Outdoor photo session - Balancing ambient and flash
Having a perfect balance between the ambient and flash light will mean that the flash is acting as a fill light. That's ok and works well, but to create a more dramatically lit portrait requires a difference balance.
Hi Bernie,
I really like your course — there’s a very genuine aspect about it.
Question on the video/photo with girl walking toward you and flash to her left. (along path lined with trees, outside)
The video said, 1/250 ss. yes, I get that – cuts out as much ambient as possible while staying in sync with flash.
ISO 100. Yes, I get that for above reasons.
f/8 on camera. Yes, that is about 1.5 stops down from ambient for the dramatic affect.
flash on full power – this I DONT get. Shouldn’t the flash be matched to your camera’s f/8? I’m guessing that the flash at full power will be f/16 or more power.
Why isn’t the flash matched to your camera?
Thanks,
Mike
Hi Michael, thanks for the question, I’m on holiday with limited wi-fi, but will respond shortly
Hi Mark,
Yes,the flash should put out approximately the equivalent of amount of light to the camera’s aperture. I can’t play the video because of the limited wi-fi, so I’m guessing a bit here about the settings I’d used. But had I been using a flash meter, I would have set the flash power to give me about F8, measured at the point where’s Grace’s head was going to be. But because I wasn’t using a flash meter, I just guessed that the flash power should be set to full or half power (I can’t remember which). I would have taken a couple of test shots beforehand with Grace standing at the right position. You say that as a guess the flash puts out f16 at full power, but remember that the flash power is affected by the flash to subject distance, so yes, it may provide f16 at 1 meter away, but not at say 3 meters away. Quite often in these circumstances, a single speedlight won’t provide enough power, so full power is a good starting point, and if that doesn’t provide enough light, then you have to move the flash closer to the subject, and if that isn’t enough, you need more light!
Why do British photographers never mention the Sunny 16 rule which a lot of American photographers teach, if you know the sunny 16 in relation to flash it really simplifies the subject of manual flash.For your students information the Sunny 16 was thought up in the days of film so that exposures could be based on the ambient light so on a bright cloudless day with the sun at its highest the exposure would be F16 at 1 over the iso, so if you were at iso 100 you would use 1/100 iso 200 you would use 1/200 etc etc. So a modern flash with a decent guide of 60 or more at 6-8ft from the subject would give you Sunny 16, if you take the time to learn the inverse square as well you can work out the exposures without having to take loads of test shots.So if you are at 6-8 ft with an unmoderated flash your flash would give you F16 @iso 100 -full power then for every f stop down you need 1 stop less and for every ISO stop you need 1 less, so as an example if you were shooting a model at 7 ft @ISO 400 and F5.6 you would need !/32 power from your flash if you drop you aperture to f2.8 then that is 2 stops which is 1/128 power. If you moderate the flash with an umbrella you need 1-2 stops more. Its easy to make youself a small chart starting at F16 full then put the ISO along the top and the Aperture down the side so you can see every exposure you would need
‘Why do British photographers never mention the Sunny 16 rule’
Probably because of the British weather!!
To be honest, I’ve never found the Sunny 16 rule that useful, maybe it is because of our weather, but I never shoot portraits in bright sunshine with the sun behind me. I’d always look for shade or even shoot towards the light. Also, the light can vary even on sunny day, hazy sunshine, slight cloud cover, later in the day etc…
As far as flash is concerned, using your example, have you actually tried shooting outside in good light at 1/32nd power? The flash won’t even register, unless of course you use a ridiculously high ISO, which would defeat the object.
Are you saying that a flash on full power is equivalent to mid-day sun? Hmm, maybe, I don’t know about that, but flashes differ in their power, and of course the flash to subject distance will affect the exposure.
All that aside, for this type of photo, outside when the sun is shining (other than early morning and at dusk), you’ll nearly always be using the flash on full power, and often that won’t even be powerful enough.
Cheers,
Bernie
Thanks for replying I know you cant shoot outside in good light at 1/32 power if you are in good light Sunny 16 then you will need ,with 1 flash full power at 6-8 ft as you know if you halve the distance say 3ft yiou can then shoot at 2 stops less but it really is a good way to get you in the ballpark.If you meter for the background and say you got F11 @ 1/100th then you can use a flash on 1/2 power but you really need 2 or more because as you say the recycle time and drain on batteries is too much.I have to thank you though because your course was the first one i saw on off camera flash and it learnt me so much but i think you created a monster ha ha, but the scale really comes into its own indoors when you are using multiple flash