Yashica Electro 35 flash sync question

[remrf]

I know that the sync speed for the Electro 35 camera is supposed to be a 30th of a sec. when in flash mode. My question is why?

The camera has a leaf shutter supposedly sync'd at all speeds. Does this mean that one could just choose not to set the camera in flash mode and shoot with ambient settings in daylight with the flash set at a low output for fill flash shots?

I can see why when shooting indoors in dim light you could need to hang your hat so to speak on one speed to be able to determine a flash setting but why a 30th? That's a horrible speed to sync at when any speed could have been chosen such as a 125th.

Inquiring minds want to know.

 

[Wayne R. Scott]

The flash synch of 1/30th and the manual setting of 1/500 will fire the shutter in the Electro without batteries. My guess as to the flash synch of 1/30 is so that it will synch with flash bulbs. the electronic flash will synch at any speed.

Wayne

 

[ErnestoJL]

AFAIK, and perhaps I´m wrong, if no batteries, the selector ring (B-Auto-Flash) is not operative, as it´s an electronic switch inside the lens barrel. It is, it doesn´t have any mechanical function, then if no batteries, the shutter fires allways at it´s default speed (1/500).

The reason why the synch speed is so low is that at the time te YE35 was released, both M bulbs and electronic flash units existed, so the camera should synch with both. The original manual shows an YE35 fitted only with a bulb flash unit instead of an electronic unit (1966).

The design of the shutters of the time included a mechanical switch to select it at any speed (allways leaf shutters). The electronic shutter may have posed several new problems so a simple and elegant solution was chosen: a slow synch speed, this time 1/30th.

It´s interesting to note that a close descendant of the YE35, the MG 1 has a switch to select (electronically) a fixed 1/100th which is much more comfortable than 1/30.

Besides, if you do not select a fixed speed the camera will synch, but at a speed that may be as long as 30 full secs!

 

[X360]

what do you guys mean by sync?

My observation is that in flash mode, the flash pics come out pretty well exposed.
If I leave it in auto and use the flash I get effects that look like the subject is frozen but everything else has motion blur. Is that when the flash is not synched?

 

[ErnestoJL]

If you set flash mode, the shutter fires at 1/30, but in auto the meter selects the speed which can go from 1/500th to >30 fullsec.
So, if the metered auto exposure is 1 sec (flash mode isn´t set), and you use a flash unit, the flash will fire at the beginning of that period, but the shutter will remain open for a full sec.
Then something in the picture will be motion blurred.

Ernesto

 

[kaiyen]

Flash sync is the highest shutter speed at which the entire shutter is open for the flash to be exposed. With curtain shutters, there are blades or just a single curtain that flies across the film gate when you hit the shutter release. Not all of the film frame is exposed at the same time - the curtain is sliding across. But a flash burst occurs so quickly that you need the entire film frame exposed. So, for instance, on a Leica I think a shutter speed of 1/30 is the fastest you can get and still have the frame properly exposed re: the flash.

What you're seeing when the subject is frozen but everything else is blurry is simply a slow shutter combined with flash. You can go _slower_ than the sync speed, just not faster.

allan

 

[remrf]

Flash sync is the highest shutter speed at which the entire shutter is open for the flash to be exposed. With curtain shutters, there are blades or just a single curtain that flies across the film gate when you hit the shutter release. Not all of the film frame is exposed at the same time - the curtain is sliding across. But a flash burst occurs so quickly that you need the entire film frame exposed. So, for instance, on a Leica I think a shutter speed of 1/30 is the fastest you can get and still have the frame properly exposed re: the flash.

What you're seeing when the subject is frozen but everything else is blurry is simply a slow shutter combined with flash. You can go _slower_ than the sync speed, just not faster.

allan

What you say is true for the Leica which has a focal plane horozontal curtain shutter. But the Yashica has a copal leaf shutter which means that all speeds are in "sync"( I.E. the flash is triggered at the full open position of the shutter no matter what the speed.).The motion blur refered to in an earlier post would have to have been when the auto shutter selected a speed longer than a 30th. Sync speed has always been a problem with the focal plane shutter and it wasn't until much more recent slr's or rf's that you could get an fp shutter with a 125th sync speed. My Minolta x-700's and my Mamiya 645 all have fp shutters and all have a sync speed of a 60th. My leica IIIa being one of the early cameras to have strobe sync has a sync of a 30th which really blows if you are trying to use fill flash in daylight.

Which was why I asked the original question. One answer was that the position was intended for flash bulb which may be true. However the icon on the camera indicating flash mode is an electric arch, not a flash bulb so I have to wonder. Strobes had been available for quite a few years when the Electro series was introduced.

 

[erikhaugsby]

So, for instance, on a Leica I think a shutter speed of 1/30 is the fastest you can get and still have the frame properly exposed re: the flash.
allan

On a M* Leica, the Flash-Sync speed is 1/50th sec. There is a convinent little red 'Lightining Bolt' symbol between the 30 and 60 positions to indicate the Flash speed.

Granted, this thread is concerned with the Electro 35.
ohwell

 

[ErnestoJL]

M flash bulbs required some early trigger to get full illumination because their light vs. time curve is one of slow rise and fast decay.

Then it was needed either a slow shutter speed (to provide the shutter remains open for the time the lamp burns), or some kind of mechanical device that ingnites the flash bulb when the shutter starts to open, not when it´s fully open. The simplest solution for this in the YE35 was to choose a fixed low speed for both flash types, thus avoiding mechanical complications.

Electronic flash units work in a different way, and lighting is almost constant for the entire duration of the discharge of a capacitor inside a gas filled tube (which is very short, being the longest times about 1/800th in very old units).
This way leaf shutters can synchronize even at 1/500th or higher speeds, just because the light exists for a shorter time than that of the shutter fully open.

For this same reason, FP shutters usually have low synch speeds (from 1/30 to 1/60 in old cameras and newer types up to 1/250).
In ancient times, there were a special type of flash bulbs which were called FP lamps.
This lamps allowed to shoot FP shutters up to their max speed, because their burning time was much longer than 1/30th sec.

Fill flash deserves (IMO) some tests before being sure how to do it, but I guess that you can shoot in AUTO without troubles if ambient light is enough to allow the camera to fire at >1/60th sec, and you use an Auto flash. Any non Auto flash unit would need a lot of calculations.

Ernesto