Beginner Outdoor Flash

[Derek.Laurence]

Hey Guys,

Can I start by saying Ive just been awarded my Happy Birthday Trophy, and have loved every day of being part of this community. Ive learned so much from many users and find everyone really friendly! Lets hope for more years of the same

Now, to the point..... Im going out later with my son to experiment with off camera flash balanced with daylight.

I obviously know how to obtain a good exposure in daylight using the exposure triangle

I know that using studio lights/ flash the exposure is solely governed by the aperture, assuming I am within the sync speed (ill be working at iso 100)

So the bit thats puzzling me before i go and play, If I get my exposure for daylight lets say f/5.6 @ 1/500s iso 100 for argument, is it just a case of altering my flash power (or distance) to get the exposure balanced?
Ive seen vids saying shutter speed controls ambient light. Yup, i get that. but then how do I balance because surely the aperture has an effect on the ambient light as well.

Or am I looking at it the wrong way and I need to get an aperture suitable for the flash first and then get the relavant s/s for that aperture?

Im sure the answers simple and im overthinking it.


Thanks in advance


Derek

 

[HoppyUK]

You've got it right. The old 'aperture controls flash exposure' was never really true, but if you were shooting in a studio, with no ambient light, and your ISO was fixed by the film, then it was a kinda rough shorthand.

In fact, the only thing that doesn't affect flash exposure (when not in high speed sync mode) is shutter speed - everything else does. Aperture, ISO, flash output, flash zoom setting, any light modifier used, and distance. Light falls of rapidly with distance, due to the inverse square law, and if you double the distance the brightness is reduced to one quarter - a drop of two stops.

Some comments: clear sun is very bright and this limits what's possible with a hot-shoe gun. Things get much easier when it's overcast, or in shade, or when the sun is lower. Fill-in flash doesn't need so much power, as it's only lifting the shadows, and as a rule it looks better when the flash is subtle rather than too strong. But if you want the flash to be more dominant or even to over-power the sun by a couple of stops (to get that fashionable dark sky/background look) then that needs tons of power in bright daylight - like several flash guns ganged together.

Also, shutter speed does have a knock-on effect in that it reduces the brightness of the ambient light relative to the flash, so when you need max flash brightness, push the shutter speed right up to the x-sync limit.

 

[Derek.Laurence]

Cheers Hoppy

I had a play in the house just there exposing for outside through the window and basically guesstimating the flash exposure.

I watched the most boring youtube video(

) but he kinda got the point across.

Without a flash light meter (its on the Xmas list unless someone can recommend a cheap version) then think I'm just going to need to wing it in the meantime

 

[HoppyUK]

That vid is as much a TFC product promotion as instruction. You don't need a flash meter.

The right flash/ambient balance is both variable and subjective - suck it and see. The best look will rarely be exactly in balance with the daylight. You'll soon get to know roughly where you are, then check what it looks like on the LCD, making sure you can see that clearly when in bright sun.

I think you're using a manual gun? That's good for learning here, as it's the only way to know exactly what power setting the gun is working at.

 

[Derek.Laurence]

Yeah Im currently using a YongNuo YN560-II with my Canon 30D ( think i need to update my equip list on here)

I got a cheap remote trigger through the week so I need to get up to speed with it Ive never used eTTL before so have always had the learning priviledge of having to set power manually etc.

Thanks for the help Hoppy

 

[pjm1]

Also bear in mind your flash sync speed... you won't be able to use "normal" flash above 1/250 (for my camera it's actually slower at 1/180th). Many flashes have a high speed sync capability but that actually lowers the power of your flash even further. The challenge I find with flash balancing outside is actually getting the SS down low enough - if you have any ND filters you might benefit from them.