I'm trying to make sense of page 48 of Neil's book. It says...
"if we decided to use manual flash, we'd meter for our manual flash to give us an exposure 2 or 3 stops below what we have set our cameras to for our background. For example, if we had settled on f/4 at 100 ISO, then we'd set our flash so that our flash meter tells us we need an aperture of f/2 (or thereabouts) for a correct exposure."
I just cannot get what he means by setting our flash so the flash meters tells us we need f/2. Can someone explain that to me?
Comments
Camera = f/4, 1/160, 400
Flash meter = 1/160, 400
You adjust the flash power until it shows f/4 on the flash meter and you have a balanced exposure.
Next you reduce flash power until the meter shows f/2 but you leave the aperture alone. Now you have less flash power or fill.
So if f/5.6 is the correct exposure, you'd meter for the flash as if it would be correct at f/2.8
and that would give you flash at 2 stops under .. which is perfect for fill-flash.
Follow this article as well:
http://neilvn.com/tangents/flash-photography-essentials/
Also thinking on your feet is not easy some times. The show is on. You just can't walk away from it for 20 minutes like when you are alone to give the brain a break. It is just experience and one day you will be able to it all while multi tasking.
ETTL works great and is a good option which I use a lot. I find if I have the time manual flash and my meter is just more consistent.
I am really trying to learn to use manual flash. I have always used TTL, and I am not happy with the inconsistencies with it. However, when I'm rushed and can't figure out what I'm doing, I usually go back to TTL!
Thank you so much for the help!
and that would give you flash at 2 stops under .. which is perfect for fill-flash.
Did you mean to write f/2.8 is 2 stops under? I thought full stops went from f/5.6 to 4 to 2.8 to 2. Am I getting that right or am I misunderstanding?
1 2 4 8 16 32 65
1.4 2.8 5.6 11 22 45 90 .........
f stop = Focal length / diameter of the lens iris.
e.g. A lens with a focal length of 100mm, with an internal lens iris diameter of of 10mm will produce an aperture of f10.
Because apertures relate to the area of circle then, (Area = ∏rxr), some of the numbers are rounded off, hence the 2.8, 5.6, 45 & 65 etc.
You are right though the difference between f2 and f5.6 is 3 stops - a small slip up on Neil's behalf.
I can forgive him