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View Full Version : Fill flash clarification sought



Dean Ingwersen
02-25-2008, 07:04 PM
Hi all,

I'm a little embarrased to ask this question as I'm sure the answer is quite obvious, but here goes...how do you use fill flash at a shutter speed faster than the sync speed of the flash? I've seen some images here where the shutter speed is way over the 1/250 sec sync speed of my 580EX II flash, but I can't work out how to do it on my camera:o. Any advice greatly appreciated.

FWIW, I generally operate in AV mode when photographing stuff...and the reason I'm asking is related mainly to removing shadows in sunny conditions (e.g. undersides of raptors, small birds in shadows in woodlands, etc).

Thanks.

Alfred Forns
02-25-2008, 08:19 PM
Hi Dean Just put the flash in high speed sync For a 580 there is a button on the top that cycles through normal HS and rear curtain

Remember you will loose a lot of light with high shutter speeds at 1/500 is half !!!!

Maxis Gamez
02-25-2008, 09:05 PM
I use fill flash. I set my 550EX to "H" (high speed), ETTL and depending on the amount of light I need, I make chances to the flash. I set my camera 90% of the time to MANUAL.

Dean Ingwersen
02-25-2008, 10:42 PM
Thanks Al and Maxis. Just as a point of clarification I attach this image of a male Crested Shrike-tit...not a great photo, lots of faults so please don't critique it. What I'm trying to work out is how I use fill flash to lessen the shadows on the bird from things such as poor light angle and surrounding vegetation, with a shutter speed (set via AV mode) that's faster than 1/250sec.

Image taken with Canon 20D with 500mm f/4 and 1.4x TC, ISO 100, f/5.6, AV -1/3, 1/500 sec.

Alfred Forns
02-25-2008, 11:02 PM
It will be tough to eliminate but the flash will work Your easiest way is to set the flash for -1 and fire away Check your display

if you want to go manual Go to full power focus on the bird then read the distance See what is the effective distance of the flash at the settings you are using Most likely you will fall short on light In that case keep in manual and blast

For specific image you are showing my first choice would be to get rid of the shadow in PS Not really difficult !!!!!!!

Dean Ingwersen
02-25-2008, 11:15 PM
[quote=Alfred Forns;40767]It will be tough to eliminate but the flash will work Your easiest way is to set the flash for -1 and fire away Check your display
quote]

So set it to high-speed as you suggested earlier, then for this image I would have dialled in the -1 compensation on the flash, and it should 'keep up' with a shutter speed of 1/500sec? Have I understood you correctly?

Maxis Gamez
02-26-2008, 06:29 AM
Dean,

What Al's is trying to say is to basically do a test image and adjust your flash accordingly.

Read this article.

http://photonotes.org/articles/eos-flash/

I'm sure you will have no questions after. :)

Dean Ingwersen
02-26-2008, 05:31 PM
Thanks heaps Al and Maxis...gave it a go last night and it worked perfectly.

For the information of others, I also found this website:
http://www.rpphoto.com/howto/view.asp?articleID=1026
(http://www.rpphoto.com/howto/view.asp?articleID=1026)
Cheers, Dean

Jared Lloyd
02-26-2008, 05:48 PM
Does anyone know of any good sources of in depth information on flash?
this is something I am trying gain more experience with as well.

David Kennedy
02-26-2008, 06:11 PM
Does anyone know of any good sources of in depth information on flash?
this is something I am trying gain more experience with as well.

One of the best places to learn about flash (almost entirely manual flash, though) is strobist.com (http://www.strobist.com). The guy is a photojournalist for the Baltimore Sun and I've learned a lot about flash from that blog. However, what he's teaching and what you need for wildlife are different. But you'll still learn something cool from that blog.

For on-camera flash for wildlife photography, Artie does talk about it in his CD book. However, even Artie will admit that flash on hi-speed sync is pretty confusing. Especially Canon's flash system, which drives me crazy. I had an epiphany this summer and learned that the only way to get rear curtain sync on Canon is to set it on the camera body and the flash unit. And rear curtain and hi-speed sync cannot be combined.

For the most part, leaving the flash backed off to -2 works for me, but I don't always understand what it's doing. I have a much better understanding of how flash works in manual mode, and again, that's because of the Strobist blog.

David Kennedy
02-26-2008, 06:15 PM
I forgot to mention something that's kind of interesting: apparently, you can trick a Nikon D70 into syncing with the flash at ridiculously high shutter speeds. http://strobist.blogspot.com/2008/01/control-your-world-with-ultra-high-sync.html