how your auto iso and flash works ?

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WayneF

Senior Member
alaios said:
So I have spent one more evening trying.
I think I get closer to what might be the problem. I think it is not that the camera ignores my -3 FEC but it does not have any more latitude for weaker flashing.
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That sounds very reasonable to me. If at high ISO and wide aperture, the picture cannot tolerate much flash, so it would be already at a very low level.

Last question since I am using manual mode to have a shutter speed I need, I wonder since I have my iso fixed and aperture, then turning the EC dial would make it equivalent to FEC.. right? Since now the EC only can change flash output since everything else is dialed in.
Let me know where I am wrong in all above
Regards
Alex
Click to expand...

EC does add to FC (EC affects both ambient and flash, except D750 has E4 menu to isolate them). I imagine the same minimum flash level would still apply.

Manual camera mode does not respond to exposure compensation. The camera settings are what you set them to be (except Auto ISO would still be automatic). The light meter will respond to EC, and the meter will indicate a different response with EC, but the manual camera settings do not change with the meter if in manual camera mode (excepting Auto ISO of course).

Same is also true of Manual flash mode, the manual flash level setting is whatever you set. FC or EC would have no effect on manual flash mode.

However, TTL or TTL BL flash mode is sill automatic flash with any camera mode including Manual, and is still affected by flash compensation (and also EC), even if manual camera mode settings do not respond to ambient.
 
A

alaios

Senior Member
WayneF said:
However, TTL or TTL BL flash mode is sill automatic flash with any camera mode including Manual, and is still affected by flash compensation (and also EC), even if manual camera mode settings do not respond to ambient.
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Exactly so still at manual mode with specific iso, aperture and shutter speed then I can use my exposure compensation button to very fast reduce or increase flash output. That is one more extra flexibility.
Question remains though on which iso settings and wide apertures would get me into the areas that my flash can not weaker... That I need to work more with my flashes.
Thanks you have been a great resource and help
 
J

jtgraphics

Senior Member
I did not bother reading all the posts so sorry if I cover something mentioned.
My general rule is when using flash on or off camera Auto ISO is always off you do not want the camera taking over exposure by altering ISO on you, you have lost control over exposure then.
If I am not shooting full manual I shot shutter priority only with flash.
By using shutter priority you you have full control of abundant light and ad flash to desired fill effect using iTTL you then adjust power of the flash using +/- FEC
I do not dial in EC when using flash, if you are looking to go to faster shutter speeds to drop abutment light you must set FP mode to go to HSS.

Outdoor fill flash I'll try for the 20-30% range (power depends on distance) I do have and use a light meter for this if I'm really concerned if its just a quick shot I do not worry about it to much,
 
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