How to balance ambient

[peihmal]

Hi guys,
I need help with how to balance ambient/flash....
I read on Strobist.com and he talks about balancing ambient/flash... I quite don't get how he set it up...
Any input is really appreciated....

[yogestee]

Here is what I do.. I use manual on the camera and set my flash to ETTL.. I take a metre reading of the subject and use that.. Chimp and adjust the Flash Exposure Control accordingly.. If you are too close to the subject the subject may blow out.. For rooms etc you will rarely have to adjust your FEC..

[Curtis N]

Meter the ambient reading first. Decide how you want to expose the background, which will not get help from the flash. You might even take a few test shots without flash. Manual mode generally works best for this. If you want to maximize the range of your flash or reduce recycle time, start with your shutter at X-sync speed and adjust your aperture to get the exposure right.

Then add the flash. You can use E-TTL, you can use the strobist (manual flash test, chimp, adjust) method, or you can use a flash meter. Different situations call for different approaches.

[peihmal]

Thank you guys for the help....
But since I don't have a meter, how can I get reading...Just adjust speed and aperture accordingly to the scene? Is it the meter bar in the viewfinder?
Thanks again for your big help....

[Titus213]

Use the meter in your camera for ambient readings.

[peihmal]

Use the meter in your camera for ambient readings.


Sorry for being so stupid:) but how do I use that, would you mind tell me how... I have 40D
Thanks so much..

[krb]

Sorry for being so stupid:) but how do I use that, would you mind tell me how... I have 40D
Thanks so much..
Put the camera in M, look through the viewfinder and half-press the shutter button.

[Mchu86]

Since you're reading strobist, I'm assuming you're going to be putting the flash off-camera. If that's the case, there's no need to worry about E-TTL, IMO. Use manual on both the camera and flash. It'll give you the most flexibility and control of what you want to do.

Secondly, I found that this post in Lighting 102 to be more helpful than the post in Lighting 101 about balancing flash/ambient, as it's a bit more in-depth and step-by-step: http://strobist.blogspot.com/2007/09/lighting-102-33-balancing-flashambient.html (if you missed it).

[peihmal]

Thank you so much for your help...
Actually I was reading on Strobist blog but haven't got that far yet...

[viet]

Thank you so much for your help...
Actually I was reading on Strobist blog but haven't got that far yet...

How about reading your camera manual first? and this is not meant to be condescending. Your manual will explain to you the differences between metering modes for your camera, in this case, ambient. Then you augment it with flash, start at the lower end of your flash power then increase it till the foreground (your subjects) and the background are about equal, then play with it to taste.

FYI, TTL just means Through The Lens, it has nothing to do with metering modes. It only means the camera is smart enough to look through your lens and use one of the metering modes to determine your exposure.

Your 40D, I assume, can do spot, average, matrix or whatever fancy term Canon came up with, and central average. Depending on how you want your shot to look, pick one. For what I shoot, I use spot at least 90% of the time.

[Titus213]

The meter reading is the bar and hash mark at the bottom of the viewfinder. In manual mode you can adjust both the f-stop and shutter speed, both of which will move the meter reading left or right. Again, in manual mode you can set the exposure level to what you want using the meter - over or under expose as much as you want - or center for normal exposure. On the 40D the meter will only read the ambient light.

[SYS]

To see the flash/ambient light interact, there's nothing like actually trying it. Here's a simple illustration (under typical evening inside your own home with your lamps or whatever lights you use on):

-- Set your 40D to Manual mode and the shutter speed to 1/250sec which is the 40D's max sync. Set the ISO to anywhere between 200 to 400. Choose the aperture to anywhere from f/2.8 to f/5.6.

-- Set your flash to ETTL

-- Shoot some subjects with the above setting

-- Now, change the shutter speed to 1/60sec or 1/30sec and shoot the same subjects and see how much the ambient light came into the scene as opposed to the original setting above at max sync speed of 1/250sec that totally dominated the ambient lights.

There's nothing like visual learning when it comes to how light works....

[peihmal]

Thank you so much for your help...
Those info really helpful for me...
I will try it tonite at home and let you guys know the result....

[René Damkot]

Simply put (assuming the flash is in manual mode (constant light output)):

Flash exposure is controlled by:
Flash power (duh)
ISO
Aperture


Ambient exposure is controlled by:

Amount of ambient (duh)
ISO
Aperture
Shutterspeed


So; you can vary total exposure by altering ISO or aperture, and ambient to flash ratio by altering just shutterspeed.

[Curtis N]

Flash exposure is controlled by:

Flash power (duh)
ISO
Aperture
4. Distance from light to subject.
It's important to remember this, because often the easiest way to adjust the flash exposure is to move the light. You can also change the ratio of subject:background exposure by moving the light.

[René Damkot]

True, that's why I said "Simply put".

I used "flash power" to encompass
Power setting on the flash
Light modifier used
Distance between flash and subject.


"Flash Power" was probably a bad choice of words. ;)

[wcameron]

Here's a way to get a quick test with on-camera flash. Using Manual gives the most flexibility and that's why most of the pros really prefer it to other modes. However there are other ways to learn to balance existing and on-camera flash.

If you set your camera to Tv (shutter priority) or Av (aperture priority), your camera will do many of the calculations for you.

As an example, in Av mode, you can set your aperture to f5.6 or f8 and the camera will select an appropriate shutter speed (up to the maximum sync speed). The meter will ONLY measure the available light so the exposure of your scene will be calculated automatically. Once you turn on your flash, the camera and flash will work together to adjust the flash output to properly expose the foreground subject (say Aunt Millie) while leaving the actual exposure (shutter speed and f-stop) unchanged for the existing light.

If you're doing this indoors, you will likely notice that the shutter speed will be very slow due to the limited existed light. If you're hand holding, pump up the film speed to 600 or 800 and you may get a better shutter speed.

Depending on the light source hitting the background, you may see that it takes on a very yellow tint. This is due to your flash putting out daylight balanced light while the background is lit by incandescent which records somewhat yellow. If this bothers you, you can set your white balance on tungsten and place a filter over your flash to make the light from your flash match the color of the artificial lighting.

Once you have an understanding of how the foreground and background lighting work together, you can begin to work towards using your camera on manual.

I hope this helps.

[sfaust]

Here is the technique I teach in my workshops.

http://stephenfaust.wordpress.com/2008/07/05/strobe-and-sunlight-how-to/

[SYS]

Here is the technique I teach in my workshops.

http://stephenfaust.wordpress.com/2008/07/05/strobe-and-sunlight-how-to/

For a second I thought the the scantily clothed woman had a Pelican case with her... :D

Nice tutorial, thanks.

[alabama1980]

Here is the technique I teach in my workshops.

http://stephenfaust.wordpress.com/2008/07/05/strobe-and-sunlight-how-to/

you my friend are awesome. im one of those that needs to hear things a certain way sometimes before it clicks. i've been struggling with this since i got my studio lights, and i never could grasp it. thanks to the OP for asking the question, and you for a great response on your blog.

[sfaust]

you my friend are awesome. im one of those that needs to hear things a certain way sometimes before it clicks. i've been struggling with this since i got my studio lights, and i never could grasp it. thanks to the OP for asking the question, and you for a great response on your blog.

Glad to hear it clicked, since it means all the time I spent on my blog was not wasted ;)