# Impact of max sync speed of 1/160th? Off camera flash.



## bryguy_ASU (Jun 8, 2014)

Hi,

I'm relatively new to photography and I like to challenge myself to new aspects of this hobby. I'd like to learn some techniques with off-camera flash. 

I've been reading a little on strobist sites. Reading and watching stuff on modifiers, balancing light (i.e. ambient, key, fill, rim light, etc.), and trying to understand sync speed. 

Currently I have a Samsung NX300 and I'm going to get a couple of manual speedlights. Thinking of getting two Neewer TT850's, a lumiquest softbox or beauty dish, and a light stand kit that has shoot through umbrellas. 

I just learned, however, that the max sync speed is only 1/160th. Without high speed sync (HSS), what are my limitations? Would I just have blown out backgrounds in outdoor portrait photos in midday sun? 

Could i still achieve creative portrait shots in home studio conditions? Or outdoors when the sun is dimming? How about when it's a little bright outside?

 I just don't understand what I can and can't achieve with a 1/160 or slower sync speed. Is it even worth buying the flashes and modifiers for that speed or less?


----------



## Braineack (Jun 8, 2014)

small apertures or you can also use ND filters if you open it up a bit.


----------



## Overread (Jun 8, 2014)

Your camera isn't much slower than most current DSLRs on the marekt which cap out at around 1/200sec to 1/250sec. So your creative options are as big as the rest. 

The key to understand is that highspeed shutter sync is typically used to provide fill lighting. When the ambient light is producing most of the light for the shot and the flash is giving a small lift to the shadowed areas. It's a weaker form of lighting and also works by giving a series of pulses of light rather than a single pulse (which is why HSS isn't suitable for fast action because the pulses of light will cause minor blurring where that light influences the shot).


----------



## WayneF (Jun 8, 2014)

bryguy_ASU said:


> I just don't understand what I can and can't achieve with a 1/160 or slower sync speed. Is it even worth buying the flashes and modifiers for that speed or less?



Indoors, it won't make any difference at all.  The flash is simply faster than the shutter.  The shutter simply has to be open to allow the flash through.

See Capability of flash units for high speed photography  for an example.  All of those used about 1.5 seconds of open shutter.  The flash speed provided the motion-stopping capability.   The "trick" is that this was a dim room, where 1.5 seconds of shutter still would not pass much ambient room light (which could blur things if it did).

It's the same thing for flash pictures indoors.  Without the flash, maybe we would need 1/2 second at f/5.6.  Which is why we need flash there. With the flash, maybe 1/160 second at f/5.6, (or maybe more, brighter).   This shuts out the dim ambient, the flash becomes the total of the lighting.  And the flash is fast (called a speedlight), and there is no issue at all.   If using studio lights (with modeling lights), they can be bright, so that ISO 100, f/8 and 1/160 second probably does not pickup the incandescent modeling lights at all.

The sync speed issue is in bright sun.   Sunny 16 says bright sun needs about  f/16 at 1/ISO shutter speed,  say 1/100 second at ISO 100.  So f/16 at 1/100 second.

Or equivalent exposure is f/11 at 1/200, or f/8 at 1/400 second.

But if the flash cannot sync that fast (meaning, if the shutter is not open to pass the flash), then this is a limitation, cannot use those equivalents with flash.

 But... we can always use f/16 at 1/100 second.  Outdoors in bright sun, yes, the sun might still blur action, but 1/160 is fairly fast itself.  Generally, we cannot ignore the overwhelming sunlight, not like we can easily ignore dim indoors ambient.


----------



## KmH (Jun 8, 2014)

It helps if you understand the concept of a photographic 'stop'.

As mentioned most DSLR cameras have a flash x-sync speed of 1/200 or 1/250.
One stop slower shutter speed than 1/200 is 1/100.
1/160 is only 1/3 of a stop slower than 1/200 is, and 1/160 is only 2/3 of a stop slower than 1/250.

When using flash, shutter speed controls the ambient light exposure while lens aperture and flash output power control the flash exposure.

A limitation of using high HSS (Canon) or Auto-FP Sync (Nikon) is that the flash unit has to fire multiple times during a single exposure because the shutter curtains are never fully open.
Some cameras, like the Nikon D40, D40x, D70, and D70s use an mechanical/electronic shutter than can sync non-dedicated flash units all the way to their max shutter speed of 1/4000. Those camera can sync dedicated flash units at up to 1/500. 1/500 is one more stop than 1/250.



KmH said:


> *What is a Stop?*
> 
> A 'stop' is a doubling (2x) or a halving (0.5x) of the amount of light and a stop is a fundamental photography concept.
> A stop change in exposure can also apply to shutter speed and ISO.
> ...


----------



## bryguy_ASU (Jun 8, 2014)

Thanks guys.. this is great stuff. I definitely have some homework. Feel free to keep pouring on the knowledge. Knowing is half the battle


----------



## Monday (Jun 8, 2014)

As mentioned just get some ND filters if you find the 160 sync limiting your aperture selections


----------



## bryguy_ASU (Jun 9, 2014)

Any recommendations on good nd filters? Also, regular or variable type?


----------



## daggah (Jun 11, 2014)

Essentially, what you need to keep in mind is that the slower your flash sync speed, the *more powerful* your flash needs to be to deal with bright ambient light.  

Keep in mind that shutter speed is the variable in the exposure equation that ONLY affects ambient light (barring some unusual situations that we'll avoid discussing for now.)  Your ISO settings and aperture settings both affect ALL light hitting your sensor, however.

Let's say you want to evenly balance ambient light with your flash.  We won't deal with more complicated situations like overpowering the sun for now.  If you've ever heard of the sunny 16 rule, you'll know that at ISO 100, 1/100s at f/16 on a sunny day will give you roughly the right exposure.  Note that 1/100s shutter speed is already very close to your sync speed.  You'd probably be at f/13 or so at 1/160s shutter speed.  That means that your flash has to output enough light to correctly expose your subject at f/13.   If you want to shoot at a larger aperture for depth of field reasons, keep in mind that putting an ND filter on your lens still requires an equivalent amount of power from your flash.  As far as your flash is concerned, f/11 with no ND filter is* the same *as f/2.8 with a 4 stop ND filter.

I can tell you right now that the vast majority of speedlights out there right now are not going to be able to put out enough light to correctly expose f/11-f/22, *especially* if you want to use something to diffuse and soften the light (umbrella, softbox, etc.)

So here's why a fast flash sync speed is desirable.  For every stop you can increase your shutter speed, you can open up your aperture 1 stop faster to achieve a balanced ambient light level.  Because your aperture setting affects both ambient and flash exposure, it's easier to correctly expose your subject with flash.

For simplicity, let's say that 1/125s will balance to f/16 (instead of 1/100s.)

1/125s = f/16
1/250s = f/11
1/500s = f/8
1/1000s = f/5.6
1/2000s = f/4
1/4000s = f/2.8
1/8000s = f/2

The situation becomes even more difficult and dire for speedlight flashes once you start talking about "overpowering the sun."  Remember, shutter speed is the only variable that affects _ambient_ light.  "Overpowering the sun" essentially means underexposing the ambient light so that what you're lighting with your flash(es) stands out more.  If you want to "overpower the sun" by 1 stop, now you're shooting at 1/250s at f/16, instead of 1/125s.  If you want 2 stops, you're shooting at 1/500s.  Etc., etc.

This is why powerful flash units (studio strobes, power pack heads, or the new variety of bare-bulb flashes) are necessary to balance or overpower the sun on bright, sunny days.  They're the only units powerful enough to put out enough light to overcome shooting at f/11 or f/16 (or using an ND filter.)


----------



## daggah (Jun 11, 2014)

Oh, and let's take a second to put things in perspective regarding flash power.  Remember that increasing light by 1 f-stop means doubling the light.  Some strobist photographers gang up multiple speedlights together to increase their power.  Going from one speedlight to two increases light output by one stop.  But to increase by another stop, now you need four speedlights.  Then eight.  Then sixteen.

In terms of power output compared to strobes, powerful speedlights put out around 60 w/s of light.  Two speedlights would be 120 w/s.  Four would by 240 w/s.  And so on.

So now you're looking at a 500 w/s studio strobe being more powerful than eight speedlights put together...


----------



## bryguy_ASU (Jun 11, 2014)

Wow daggah... exceptional read and valuable info here. I'm going to have to reread this and put it to practice to fully understand everything. 

Oh and yes, I am planning on buying a bracket to mount dual speedlights on a single light stand. 

Thanks for info! BTW, which is a decent ND filter that's inexpensive? Is standard or variable preferred?


----------

