Few questions about flash. Just getting started!

[Tobiah]

Any help gladly accepted no worries if you havent got time to help. I know theres lots of info and i've read lots of sites this week...

So i've been trying to figure out how to use my new 580ex II aquired this week...

things ive discovered so far...

1) Wider Aperture (lower f number) increases the amount of light and decreases the amount of flash needed)

2) The Flash white balance setting is giving me the most natural settings , and ive read that this setting is best at shutter speeds over 1/199 (shutting out nearly all ambient light) (I DO Shoot in RAW so this is not too much of a problem?)

2a) With me shooting in RAW shall i just leave AWB on and worry about the colour temp in my Processing? (That wouldnt bother me if results same,would like to keep chopping and changing different parameters down as much as poss)

3) In what situations would i be best to cut out ambient light?

4) If using ETTL (which i think will be best for me for now...) how do i know how much FEC (+/-) to include for the shot?

4a) When bouncing how much FEC will i need to add or take or will it figure it out?

(Im going to a fancy dress party tomorrow so will be shooting peoples photos. Bouncing may not be alwas an option and i'll be walking around)

I'd like not to have to take more than 1 photo per person would ETTL with 0 compensation in Aperture mode be best? or tv mode and set for ambient light amount?

Thanks for trying to make sense of this! MUCH APPRECIATED!

[Curtis N]

1) Wider Aperture (lower f number) increases the amount of light and decreases the amount of flash needed)
Correct. Raising the ISO does the same thing. But E-TTL will account for those changes, theoretically.

2) The Flash white balance setting is giving me the most natural settings , and ive read that this setting is best at shutter speeds over 1/199 (shutting out nearly all ambient light) (I DO Shoot in RAW so this is not too much of a problem?)
When the flash head is pointed forward, the flash reports the color temp info to the camera and the camera will use this with either Flash or AWB white balance setting. If you're bouncing or including ambient light then Flash WB setting may not be best. AWB and RAW is the best combination so you can adjust the WB only on the shots that need it.

3) In what situations would i be best to cut out ambient light?
Fluorescent lighting sucks. Tungsten light doesn't suck but it has a very different color temp than flash so I try to obliterate it when conditions allow. When you eliminate the ambient, the images will look "flashed" with dark backgrounds unless you bounce off the ceiling.

4) If using ETTL (which i think will be best for me for now...) how do i know how much FEC (+/-) to include for the shot?
Only practice and experimentation can help you here. With flash as your main light, maybe start at +2/3 FEC. Adjust up for subjects with significant amount of white, and down for subjects with a lot of black or dark colors.

4a) When bouncing how much FEC will i need to add or take or will it figure it out?
Typically a bit more +FEC is required when bouncing because the brighter backgrounds produced by this technique affect the metering (my theory, anyway).

For your fancy party, the big question is how high is the ceiling? If it's 8-12 feet you should be able to bounce for all your shots.

Use Manual mode on the camera. Av and Tv are likely to lead to frustration. Read this thread (http://photography-on-the.net/forum/showthread.php?t=177622), and practice.

[In2Photos]

My answers are in red but check out this thread for more help too.
http://photography-on-the.net/forum/showthread.php?t=138907

Any help gladly accepted no worries if you havent got time to help. I know theres lots of info and i've read lots of sites this week...

So i've been trying to figure out how to use my new 580ex II aquired this week...

things ive discovered so far...

1) Wider Aperture (lower f number) increases the amount of light and decreases the amount of flash needed)
Yes, wider apertures will more ambient light. The output of the flash will also decrease, saving batteries and shortening the recycle time, or it can enable you to illuminate something farther away if needed.
2) The Flash white balance setting is giving me the most natural settings , and ive read that this setting is best at shutter speeds over 1/199 (shutting out nearly all ambient light) (I DO Shoot in RAW so this is not too much of a problem?)
The flash setting is optomized to the flash's color temp. But the shutter speed does not necessarily have to be that fast to shut out all ambient light. If there is little ambient light t begin with a smaller aperture and lower ISO combined with a slow shutter speed could still produce a "correct" WB. For instance, if I only have an overhead light with a couple 40 W bulbs the room will be dimly lit. At ISO 100 and f/8 I could probably use a shutter speed of 1/15 or 1/30 and not catch much ambient light.
2a) With me shooting in RAW shall i just leave AWB on and worry about the colour temp in my Processing? (That wouldnt bother me if results same,would like to keep chopping and changing different parameters down as much as poss)
I leave mine on AWB as it seems to do fine indoor with flash. Especailly since I shoot RAW and can batch an entire set of photos for WB with a click or two. Plus I usually forget to set it back. ;)
3) In what situations would i be best to cut out ambient light?
When you don't want it. The saying "Does it add anything to the photo?" applies to everything, including ambient light. If the ambient light doesn't add to your photo then use the appropriate settings to minimize or eliminate it.
4) If using ETTL (which i think will be best for me for now...) how do i know how much FEC (+/-) to include for the shot?
This is very subjective and just like anything takes practice to figure out. There is no exact settings. Take some test shots and see which works best for you.
4a) When bouncing how much FEC will i need to add or take or will it figure it out?
Check the histogram just like you would when taking a shot with ambient light. But also evaluate the scene. If there is lots of reflective or bright surfaces in your scene you will likely need to add FEC just like you need to add EC for taking photos of largely white or bright scenes.
(Im going to a fancy dress party tomorrow so will be shooting peoples photos. Bouncing may not be alwas an option and i'll be walking around)

I'd like not to have to take more than 1 photo per person would ETTL with 0 compensation in Aperture mode be best? or tv mode and set for ambient light amount?
This depends on how much ambient light is available. If there is little ambient available Av might yield some very low shutter speeds, causing motion blur or camera shake. Can you go early to the party and try some test shots, maybe of the wait staff, or a friend or assistant? If the lighting is consistent use M mode, set your aperture and shutter speed and increase the ISO until you get your desired level of ambient light. Take a couple shots and then adjust the aperture and shutter speed to compensate for DOF and motion blur.
Thanks for trying to make sense of this! MUCH APPRECIATED!

[Tobiah]

Ive always been under the impression that for pictures of ppl often its good to keep aperture low (like 2.8 for nice bokeh) but im reading with the flash for general guidelines f4 for people and f8 for groups? is that good advice?

also if i change my aperture in manual mode (in ettl on flash) the flash will auto adjust itself for all my settings and i just have to say whehter i want its auto to be brighter or darker?

Thanks for all your help guys! i really am reading and re-reading eveything!

[In2Photos]

Ive always been under the impression that for pictures of ppl often its good to keep aperture low (like 2.8 for nice bokeh) but im reading with the flash for general guidelines f4 for people and f8 for groups? is that good advice?

also if i change my aperture in manual mode (in ettl on flash) the flash will auto adjust itself for all my settings and i just have to say whehter i want its auto to be brighter or darker?

Thanks for all your help guys! i really am reading and re-reading eveything!
That depends on your intentions. If small DOF is what you are after then yes keep your aperture at say f/4. But DOF is more than just aperture. It is a combination of focal length and distnace to subject as well. The flash will adjust if you change the aperture. ETTL uses a pre-flash fired just before the shutter opens to calculate the actual flash needed during the exposure.

I wanted the background here to disappear.
f/4, 70mm, 1/100, ISO 100 bounced with a StoFen diffuser.

http://www.pbase.com/madawson/image/69498799.jpg

But here I didn't need the background to disappear and I wanted to keep my shutter speed down below sync speed.
f/11, 50mm, 1/160, ISO 100, straight on, no diffuser (probably a little hot too but I like it)
http://www.pbase.com/madawson/image/77034274.jpg

[Tobiah]

so no lower than f4? like not f2.8:?

[Curtis N]

You can shoot portraits at any aperture you want. But an understanding of depth-of-field will help you make a better choice.

As a general rule, you can shoot an individual portrait at f/2.8 if it's not a really tight shot and if you focus perfectly on the eyes.

But when you're shooting couples or small groups, it's often better to stop down a little for more DOF since not everyone will be the exact same distance from the lens. A smaller aperture will also mask minor focusing errors and give you a better keeper ratio in that regard.

[In2Photos]

so no lower than f4? like not f2.8:?
I can't say it any better than Curtis usually does and this time is no different. The only thing I would add is that some people like to take portraits with very small DOF. Often we see examples of a portrait where one eye is in focus and the other is not. Is it wrong? No. But some like it and some don't. Like Curtis said larger apertures are less forgiving so you have to nail focus for it to "work".
You can shoot portraits at any aperture you want. But an understanding of depth-of-field will help you make a better choice.

As a general rule, you can shoot an individual portrait at f/2.8 if it's not a really tight shot and if you focus perfectly on the eyes.

But when you're shooting couples or small groups, it's often better to stop down a little for more DOF since not everyone will be the exact same distance from the lens. A smaller aperture will also mask minor focusing errors and give you a better keeper ratio in that regard.

[Tobiah]

good point. thanks for the advice guys ill post some shots in the people forum. im not doing it for money just for fun at the weekend. im in the band playing for about 120 people so thats my main concern for the night...

What mode would you leave it in for my non camera savvy girlfriend to take photos of the band? Thanks

[In2Photos]

good point. thanks for the advice guys ill post some shots in the people forum. im not doing it for money just for fun at the weekend. im in the band playing for about 120 people so thats my main concern for the night...

What mode would you leave it in for my non camera savvy girlfriend to take photos of the band? Thanks
P Mode. That way you still get the benefits of RAW but still all auto for her.

[Tobiah]

yeh thanks. im thinking setting it up in between a couple of songs for some second curtain flash shots for some cool effects...

maybe like .3 seconds or something? then ask her to switch between m mode and p mode...?