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I just read that a normal flash illuminates a scene within a 1/250th of a second. (A flash would keep the scene illuminated for a 1/250th of a second, right?
In general, that's wrong.
Flash duration is flash duration and sync speed is sync speed.
Apples and oranges.
The 1/250th of a second is the sync speed of (many) cameras. That's basically the ...
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That is a true statement, but it misses the big point. (As the shutter would see it), it would simply become continuous light, like any incandescent light bulb (always On for the full shutter duration would be indistinguishable from continuous light). Like continuous light, there would be no motion stopping ability at all.
And even a 500 watt light bulb ...
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Why?
Fundamentally, it's because of the way flashes work. Flashtubes generate light by discharging a capacitor through a xenon-filled tube. The resulting electric arc produces bright white light. But a continuous electric arc would produce a lot of heat, which would weaken the tube, and it would consume a lot of power, which batteries cannot supply for long....
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The shutter speed now is 250
From what I can tell from the Google, the Nikon D3100 has a flash sync speed of 1/200. So, you're setting your shutter speed too fast and the curtain is already starting to close when the strobes pop.
Your maximum should be 1/200. But, honestly, there's no reason to even flirt with the edge that much. You can go down to 1/125 ...
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The limitation has to do with synchronizing the length of the exposure with the length of the flash burst. The flash does not go off immediately...it occurs a fraction of a moment after the shutter has opened, and the burst only lasts a fraction of the time the shutter is open. This is necessary to produce a proper exposure when using a full-powered flash ...
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You could use an ND filter or even a polarizing filter (which you probably already have) to give yourself another couple of stops.
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The shutter sync is limited simply by how fast the shutter can move in the same way there is a limit to how high a car engine can rev. Increasing these limits increases the demands placed on materials, design and longevity.
Another limit is the distance the shutter must travel (which is determined by the size of the sensor, a full frame shutter has to ...
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That camera with 1/60 sync (and says ASA) must be at least 40 years old. :) More modern cameras commonly allow 1/200 second shutter with flash.
But this limitation (of not allowing flash with 1/1000 second shutter) is due to the type of shutter in the camera. It is not a property of the flash, electronic or bulb. It is a property of the camera shutter.
...
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Your camera is limiting your shutter speed to the 60D's maximum sync speed. If you were to use a faster shutter speed, you'd have black bars at the top and/or bottom of the frame, because the shutter curtains would be covering part of the sensor when the flash burst goes off. The only way to use a faster shutter speed than 1/250s with flash it to use high-...
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Cameras that have a mechanical focal-plane shutter have two curtains, a front and a rear. For longer exposures, the front curtain opens and starts the exposure, then the rear curtain closes to end the exposure.
The mechanical shutter is relatively slow, so to create a quick exposure, the rear curtain must start closing before the front curtain fully opens. ...
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Yes. What you're envisioning is something that's actually used by some TTL-capable radio triggers to allow faster shutter speeds with manual flashes and studio strobes: it's called tail-sync (aka "HyperSync", "Supersync", etc.).
The problem, as Loong has pointed out, is that the light/power output of the flash pulse is not even and constant during the ...
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Others have addressed the technical side of why strobe flashes are extremely fast.
There are alternative photo lighting technologies which do exactly what you say. This answer addresses the pros and cons of them:
LED-based 'flashes' as seen in phones etc. – these turn on a bright LED for the time it takes to take a photo, then turn it off. They're commonly ...
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The problem that is solved via high speed sync has nothing to do with the power of the flash and everything to do with the curtain transit time of the camera. Above a camera's sync speed the second curtain begins to close before the first curtain is completely open. Therefore very precisely timed multiple flashes must be emitted from the flash as the open ...
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I just read that a normal flash illuminates a scene within a 1/250th of a second. (A flash would keep the scene illuminated for a 1/250th of a second, right?
Sort of, depending on the specifics of the flash unit and the power setting. For example, a Canon 580EX Speedlite set to full power discharges over 1/250s according to Andy Gock's Actual Measured Flash ...
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The issue is your shutter speed in combination with the fact that the YN-560 models are all manual-only flashes. See: Why is my camera limited to a shutter speed of 1/250th when the flash is up?
Essentially, your camera controls your shutter speed by changing the size of the gap between the two shutter curtains. At your camera body's maximum sync speed, the ...
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At 1/250, you are trying to exceed the x-sync speed of the 6D (which is 1/180, as you have found), which explains the black bar.
Don't forget that on the 450D, as a crop-sensor camera, the shutter has less distance to travel, so doesn't need to move as fast to give the same exposure time, which explains why some full frame cameras have a slower x-sync speed ...
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Great photo! This is a common difficulty that is even more of a problem when shooting outdoors.
The simplest solutions, as outlined above, would be using a reflector rather than a flash (this could work really well as you have a big window) or using a sheet to reduce the incoming light from the window and either something similar over your flash, or moving ...
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If you are using the flash as the main source of light, it won't matter, since the flash pulse is usually much, much faster than the sync speed. Details below, but if you're primarily lighting with flash and are at less than full power, the shutter speed is irrelevant and your exposure will be something like ¹⁄₁₀,₀₀₀th of a second.
If, instead, you are ...
answered Dec 26 '14 at 13:15
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If the flash were to light up before the shutter opens and turn off
after the shutter closes, there would never be flash sync problems.
There would also be lower efficiency as some of the light output by the flash that is captured by the lens would not be captured by the camera. It takes about 2-4 milliseconds for a mechanical shutter curtain to transit ...
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Before electronic flash became the norm, we used flash bulbs. These were a one-time use bottle of sunlight. Typically they consisted of a glass envelope filled with oxygen. The bulb contained a filament similar to an ordinary tungsten lightbulb. The tips of the support wires upon which the filament was mounted, were tipped with phosphorous. The glass bulb ...
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First off, that's a really lovely photo :-)
Secondly, did you need to use flash at all? Could you maybe just use a reflector to reflect the ambient light onto the baby? And if you did, you could consider bouncing it off the ceiling or wall to further reduce its power. Or instead of a white umbrella, you can get black ones too that would absorb more of the ...
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You have a couple of options to cut down on the amount of light.
An ND filter on the camera
Add more diffusion to the existing lights
Use a trigger with TTL capabilities - This one is only useful if the flash is what is causing your light to be too bright. If the natural light alone is too bright than you will have to take one of the first two options. ...
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The sync speed itself doesn't change, as that is defined by how quickly the shutter curtains move, but what is happening is the trigger is adding a delay, which throws off the timing. What ought to happen at 1/200s is that the first curtain reaches the top, the flash fires, then the second curtain starts closing immediately from the bottom. However due to ...
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Well. the max sync speed presupposes that the slave flash reacts instantly to the trigger. If it takes any amount of time at all for the slave to react, that is going to eat into your sync speed as the second curtain will have started to close before the slave flash actually fires.
So I'd say that yes, you would be better off to back off some from max sync ...
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Most dSLRS use focal plane shutters with two curtains. The first curtain "opens" the shutter, and the second one "closes" it. The size of the gap between the two shutters determines the shutter speed. The smaller the gap, the faster your shutter speed. When you reach your maximum sync speed (usually around 1/200s, for most cameras), that's the fastest ...
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This is how Canon DSLRs work, in Av and Tv modes the camera exposes for the ambient light and only uses the flash for fill.
To use the flash as the main light source you have to use full auto or P mode.
or - the best options is to do what you did and use M mode, in manual mode with the built in flash or an external flash in TTL mode you can use the shutter ...
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Godox has several lines of flashes (everything from speed lights to studio strobes) that are manual with HSS. The challenge is HSS requires the trigger interface with the cameras proprietary flash protocols and so if you're doing all that you might as well do TTL. Godox gets around this by making HSS an off-camera only function. So the flash has a single ...
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You see the curtain of your camera: nice, no?
If you want to avoid that with mark III , use a shutter speed lower than 1/200s
You could use high flash speed sync, but I am quite sure that your flash can't use that,
so with this flash, your only solution will be under 1/200s or use a ND filter to have less light entering your lens
Check this tutorial on ...
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Started out as a comment to Caleb's nice answer and accidentally turned into answer...
To start a (glowing) discharge high voltage is needed (called breakdown voltage). When the vacuum is broken down the resistance drops almost instantly from near infinity to near zero resulting in insanely high current and low voltage.
Only hard current sources can ...
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