What limits Shutter Sync?

I understand what it is and how its supposed to work, but I can't understand how very old cameras could sync at 1/500 and nowadays we have 1/250 (5D2) and 1/200 (5D3).
Is that a shutter characteristic? Or is it just limited by the manufacturer as to sepparate it from their pro lineup?
Thank you in advance!

Alex_Venom wrote in post #15405891
I understand what it is and how its supposed to work, but I can't understand how very old cameras could sync at 1/500 and nowadays we have 1/250 (5D2) and 1/200 (5D3).
Is that a shutter characteristic? Or is it just limited by the manufacturer as to sepparate it from their pro lineup?
Thank you in advance!

All explained on Wikipedia.

Alex_Venom wrote in post #15405891
I understand what it is and how its supposed to work, but I can't understand how very old cameras could sync at 1/500 and nowadays we have 1/250 (5D2) and 1/200 (5D3).
Is that a shutter characteristic? Or is it just limited by the manufacturer as to sepparate it from their pro lineup?
Thank you in advance!

When I need faster sync speed I reach for my in the lens shutter cameras - Phase One MFDSLR and others over any focal plane camera.
Its not a real issue unless you mix amble ambient since the flash duration is the effective shutter speed.

Different types of shutters behaves differently.

But the type of shutters we have in modern cameras needs to be very exact. And have a long life. A digital sensor can't survive that the shutter was slightly slower than normal. That would completely blow highlights. We want 10 exposures after each other to be repeatable. So travel speed must be repeatable. And timing between the two curtains must be repeatable.

A curtain shutter only open fully for slow exposures. For fast exposures, the upper and lower curtain moves at the same time. So you only expose a narrow portion of the sensor at a time as you have a narrow slit move over the sensor. So at 1/1000, the time that narrow slit glides past a specific part of the sensor takes 1 millisecond. But the full movement time of the curtains is longer.

And since the flash have a very short light time, the flash light would only light up a small part of the sensor. If going 1/4000 instead, an even smaller part of the sensor would be open to light when your flash unit flashes.

So the flash sync time relates to exposures long enough that one curtain have opened fully, having the full sensor accumulating light, before the second curtain starts to move to hide the sensor again.

The nice thing with a curtain shutter is that it allows extremely short shutter times with limited movement speed of the curtains. It is only the precision you can move the curtains with that controls the shortest shutter time.

It is possible to create a curtain shutter to allow faster travel. But it will affect the life time of the shutter. You really need to have extreme travel speeds to fully open one curtain before closing the second curtain if you want faster sync times.

^^^^

Thank you. Very interesting.

pwm2 wrote in post #15405957
Different types of shutters behaves differently.

But the type of shutters we have in modern cameras needs to be very exact. And have a long life. A digital sensor can't survive that the shutter was slightly slower than normal. That would completely blow highlights. We want 10 exposures after each other to be repeatable. So travel speed must be repeatable. And timing between the two curtains must be repeatable.

A curtain shutter only open fully for slow exposures. For fast exposures, the upper and lower curtain moves at the same time. So you only expose a narrow portion of the sensor at a time as you have a narrow slit move over the sensor. So at 1/1000, the time that narrow slit glides past a specific part of the sensor takes 1 millisecond. But the full movement time of the curtains is longer.

And since the flash have a very short light time, the flash light would only light up a small part of the sensor. If going 1/4000 instead, an even smaller part of the sensor would be open to light when your flash unit flashes.

So the flash sync time relates to exposures long enough that one curtain have opened fully, having the full sensor accumulating light, before the second curtain starts to move to hide the sensor again.

The nice thing with a curtain shutter is that it allows extremely short shutter times with limited movement speed of the curtains. It is only the precision you can move the curtains with that controls the shortest shutter time.

It is possible to create a curtain shutter to allow faster travel. But it will affect the life time of the shutter. You really need to have extreme travel speeds to fully open one curtain before closing the second curtain if you want faster sync times.

That makes sense but in practice, the D800 has a faster shutter sync than the 5D3 and still have a longer shiutter life expectance.

Alex_Venom wrote in post #15406012
That makes sense but in practice, the D800 has a faster shutter sync than the 5D3 and still have a longer shiutter life expectance.

Yes. But when going for a faster shutter sync you need faster curtain movement. And for faster curtain movement, you have to settle for higher forces, which implies more wear. So you either get a lower shutter life expectancy, or you need to invest in more wear-resistant materials or in better material tolerances etc.

The 5D3 shutter assembly is not the worlds best or fastest. And the D800 doesn't have the best shutter sync available either. It is all a question of compromises. The faster shutter sync speed you go for, the harder it will be to design the shutter assembly to survive many actuations.

how about for mirrorless cameras + strobes? can it go faster than 1/200 ish?

Alex_Venom wrote in post #15406012
That makes sense but in practice, the D800 has a faster shutter sync than the 5D3 and still have a longer shiutter life expectance.

The difference between 1/200 and 1/250 is slight and both may even be within variance of each model depending on other conditions.

Shutter life expectancies are vary widely variable, to the extent that 150K versus 200K specifications might not count for much either.

To see differences that you can count on, look to the top-end models of both cameras.

I've read posts from a lot of people complaining about the 'loss' (of capability, I assume) and how important it is to them etc etc.

I am not sure what to make of this. The difference between 1/200 and 1/250 is 1/1000 (one thousandth) of a second. In the neighbourhood of 1/200, this is a 20% loss, hardly a 1/3 of a stop!

Is it that critical?

On the matter of older cameras synching at 1/500 (I am not sure, maybe even higher), this was achieved with in-the-lens Compur-type leaf shutters.

With certain limitations, the Hi-Sync feature of most flashes, allows much higher synching speeds that in-the-lens shutters cannot achieve (provided you have an application that you need more than 1/500...).

I don't know specs from many film SLRs but I would guess they all tended to 1/200 to 1/250 kind of range. The only cameras I can think of with higher sync speeds either had leaf shutters in the lens or they had electronic shutters.

The earliest Nikon CCD equipped dSLRs had 1/500 sync speeds, because they did not have mechanical shutters at all.

I am just looking forward to a day when we have electronic shutters for these CMOS sensors. Let me sync at any ss. Some day.

The very early focal plane shutters on big cameras--all the way up to 4/5, but there were some medium format focal plane shutters as well--were around 1/30 sync speed.

From the 30s into the 80s, most film 35mm SLRs were limited to 1/60 shutter sync because they had horizontally moving curtain shutters--spanning the long dimension of the frame. The top Canon and Nikons got up to 1/80 sync speed.

The horror! Amazing that we survived!

Vertically travelling metal-blade shutters came in during the 70s with 1/125 sync speed, but they were very slow to take hold because of reliability problems and cost.

Then came polycarbonate-bladed vertical shutters in the 80s--both cheaper and more reliable, and then you saw sync speeds start to creep up to where they are now.

JeffreyG wrote in post #15406140
I don't know specs from many film SLRs but I would guess they all tended to 1/200 to 1/250 kind of range.

Most 35mm film SLR cameras, at least those made in the 1960s and 1970s that I am/was familiar with, had electronic flash sync speeds of 1/60 second or maybe a tad faster. My Nikon F cameras - the best available in its time - have a 1/60 second max sync speed.

You'd thunk that if man could build a pacemaker to be reliable ....