Art Schotz wrote:
It might be well noted that shutter speeds do have a significant effect outside, when using strobes, in order to control the ambient light.  Frequently, you can "cheat" the sync speed a little.

So you see, no generalization is worth a damn!  lol

TXPhotog wrote:
OK, I know that's a bit of an overstatement.  The shutter speed has to be slow enough to sync with the studio flashes, and the ambient light has to be small with respect to the exposure from the flashes.  "Nothing to do with" isn't quite accurate.  But for practical purposes, it's close.

Sigh.

Art Schotz wrote:
It might be well noted that shutter speeds do have a significant effect outside, when using strobes, in order to control the ambient light.  Frequently, you can "cheat" the sync speed a little.

So you see, no generalization is worth a damn!  lol

TXPhotog wrote:
OK, I know that's a bit of an overstatement.  The shutter speed has to be slow enough to sync with the studio flashes, and the ambient light has to be small with respect to the exposure from the flashes.  "Nothing to do with" isn't quite accurate.  But for practical purposes, it's close.

TXPhotog wrote:
Sigh.

lol. Try not to get too frustrated. There are those of us that are paying attention and learning from this.

RichBruton wrote:
While your statement is generally true, there are a few exceptions.

Any decent wedding photographer knows that "dragging the shutter" (setting the shutter speed to, say, 1/60) will allow some ambient light to warm/fill the frame in addition to the 'pop' you get from the strobe.

When I shoot a model standing in front of water, such as a pool or a pond at the golden hour (sunset), I frequently will bounce the flash into a gold reflector to get the bright 'pop' of strobe light on the model, but I want to the water to burn more into the frame ... so I will intentionally slow the shutter speed down (1/60 or 1/30) to get the rich colors off the sunset reflections on the water.

Also, when shooting at night, sometimes I will shoot time lapse with a strobe flash during the exposure.  This works great, for instance, when you want to catch a trail of taillights on a curvy road, followed by a 'pop' from the flash to illuminate the entire car at the end of the trailing taillight stream.

I occasionally also shoot at midnight on the beach ... using the full moon with a 4-6 second exposure (makes the sky light up and the water look awesome).  During the open shutter, I will fire a strobe by hand to illuminate a model standing in frame.

All of these examples use ambient light in concert with artificial (strobe) light ... and therefore shutter speed DOES matter.

But when your strobe is brighter than your ambient light, and the strobed subject fills the frame, then your point is completely correct ... shutter speeds are irrelevant as long as you are within sync speed range.

TXPhotog wrote:
OK, I know that's a bit of an overstatement.  The shutter speed has to be slow enough to sync with the studio flashes, and the ambient light has to be small with respect to the exposure from the flashes.  "Nothing to do with" isn't quite accurate.  But for practical purposes, it's close.

Sigh.

The purpose of my post WAS NOT to discuss all the fancy ways that people can deliberately mix ambient and studio flash lighting.  It is to make a simple point about the contribution of a flash to exposure, and how that relates to shutter speed, which some people seem not to understand.

TXPhotog wrote:
When shooting with studio strobes, the exposure has nothing to do with the shutter speed!

All very nice replies, but wouldn't "studio" be one of the key words here?

M W Photography wrote:
All very nice replies, but wouldn't "studio" be one of the key words here?

That is the intent, although those determined to find "exceptions" will point out that "studio" lights can be used outdoors, or in the studio in conjunction with ambient light . . . all of which misses the point.

RickMartin wrote:
I've had similar discussions with "professional" photographers who will swear blind that it is the focal length of the lens which affects perspective, and not one's point of view.

It's fun up to a point, but I normally eventually reach the stage where I just shake my head and walk away.

I'm wondering if there could not be a "misconceptions about photography" thread in here somewhere . . . .

Let's not forget "72 dpi".  But I digress . . . .

cassios co  wrote:
Yeah, You want to shoot within 1/100 or 1/200 that's it for strobes. The industry average is 1/125

Not with leaf shutter film cams it's not..nor with Nikon strobes and Nikon cams..probably equally false with Canon's too. And then there are all thso e P&S cams that defy the sync generalization too.

R Michael Walker wrote:
Not with leaf shutter film cams it's not..nor with Nikon strobes and Nikon cams..probably equally false with Canon's too. And then there are all thso e P&S cams that defy the sync generalization too.

The important point being:  know what your particular equipment's sync speed is, and don't shoot at shutter speeds above it.  If you shoot at shutter speeds at or below the sync speed, the exposure from the flash won't change.

(Yes, I know that for some leaf shutters, the sync speed is higher than the flash duration.  Again, it's a minor exception that detracts from the point being made.)

TXPhotog wrote:
Happened again this last weekend, when a working pro told me, with a straight face, that if I were to go from 1/200th of a second to 1/100th, my exposure would go up one stop.  And we were shooting with his Profoto flashes.

No.  It doesn't work that way.  Really.

it does work that way to a degree.  if you are dealing with ambient light, changing your shutter sped like that will increase your ambient by a stop.
depending on what brand of strobes ad what power they are at, it might affect the strobe too.  ....if they are a cheap model with a long flash duration

TXPhotog wrote:

The important point being:  know what your particular equipment's sync speed is, and don't shoot at shutter speeds above it.  If you shoot at shutter speeds at or below the sync speed, the exposure from the flash won't change.

it might.....i have noticed an issue with not being able to achieve max sync speed, because of using a radio slave...in theory, it makes no sense to me, but in reality the radio slave it making sync slower.  strange!

Ethereal Pixels  wrote:
And so it goes... just because someone can afford triple digit or quad digit prices for a camera body doesn't mean that their IQ exceeds double digits.    Then again, I can probably bring them to the point of a mental seizure by pulling out one of my SBs, putting it in CLS mode, and then shooting at 1/2000 of a second!

i could do that with a profoto or broncolor strobe.


why be shy....take that puppy up to 1/8000

i always thought that was a pretty sweet feature of the slrs with their flashes
it does decrease output power as you go faster though, but still pretty awesome

Seattle Photo wrote:
it does work that way to a degree.  if you are dealing with ambient light, changing your shutter sped like that will increase your ambient by a stop.

No, actually, it won't, unless the contribution to total exposure from the flash is very small.  Please go back and read ALL of the original post.

Seattle Photo wrote:
depending on what brand of strobes ad what power they are at, it might affect the strobe too.  ....if they are a cheap model with a long flash duration

See above.  There are a VERY SMALL number of equipment cases - a trivially small number, for this purpose - where there is a relationship between shots at max sync speed and exposure, but even for those, it is NOT TRUE that shutter speed can be used to control exposure, yielding a one stop difference in exposure for a one-stop change in shutter speed.

J. Stakeman wrote:
Its frustrating isn't it?

Its amazing how persistent ignorance can be.. I've almost pulled my hair out over similar discussions on the inverse square law.

Me too.  Until on a discussion here I was shown to be wrong in my own understanding of it.  I had always assumed that since the "point source" assumption was violated when using soft boxes, the inverse square law would not work in the studio.  A nice person pointed out that it still does work (give or take a little margin for error), I tested it, and he was right.

TXPhotog wrote:

Seattle Photo wrote:
it does work that way to a degree.  if you are dealing with ambient light, changing your shutter sped like that will increase your ambient by a stop.

No, actually, it won't, unless the contribution to total exposure from the flash is very small.  Please go back and read ALL of the original post.


See above.  There are a VERY SMALL number of equipment cases - a trivially small number, for this purpose - where there is a relationship between shots at max sync speed and exposure, but even for those, it is NOT TRUE that shutter speed can be used to control exposure, yielding a one stop difference in exposure for a one-stop change in shutter speed.

um, yes it will.


the basic rule is that aperture controls the flash and shutter speed the ambient.  it is a bit more complicated then that, but if i am balancing daylight with the strobe, then if i change my shutter speed, it WILL affect the ambient exposure.


it's just simple. go try it.  i do this with 90% of my outside work

Seattle Photo wrote:
i could do that with a profoto or broncolor strobe.


why be shy....take that puppy up to 1/8000

With what camera?

TXPhotog wrote:
With what camera?

with none .. all strobes sync at 1/250 max

TXPhotog wrote:

Me too.  Until on a discussion here I was shown to be wrong in my own understanding of it.  I had always assumed that since the "point source" assumption was violated when using soft boxes, the inverse square law would not work in the studio.  A nice person pointed out that it still does work (give or take a little margin for error), I tested it, and he was right.

sure it does.  it's just that the front of your softbox is the source of the light now for that equation and the light head is the origin

GSP - Envy wrote:
you are right but not fully ... try drooping it to 10 sec exposure .. bet you your pic will look different from 1/200 hehe
it doesn't play a role (big role) with the stobes but you still have ambent light all around you

So you have missed the several comments, including the one in the OP, about ambient light?

GSP - Envy wrote:

with none .. all strobes sync at 1/250 max

either you are joking or just ignorant

GSP - Envy wrote:
with none .. all strobes sync at 1/250 max

Wrong.  Sync speed is a function of the camera, not the strobe, and there are many cameras with sync speeds higher than 1/250th.

TXPhotog wrote:

So you have missed the several comments, including the one in the OP, about ambient light?

i jumped the gun

Seattle Photo wrote:
it does work that way to a degree.  if you are dealing with ambient light, changing your shutter sped like that will increase your ambient by a stop.

TXPhotog wrote:
No, actually, it won't, unless the contribution to total exposure from the flash is very small.  Please go back and read ALL of the original post.


See above.  There are a VERY SMALL number of equipment cases - a trivially small number, for this purpose - where there is a relationship between shots at max sync speed and exposure, but even for those, it is NOT TRUE that shutter speed can be used to control exposure, yielding a one stop difference in exposure for a one-stop change in shutter speed.

Seattle Photo wrote:
um, yes it will.


the basic rule is that aperture controls the flash and shutter speed the ambient.  it is a bit more complicated then that, but if i am balancing daylight with the strobe, then if i change my shutter speed, it [/b]WILL affect the ambient exposure.[/b]


it's just simple. go try it.  i do this with 90% of my outside work

Of course it "will affect" ambient exposure.  What it will NOT  do is make a one stop change in exposure based on changing the shutter speed one stop, unless the contribution to the exposure from the flash is very small.

Seattle Photo wrote:

either you are joking or just ignorant

i should have said "on my camera"

TXPhotog wrote:

So you have missed the several comments, including the one in the OP, about ambient light?

Not everyone reads the whole thread on MM.