Struggling with Flash Photography

[martcol]

OK, I have 1D Mk II (a camera that admitedly, does not reflect the photographer's skill levels) 550 EX and 420 EX and the transmitter. I have tried loads of combinations using Slave/Master set-ups but do not get consistent results. Besides, just going with the 550 EX on camera is the quickest thing and if I could get that good I think I might be content with a few harsh shadows!

In dull conditions (British Winter) do I go for Av, Tv P or M? Av, I get too slow shutter speeds and Tv seems to give shots that look as though they were taken at night (dark background bright subject). I am talking about group, individual people shots out of doors. OK, OK, it's a wedding. My first. I have read all the stuff about reading books, getting lawyers etc. but that just makes me feel more nervous. I have to do this now. I want to do it.

Any direct, but gentle advice will be greatly recieved!

Regards

Martin

[RichardtheSane]

I agree with a lot of what Bloo Dog has said, and what I disagree with is entirely related to the british weather...(Mr B Dog, you are formally requested to become a UK inhabitent as you clearly bring sun 3/4 of the time - today I sprinted to get a shot because I saw the light break briefly! )

Are you indoors or outside?

(please say outside )

[martcol]

Originally Posted by RichardtheSane

I agree with a lot of what Bloo Dog has said, and what I disagree with is entirely related to the british weather...(Mr B Dog, you are formally requested to become a UK inhabitent as you clearly bring sun 3/4 of the time - today I sprinted to get a shot because I saw the light break briefly! )

Are you indoors or outside?

(please say outside )

Much as I would like to say outside, it may be indoors! Funny though, it's the outdoor flash photography that gets me. The long range weather forecast seems to point to a pretty miserable day for Saturday and that's the day! The site for outdoor photos, to make it worse, is a small grass area about 3 or 4 minutes from the church so, nowhere for guests to shelter whilst the photographs are being taken.

The church isn't too bad. It's a fairly well lit premises and quite tidy (uncluttered) interior. There's a balcony that might make a good place to stand to take larger group shots too.

As for the weather, Bloo Dog, you may have guru status on the photography advice front and even a tour guide but as an adviser on British weather, (in a nutshell) your a little bit shaky!

There has to be a first time.

Regards

Martin.

[robertwgross]

Hmmm. Dull conditions. British winter.

The only good subject is to shoot the piper who stands out in the church courtyard.

---Bob Gross---

[Tom W]

Originally Posted by martcol

OK, I have 1D Mk II (a camera that admitedly, does not reflect the photographer's skill levels) 550 EX and 420 EX and the transmitter. I have tried loads of combinations using Slave/Master set-ups but do not get consistent results. Besides, just going with the 550 EX on camera is the quickest thing and if I could get that good I think I might be content with a few harsh shadows!

In dull conditions (British Winter) do I go for Av, Tv P or M? Av, I get too slow shutter speeds and Tv seems to give shots that look as though they were taken at night (dark background bright subject). I am talking about group, individual people shots out of doors. OK, OK, it's a wedding. My first. I have read all the stuff about reading books, getting lawyers etc. but that just makes me feel more nervous. I have to do this now. I want to do it.

Any direct, but gentle advice will be greatly recieved!

Regards

Martin

Use Manual - set the aperture for the DOF you want. Set the shutter for the action-stoppage you want. Set the ISo for the light you want. Don't get real dark (f/8, 1/500, ISO 100 is going to really cut your flash range and give you a dark background). Don't get real light (f/1.4, 1/30, ISO 3200 is probably going to overexpose the background unless its really dark - plus, the flash will be less relevent). The E-TTL will do its job for exposure, since it does its own exposure separately from that of the camera. You may have to dial in some +/- flash exposure compensation, but generally, E-TTL II is fairly consistent (but not perfect).

In Av, your camera will try to expose as though there were no flash, which usually means a very slow shutter. In Tv, you'll get the overall exposure that the shutter/aperture provides, but the flash will fire only to expose the main subject (I don't know how it chooses the main subject). Those two modes are best left to non-flash and "creative" shooting.

BTW, I've found that with my 1D-II and 550EX (or 420EX), I consistently have to use +2/3 stops of flash exposure compensation. Occasionally a bit more or less, but nothing like the compensation changes I had to dial in with the 10D.

Oh, and one last thing - don't forget to change modes when you want to work without the flash. Be cognizant of whether you are using the flash or not. The camera won't remember to change from manual to Av for you. I speak from (bad) experience.

[martcol]

I've just nipped out to the garden with my 1d mk II and 420EX. Selected Manual. Shot a few at f8 1/125 and Bingo! Just did it and oomph! Now I have 80 shots of my clean washing blowing in the wind with a rickety fence in the background and a falling-down shed. A real period peice. Nicely exposed (sky's a bit clipped), lots of detail. Colour good. Now if only I could sell these as Stock!

I have always steered clear of Manual. Not now though! Hmmm. Maybe I should shoot that washing again and check out a few different apertures....

Thanks again

Martin

[martcol]

Originally Posted by Bloo Dog

....I think you're oversimplifying things.

Groan....

And there I was, thinking I had it cracked!

When I tested TW's method it worked. What I thought was happening was that I just set aperture/shutter and the Flash (cleverer than me) popped at what it thought was needed. OK so my stock photograph with towels blowing romantically with the wind were a tad underexposed but, I could live with that. Tomorrow I have more time and I will go out and shoot hundreds of even better shots of nothing much in particular.

Til then!

Regards

Martin

[Tom W]

Originally Posted by Bloo Dog

Tom W:

I follow what you're saying but I think you're oversimplifying things.

Shooting on manual requires that you KNOW the existing light level (or at least have some exposure standard) if one wants to balance the light. Somewhere in the mix, the photographer will have to meter, either with the camera's reflective meter or with a handheld incident light meter. If ambient light is not a consideration (as in a very dark church), then the photographer will have to choose a starting point for his exposure when he uses flash.

As far as the balance between background and subject, you are correct. And those should be considerations for your aperture, shutter, and ISO settings. But for proper subject illumination, E-TTL does its own separate flash exposure regardless of the camera settings by metering a short, weak pre-flash. It only cares about how much reading it gets through the lens from the pre-flash and adjusts flash output accordingly. As long as the lighting needs are within the range of the flash's minimum and maximum output, it will emit for good exposure.

My point was (and you're right, I oversimplified it) that the photographer is in charge of exposing the background while ETTL takes complete control of the flash. Using the camera in manual and the flash in auto is a pretty quick, easy way to achieve decent flash exposures. My perspective was from a situation of shooting in a room of people, such as a party or reception. You'd want to do a lot more precise work for posed and studio work.

The shutter speed will determine "the action stoppage" but it will also affect the exposure. Exposing with shutter priority (with the flash set to manual) will allow the aperture values to change. The shutter speed will affect the background lighting ONLY if the exposure values of the aperture and the existing light remain constant and if one uses flash or some other frontal lighting to expose the foreground.

The way that E-TTL and E-TTL II works, using either aperture or shutter priority puts the flash into a "fill-flash" mode. Your shutter and aperture will work for ambient exposure, but you'll suffer with either a wide aperture (little DOF) if you want the shutter fast enough in Tv mode, or too slow a shutter if you set aperture for your desired DOF in Av mode. In manual exposure, you can set both for what you want. The flash will do its job in ETTL.

Use f.8 @1/125 as a starting point (and assume that this is the "proper" reading for your existing light). Your flash would emit f.8 and your aperture would remain at f.8.while your shutter moves at 1/125 second. If you slow the shutter speed to 1/60 but keep the aperture value at f8 (to expose the foreground), then the background will receive one stop more light than the foreground, thus the background will be 2x brighter than when it was exposed at 1/125. The shutter speed will begin to affect the exposure of the subject when it allows the existing light exposure to exceed the flash exposure.

If the photographer uses the ISO setting to "get the light you want" that' COULD create major problems, depending upon which mode the photograph is exposed in. All things being equal and unchanging, f.8 @ 1/125@ ISO 100 will provide the same relative exposure as f.8 @ 1/125 @ ISO 400, etc.. When the other values change( existing light,shutter, aperture) then so does exposure.

f/8 @ 1/125 ISO 100 - if you increase ISO by 2 stops, you've either got to speed up the shutter by 2 stops, or close the aperture by 2 stops or some combination.

I understand what you are saying, and it's a brilliant set of approaches and solutions. I can tell that you are a quick thinker and are accustomed to working on-the-fly.

Quick thinker? Quick enough to leave home without my wallet half the time.
Actually, I studied this odd flash system rather slowly, and I still don't get the entire scheme. With Canon's E-TTL, you don't control the flash, it controls you.

I had to stop to think about what you told me. Your suggestions work well for the savant, but those of us who are more idiot than savant (i.e., ME) might get into trouble with it.

In a Nutshell,

Bloo Dog

"No matter what I do, it always feel better when I stop doing it." (Dogbert)

[Tom W]

I forgot to mention the EOS E-TTL bible:

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

[gmitchel]

For flash shots, I typically use M with a Canon DSLR. They have E-TTL or E-TTL II.

Those slow exposures using AE result from the camera metering for ambient light. If you use flash as the only source of illumination, you pick your aperture/shutter speed combination with Manual (M) mode and let E-TTL or E-TTL II handle the flash exposure.

That's how nature photographers shoot butterflies without a tripod and wide DOF. As long as you are within the range of the flash, E-TTL or E-TTL II will properly expose the subject.

Flash falls off at the inverse of the square of the distance. Flash only illumination can result in a dark background even for a brightly-illuminated subject. If you need more background illumination, you can either place a second flash closer to the background or you might want to use AE and a slower exposure or wider aperture to get more ambient background illumination.

Cheers,

Mitch