flash is being pulsed to burn a long, long time (on its time scale).

Unfortunately, film Ms all have a horizontally traveling shutter with mechanical regulation .. with the possible exception of the M7, which I don't know much about other than that it has electronically timed regulation. And no dedicated electronic flash unit that I'm aware of has been designed to do this long burn simulation that would work with a Leica M.

G
 
Hexar RF and Bessas and the Zeiss ZM have vertical shutter travel and sync at 1/125. Not all that fast but faster than the horizontal travel M bodies. :)
 
splitimageview said:
Hexar RF and Bessas and the Zeiss ZM have vertical shutter travel and sync at 1/125. Not all that fast but faster than the horizontal travel M bodies. :)
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Glad I limited my comments to Leica M bodies ... I have little experience with Hexar RF or the modern Cosina Bessa models. ;)
Do any of them have electronically timed shutters? Or are they all mechanically regulated?

G
 
splitimageview said:
The Zeiss is electronic, would have to look up the others.
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I presume you mean the modern Zeiss Ikon ZM...? A friend of mine had/has one of those.

There are a number of moden M-bayonet cameras that I've heard of but have no experience with. The Rollei 35AF is another one that I've never seen except in photos.

G
 
Plenty of leaf shutter 35mm rangefinder cameras out there that can sync at all speeds. Flash sync tech on cloth shutter cameras has always been mediocre.
 
Beemermark said:
Buy a nice TLR. Not only does flash sync at all speeds but you can see the flash effect through on the fresnel screen.
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Or a Hasselblad 500CM ... then you get interchangeable lenses too. ;)
I had Rolleiflexes for years and still love them.

G
 
Interesting info. Thanks everyone. I'm committed to 35mm, I had a Rollei and using fill flash on it in the daylight was a lot of fun. I was wanting the same without leaving my Leica lens / small camera behind.
 
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