Shutter controll during flash

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DrDale

Senior Member
Hi,
I have a D200 with the 60mm Micro Lens and a Polaroid ring flash.
I want to set a high F stop to get maximum depth of field. When I do that on Manual or S or A the shutter stays open after the flash and continues to gather ambient light until it shuts the shutter. This messes up the picture.
How do I get the camera just to measure the flash light and shut the shutter after the artificial flash light?
 
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FastGlass

Senior Member
Setting a high f-stop reduces the amount of flash the camera records. Remember aperture controlls flash exposure. Setting the aperture to f-16 or 22, you're blocking any flash from creating a good exposure. Sounds like you're flash isn't powerfull enough to compensate for it.
 
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WayneF

Senior Member
DrDale said:
Hi,
I have a D200 with the 60mm Micro Lens and a Polaroid ring flash.
I want to set a high F stop to get maximum depth of field. When I do that on Manual or S or A the shutter stays open after the flash and continues to gather ambient light until it shuts the shutter. This messes up the picture.
How do I get the camera just to measure the flash light and shut the shutter after the artificial flash light?
Click to expand...

Shutter speed is what makes the shutter speed stay open longer (it is not the flash).
A TTL flash is still automatic flash exposure in ANY camera mode (including M mode).

If in camera S or M mode, the shutter speed is whatever you set it to. So set it faster (and of these two, chose M mode, so that you can set f/16 too). The D200 will sync flash up to 1/250 second. This shutter speed will not affect the flash exposure. The flash is faster than that. The shutter speed affects any continuous ambient light, about which I doubt you are interested in.

So set f/16 and 1/250 second in camera M mode. I assume a close subject distance, and maybe your flash has enough power to do f/16? Higher ISO will help it do it if any issue.


In camera A or P mode, if with flash in less than bright light, normally shutter speed will be the 1/60 second minimum wit flash (not slower). However there are ifs and buts, one of which is if slow sync or rear curtain sync, which won't do that - so if you saw slower, it was not regular front curtain sync.
 
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Mfrankfort

Senior Member
Manual Mode, Set shutter to 200 (or fastest sync speed), meter and adjust flash until you get the F-stop you want (say 11..16..)... dial that into camera. Boom. Proper exposure.
 
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DrDale

Senior Member
The ring flash stopped working after 3 or 4 outings, so back to the SB-400. I am curious about why I see the flash through the viewfinder during the shot. I thought that the mirror would be up during the time the flash happened.
 
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WayneF

Senior Member
DrDale said:
I am curious about why I see the flash through the viewfinder during the shot. I thought that the mirror would be up during the time the flash happened.
Click to expand...


That would be the TTL preflash. The digital TTL metering is in the viewfinder, so it has to be done immediately before the mirror rises. We can see it immediately before the mirror. Humans watching it from outside the camera cannot distinguish it from the final flash.
 
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DrDale

Senior Member
Is that why my Vivitar SF-3000 slave flash goes off when the Speedlight it does not show up on the picture? It is triggered by the preflash before the mirror goes up?
 
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WayneF

Senior Member
DrDale said:
Is that why my Vivitar SF-3000 slave flash goes off when the Speedlight it does not show up on the picture? It is triggered by the preflash before the mirror goes up?
Click to expand...

Yes, that would be the usual case... optical slaves simply cannot be triggered in sync from automatic flash. Because the preflash triggers them too early, before the mirror goes up and the shutter is opened.

Set your triggering flash to manual flash mode, and it will work. The slave is manual anyway. This manual trigger flash normally could be set to a very low level if you did not want it to interfere (contribute) with the picture.

Some (a very few) slaves have a option, to ignore the first flash (preflash from digital automatic TTL flash), and instead to trigger on the second flash seen. This can work then, but the automatic flash will be its usual full value (as opposed to a low level trigger). That can work with normal hot shoe TTL flash, but it still has no hope of working with the more complex Commander system.
 
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