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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 ...
20
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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1/250 of a second is the maximum flash sync speed on Nikon D7000. This is the fastest shutter speed where sensor is fully exposed at a time. On faster shutter speeds, second shutter curtain starts moving before the first curtain has fully opened and there would be no moment where the flash could illuminate whole scene captured by sensor.
This speed is ...
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You 'kill the ambient' when you set the flash(es) power high enough so that at the chosen aperture, shutter speed and ISO the contribution made by ambient light is insignificant to the picture. In other words, taking the picture in full darkness with flash only while all other variables are the same would give you the same result.
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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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How to kill the ambient light
"Killing the ambient light" is a term used when you want to take a picture that is purely lit by flash, so that you have complete control over the lighting in the picture you are taking. It follows, therefore, that if you were to take the image without the flashes enabled, the image would be very heavily/completely underexposed....
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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 ...
11
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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In principle, your rationale is correct. However, there is no usable period during which an ordinary single flash is emitting at constant power.
The power of a typical on-camera flash quickly increases from zero to its maximum value in about 0.1 ms (i.e. 1/10 000th s). Then it exponentially decreases with a half-life of roughly 1 ms; i.e., it decreases 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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What does it mean? As Miguel says, it's overpowering the ambient light entirely. Indoors you can usually do this by increasing the shutter speed to the maximum sync speed of the camera (usually 1/200th or 1/250th). Increasing the shutter speed won't affect the flash exposure because it is so much shorter duration than the shutter speed. If that isn't ...
7
1/250 is not the shutter speed to use when flashing. It is simply the fastest shutter speed that can be used if you want the entire picture frame to be illuminated by a single flash from the speedlight. Google up "flash sync speed" and ye shall learn why this is so. Anyway, there is absolutely nothing to stop you from using flash at, say 1/50 second or 1/10 ...
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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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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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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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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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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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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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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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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 ...
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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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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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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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As you suggest the highest speed at which the shutter is at some point fully open will be faster than the quoted flash sync speed, to allow some variation in flash timing, probably just under a stop faster.
I don't have any information for the D7000, but the Canon 1D mkIII has sync speed of 1/250s with most flashes. When a Canon EX flash is used the camera ...
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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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