Light Meters & Shutter Speed

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GaryK26

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Why do light meters have shutter speed setting?

Whilst I understand ISO / Aperture, I thought that with flash the shutter speed is [usually] irrelevant (in a studio environment)

So, consider "standard" settings of ISO 100, f8.0 and shutter speed 1/125th.

If I am shooting in manual (as you would in a studio), as long as I set my camera up as ISO100 and f8.0, my shutter speed doesn't necessarily need to be set at 1/125th...I could use 1/200th.

Am I missing the point somewhere?
 
GaryK26 said:
Why do light meters have shutter speed setting? Whilst I understand ISO / Aperture, I thought that with flash the shutter speed is [usually] irrelevant (in a studio environment) So, consider "standard" settings of ISO 100, f8.0 and shutter speed 1/125th. If I am shooting in manual (as you would in a studio), as long as I set my camera up as ISO100 and f8.0, my shutter speed doesn't necessarily need to be set at 1/125th...I could use 1/200th. Am I missing the point somewhere?
Click to expand...

Maybe some people use them for ambient too?
 
In a pro studio with all daylight blocked, the shutter speed is all but irrelevant. But a lot of people don't have that luxury, and with ambient light coming in via windows or skylights, the shutter speed can become relevant.

Also, there is a crude but reasonably accurate method of measuring the (roughly t.1) speed of a flash - set the shutter speed on the meter at (say) 1/125th, take a reading and note the indicated aperture. Now increase the shutter speed incrementally and re-test each time until the indicated aperture starts to change - you now have a pretty good indication of the flash duration:) This is known as the gate method.
 
When shutter speed is irrelevant, would you just choose a shutter speed to stop camera shake taking focal length of your lens into account ?
 
Yes talking about flash, eg if I was using a 200mm lens handheld I'd shy away from shooting at 1/30 sec. So if shutterspeed is irrelevant I'm gonna choose one to lessen cam shake up to the sync speed, if not using HSS.

It is my understanding fast flash durations are good for freezing subjects, rather than countering cam shake. Is this correct ?
 
If you had no ambient light and just using the flash you could shoot a 200mm at 1/30 if you wanted, as its the flash effectively creating the shutter speed, and it most likely it'll be significantly faster than 200th sec.

So yes, your flash is freezing the movement not your shutter speed, personally I shoot at around 200th when just using flash, regardless of lens.
 
treeman said:
Also worth noting if you're shooting outdoors some meters will tell you what the percentage of daylight is to flash, its something I use all the time.
Click to expand...

Sekonic do this, and you're right, it's very useful. Others, like Gossen, display the difference between flash and ambient in actual apertures, and you can then adjust the shutter till you get a the ratio you wish, which I find far more useful.
 
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GaryK26 said:
Why do light meters have shutter speed setting?

Whilst I understand ISO / Aperture, I thought that with flash the shutter speed is [usually] irrelevant (in a studio environment)

So, consider "standard" settings of ISO 100, f8.0 and shutter speed 1/125th.

If I am shooting in manual (as you would in a studio), as long as I set my camera up as ISO100 and f8.0, my shutter speed doesn't necessarily need to be set at 1/125th...I could use 1/200th.

Am I missing the point somewhere?
Click to expand...

hi, sorry if I've missed this earlier but you cannot shoot at 1/200th
if this is beyond the sync speed of your flash units.
typically 1/125s is the fastest you can go (ish)

so set your shutter speed 1/60-1/125s and then drop your ISO to the lowest possible to maximise quality if you can ( I think)
then set your aperture to the best for your lens and subject matter (lens sweet spot? but depends upon your intentions required DOF)
then set the power of your flashes as required with subsequent minor changes in your aperture for the perfect exposure imho.
there are 3 variables on the camera of course, but also the lighting is a variable which you can control and adjust

This is my simple understanding and is subject to further education! thanks
 
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