How to use flash fill - 10D & 550ex

[Sean Dempsey]

I am wondering if I am using flash fill properly.

In Tv or Av modes, if you set the 550ex to high speed sync, then is that considered flash fill, as in if I am shooting birds zoomed out at 400mm and then are 50 feet away, and I have my shutter set to a 350 and my aperture a f/8... the flash will fire and the picture will just have shadows slightly filled, correct?

Or is there another method of using flash fill? I presume you need to set it to high speed sync or else your stuck below a 200 shutter correct? The way I am understanding it, is that I set my camera to whatever I would without the flash, and then if I add the flash it's just an added little light in the shadows, if I am doing this in daytime or adequatley lit places?

If someone wants to help me out on flash fill usage, I'd appraciate that. thanks!

[Sebastian]

I am wondering if I am using flash fill properly.

In Tv or Av modes, if you set the 550ex to high speed sync, then is that considered flash fill, as in if I am shooting birds zoomed out at 400mm and then are 50 feet away, and I have my shutter set to a 350 and my aperture a f/8... the flash will fire and the picture will just have shadows slightly filled, correct?

Or is there another method of using flash fill? I presume you need to set it to high speed sync or else your stuck below a 200 shutter correct? The way I am understanding it, is that I set my camera to whatever I would without the flash, and then if I add the flash it's just an added little light in the shadows, if I am doing this in daytime or adequatley lit places?

If someone wants to help me out on flash fill usage, I'd appraciate that. thanks!

Sean,

First, flash fill and high speed sync are two completely different things.

Flash fill is simply using flash to fill in shadows to bring out detail. Now if you need a high shutter speed to expose properly, then high speed sync would be on, but it does not make the flash "flash fill." The fact that you're using flash to fill in shadows makes it flash fill, no matter what modes you're in.

Now, all you need to do to use flash fill is turn the flash on. Then just like any other time, the camera will put out enough light to properly expose the subject. But since it is also exposing for the ambient light, you get a balanced exposure.

Now the Canons do something that's sort of unclear, they try to automatically apply fill-flash reduction to make it appear more natural when flash is being used as fill-in. Few people know how it does this, but it's not very predictable, and can give unexpected results. The best way is to turn off the auto fill-flash reduction (it's custom function 14, page 150 in the manual) and use the flash just like any other time, except with a flash exposure compensation to reduce it's output. I like -1.5 personally, but others have different values that they like. Basically, you're telling the flash to put out enough light to underexpose by 1.5 stops under the "proper" exposure. That reduces the obvious flash look, and still does a great job at filling in shadow detail and creating catchlights in subject's eyes.

[Sean Dempsey]

That is very interesting.

So I set the 10D to not use compensation, I get that. And now when I am using it for a "fill", I manually set the 550ex to -1.5? That makes sense.

The question I had about high speed syncing was for when my subject requires it, OR since the flash is so fast, do most shots that would normally need a faster shutter speed be fine at 200 since the flash is so fast, the shutter speed at that point only really affects the background and ambient lighting? So if I wanted to do a major league batter swinging, I could use a 1/2000 without a flash and get a frozen shot, or use 1/200 with a flash and get a flashed shot, or if I used a 1/2000 with a flash, I'd get the batter lit up and the background very underexposed?

[kafin8ed]

I wish the high-speed synch was that good Sean. When you operate in high-speed synch mode the distance that the flash will reach is dramatically reduced. I heard somewhere that it's like 10 feet. I have had very little luck using a high-speed fill when shooting mountain bikes because they are rarely close enough to you to get in the flash range. My best luck has been using it when shooting wide or fisheye and litterally holding the camera up to the subject (not looking through the viewfinder) that way I get the flash close enough without getting run over. High speed synch with a tele lens? I haven't had much luck with it above 1/200. Lately I've been having a great deal of luck panning under the synch speed with the 10D/550ex combo, even with a long lens, but that doesn't work for everyone.

[Sebastian]

Sean,

Like Alan already mentioned, the distance is VERY short in high speed sync. The flash has to pulse many times to be able to cover the entire frame, and each pulse is very weak. Therefore, the distance and power output are drastically reduced.

The high-speed sync is meant for when you need to use a wider aperture or do need slightly faster shutter speeds to stop action. It is not meant to be able to go anywhere on the shutter speed range and still have regular flash output.

[Sean Dempsey]

Okay that all makes sense.

Part of my question is in regards to this picture of Moose Peterson using the Better Beamer flash extender:



Since it looks like he's using a 600mm, I was wondering what sort of application the flash would have when doing wildlife and such. I am gonna buy one of those extenders, they are like 30 bucks, and was curious how to use it to use flash fill when doing wildlife.

you guys answered alot of my questions

[Mike Platts]

He's on a tripod, so he may be under 200.

I have not had any luck with high synch at over 10 ft. either. I've tried it for outdoor weddings etc. It does not give a full burst just a bunch of mini bursts for as long as the shutter is open. The faster the shutter, the less light from the flash. Atleast this is my experience.

Mike

[paulnj]

to use fill WITH an extender is FAR DIFFERENT than without ;)

With a BB set the output to a lower value(-2EV?) AND SET THE FLASH TO THE 50MM SETTING so it recycles faster I use -.7ev as my normal flash setting and adjust from there but with a BB iI set it to -1.7 for close subjects and ADD power as my subjects distance drom camera increases.

[Sean Dempsey]

What do you think of the better beamer?

[paulnj]

the BB is a VERY useful tool if......

you shoot from a TRIPOD using a 300mm + lens(like a 500f4IS).


I hardly use any of my extenders( have one for the 550EX and SB28) due to it's size and my shooting style.I STALK BIRDS like a cat usually and the BB gets caught on bushes. BUT, when I blow the dust off of my tripod.. out comes the BB(even if I don't mount it)

The BB is essentually a magnifying glass infront of your flash...... the sun hitting it for a while (at the right angle) can AND WILL burn a hole in the flash. It happened to A Morris and a few others from what I've read, but NOBODY I personally know.

[mn shutterbug]

Is a flash bracket the only way to get away from white eye in the birds? (similar to red eye in people)

[another view]

Happy (almost) 5th anniversary to this thread...

Still, this part of it doesn't change by technology. There are angles involved, to the point that the only way a bracket (such as a Stroboframe) would help would be if the bird was literally within a few feet. If you don't want the white catchlight (which a lot of people do want), to get the angle far enough between camera and light source you'd need a huge distance in feet between camera and flash.

[Sushigaijin]

Is a flash bracket the only way to get away from white eye in the birds? (similar to red eye in people)

Have you tried off-camera flash? It won't work well for in situ shots, but you can put a flash on a tripod near a bait station/bait perch and wait for something to land...