New tutorial, the best shutter speed for flash

Garry Edwards

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Questions get asked about this all the time, but a lot of people don't seem to get the fact that, in the studio, it's the flash that provides the exposure and stops the action, not the shutter speed.

So, I've written a short tutorial on the Lencarta lighting blog to explain it.
 
Well written article, thank you.

This will come in handy for me as I'm just starting out with studio lights
 
That is certainly going to be usefull for any one going into studio flash work. But many amateurs use their normal shoe flashes with or with out modifiers or reflectors both inside and on location.
for them the option of using high speed flash settings become an reality, where the flash fires repeatedly and the camera can be set up to its highest available speed.
Every thing has a down side and in this case it is a great reduction in the available power of the flash.
However when this technique is used the shutter retains the stopping power and the flash becomes like a continuous light.

A similar consideration comes into play when using a studio camera with a bladed shutter as they are synchronised to capture the flash during their fully open phase . But even at their highest speed do not result in cut off. So they can be used equally well at any speed. This makes it very easy to balance ambient with flash.
 
Thanks Garry. Easy to read, informative tutorial.
 
Thanks Garry. I have learnt a lot from that.
i saw a YouTube by Mat Granger saying he uses shutter speed to control the background brightness. He was using a single speedlight through a brolly.

PS great way to show of your reward ;)
 
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That is certainly going to be usefull for any one going into studio flash work. But many amateurs use their normal shoe flashes with or with out modifiers or reflectors both inside and on location.
for them the option of using high speed flash settings become an reality, where the flash fires repeatedly and the camera can be set up to its highest available speed.
Every thing has a down side and in this case it is a great reduction in the available power of the flash.
However when this technique is used the shutter retains the stopping power and the flash becomes like a continuous light.

A similar consideration comes into play when using a studio camera with a bladed shutter as they are synchronised to capture the flash during their fully open phase . But even at their highest speed do not result in cut off. So they can be used equally well at any speed. This makes it very easy to balance ambient with flash.
Well, this tutorial is for people using flash in the studio.. If they're using hotshoe flashes in the studio then of course they can freeze movement simply by dialling down the power, the shutter speed is irrelevant.
I'm not a great fan of HSS to be honest, it has exactly the same drawbacks as the old FP flash bulbs that preceeded it,. except for the cost of course. But I do like tail end sync for when fast shutter speeds are needed, and as it says in the tutorial, that's what I plan to cover in the next episode.
Thanks Garry. I have learnt a lot from that.
i saw a YouTube by Mat Granger saying he uses shutter speed to control the background brightness. He was using a single speedlight through a brolly.

PS great way to show of your reward ;)
I haven't seen that video, but he must have been using either HSS or tail end sync
 
Aperture controls flash.

Shutter speed controls ambient.

It took me about two years to get my head round that very simple principle :eek:
 
Except it's not quite right Adam. I see this in tutorial videos from some fairly well known names and it's no wonder people get confused about mixing flash and ambient. (Note Garry doesn't say this in this article ).

Shutter speed controls ambient/continuous light (lets just assume normal sync speeds here)
Aperture controls BOTH flash and ambient.

Ambient light does not become immune to aperture settings because you start using a flash.

Owen


Aperture controls flash.

Shutter speed controls ambient.
 
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Except it's not quite right Adam. I see this in tutorial videos from some fairly well known names and it's no wonder people get confused about mixing flash and ambient.

Shutter speed controls ambient/continuous light (lets just assume normal sync speeds here)
Aperture controls BOTH flash and ambient.

Ambient light does not become immune to aperture settings because you start using a flash.

Owen

Technically speaking no, but I'm not a technical kind of guy. There are lots of "rules" in photography that aren't entirely accurate. But they're still useful to use as a guide when you're trying to learn. Hence why a lot of people use that method in tutorials.
 
I'll agree it's a start (getting that shutter doesn't affect the flash ) however I can't agree that it's just a technicality Adam - it's a key concept. If you believe this is right, you'll be wondering all day long why your background goes up and down when you change your aperture to adjust your flash exposure. Stop down your aperture by 1 stop to reduce flash exposure? Open up the shutter speed by one stop to compensate for the background.
 
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I'll agree it's a start (getting that shutter doesn't affect the flash ) however I can't agree that it's just a technicality Adam - it's a key concept. If you believe this is right, you'll be wondering all day long why your background goes up and down when you change your aperture to adjust your flash exposure. Stop down your aperture by 1 stop to reduce flash exposure? Open up the shutter speed by one stop to compensate for the background.

Exactly, as a rule to get a newbie started, it's useful.
 
Exactly, as a rule to get a newbie started, it's useful.
Yes, it is useful, as an aide memoir, and it's a good idea to simplify things in the mind so that they stick. But Owen is right, it falls apart outside the studio, where ambient light levels are high enough to be a factor.

What is important though is that people understand the concept, even if the concept doesn't actually apply to all situations. My reason for writing the tutorial is simply that a lot of people don't seem to understand that, in the studio at least, the shutter has no real function other than to be fully open when the flash fires. I understand why a lot of complete beginners don't understand the concept, but some people who should know better, don't :(
 
The first flash I used was flash powder with unsynchronised flash..
you calculated the exposure with the provided table and set the aperture.
you simply opened the shutter or removed the lens cap, fired the flash in the pan with the flint mechanism, then closed the shutter.

I have no idea what the equivalent shutter speed was, but it was suffient to capture the started expression.

we still use the expression flash in a pan.
 
Technically speaking no, but I'm not a technical kind of guy. There are lots of "rules" in photography that aren't entirely accurate. But they're still useful to use as a guide when you're trying to learn. Hence why a lot of people use that method in tutorials.

Except that the "Rule" is not quite as stated.
Adjust for flash with the aperture
And then
Adjust for ambient with the shutter speed
 
Technically speaking no, but I'm not a technical kind of guy. There are lots of "rules" in photography that aren't entirely accurate. But they're still useful to use as a guide when you're trying to learn. Hence why a lot of people use that method in tutorials.

Sorry Adam, but it's not a useful phrase and is plain misleading IMHO. Aperture affects everything, ISO affects everything, only shutter speed does not affect flash at normal x-sync speeds. Surely nothing is easier than that one fact?

ps Cue Garry for correct attribution for the saying 'flash in the pan' :)
 
Sorry Adam, but it's not a useful phrase and is plain misleading IMHO. Aperture affects everything, ISO affects everything, only shutter speed does not affect flash at normal x-sync speeds. Surely nothing is easier than that one fact?

ps Cue Garry for correct attribution for the saying 'flash in the pan' :)

Interesting. I'll bare that in mind for future posts.
 
Sorry Adam, but it's not a useful phrase and is plain misleading IMHO. Aperture affects everything, ISO affects everything, only shutter speed does not affect flash at normal x-sync speeds. Surely nothing is easier than that one fact?

ps Cue Garry for correct attribution for the saying 'flash in the pan' :)
OK, I'll walk into that one:)
"Flash in the pan" actually derives from matchlock and flintlock guns, where, when the trigger was pulled, caused a flash in a small pan filled with black powder (gunpowder) which, in turn, was supposed to ignite the powder charge in the barrel. Sometimes it worked, mostly it didn't and there would just be a flash in the pan, and a misfire, hence "flash in the pan"
The first flash I used was flash powder with unsynchronised flash..
you calculated the exposure with the provided table and set the aperture.
you simply opened the shutter or removed the lens cap, fired the flash in the pan with the flint mechanism, then closed the shutter.

I have no idea what the equivalent shutter speed was, but it was suffient to capture the started expression.

we still use the expression flash in a pan.
You've forgotten to mention the fire extinguisher :)
 
OK, I'll walk into that one:)
"Flash in the pan" actually derives from matchlock and flintlock guns, where, when the trigger was pulled, caused a flash in a small pan filled with black powder (gunpowder) which, in turn, was supposed to ignite the powder charge in the barrel. Sometimes it worked, mostly it didn't and there would just be a flash in the pan, and a misfire, hence "flash in the pan"

You've forgotten to mention the fire extinguisher :)

I doubt things ever caught fire, rather than hair got singed.
Though some poor quality stuff burnt rather slowly and was quite scary if it fizzled.
The biggest problem could be smoke, some made a white smoke that sort of imploded and others a dark smelly cloud.
I would love to see what health and safety would make of it.
 
And here is the second part of my tutorial on shutter speeds with flash.

Here, we have gone outdoors, where the shutter speed really does matter.
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