Why are these shots so different?

Snapper

I'm doing some experimenting in flash technique, with a lot of the information I've gained from these forums - thanks so much to all the learned folk who are passing on their knowledge.

These shots were taken with my Nikon D80, 50mm lens, 1/125 at f1.8.

I had an SB-800 speedlight behind and to the left of me, TTL mode, pointed up at 45 degrees for ceiling bounce. On-camera flash switched off and in commander mode.

I'm just wondering why the flash looks so different on these shots, considering they were both taken in the same place with the same settings within half a minute of each other.

The first shot (2 people) looks great. The second shot (1 person) looks much starker, almost like on-camera flash, and has a very noticeable flash shadow on the right of the photo - looks like her shoulder.

Anyone have any ideas why the difference?



---Ian

Nikolai

FWIW, #2 subject is much closer to the camera/flash location, hence it got much more of the direct flash light.

HTH

S. Horton

^^ Makes perfect sense......

Just by chance, was there a light fixture above you, one that you may have bounced the flash off of on the 2nd shot, not the first? She seems filled on the left somehow. (Door frame, extra light on it not on shot #1)

Snapper

Nikolai wrote:

FWIW, #2 subject is much closer to the camera/flash location, hence it got much more of the direct flash light.

I probably moved closer to the subject, but the flash was immobile on a shelf behind me, and the subject didn't move any closer. Flash to subject distance was the same.

S. Horton wrote:

Just by chance, was there a light fixture above you, one that you may have bounced the flash off of on the 2nd shot, not the first? She seems filled on the left somehow. (Door frame, extra light on it not on shot #1)

Ambient light was just the same. Bare ceiling above.

I have to say, after more flash experimenting tonight at an informal dinner, that I have yet to get predictable results with the D80 in Commander mode and the SB-800 off-camera in TTL mode, or even manual mode. Fresh batteries. Just hand-holding the SB-800 to the left or right of me at arm's length, pointing at the subject (because the ceiling was high and painted blue).

Sometimes I get a completely black frame, sometimes it's fine, sometimes it's wildy over exposed. I guess it must be operator error, but it's very frustrating not being able to nail the same lighting shot after shot.

At the moment I can't imagine how folks use a hand-held SB-800 at, say, a wedding reception and get usable shots time after time. I must be making some fundamental error, but I've studied the threads here and sites like Neil van Niekerk's in depth and I can't see where I'm going wrong.

digismile

Ian,

I don't use Nikon gear, but I do this same kind of shot very frequently with my Canon gear and I do get consistent results.

I looked at the exif of the two shots and I'm curious about the Flash info. It says: "Fired, strobe return light not detected, auto mode."

Is this the normal message for TTL mode? All the light evaluation is supposed to happen a split second before the actual shot via communication between the camera & flash.

I wouldn't expect to get overblown images if the TTL was working.

Snapper

digismile wrote:

Ian,

I looked at the exif of the two shots and I'm curious about the Flash info. It says: "Fired, strobe return light not detected, auto mode."

Is this the normal message for TTL mode? All the light evaluation is supposed to happen a split second before the actual shot via communication between the camera & flash.

Yeah, I've wondered about that myself. It seems if I use the on-camera flash it says "strobe return light detected" and if I use the flash off-camera in Commander mode it says "strobe return light not detected". This is consistent so I assume it's correct.

In a "controlled" situation (camera on tripod, flash on stand, shooting a teddy bear) I get consistent results as I change aperture/shutter speed/ISO/ambient light, so the system IS working. It's in "shooting from the hip" situations where I have trouble, which makes me assume it's operator error. Perhaps the flash hasn't fully recharged between shots? I'm not sure if the camera will let me take a shot if the flash isn't charged - will have to look it up.

dangin

i shoot nikon and a couple of possible scenarios come to mind:

1) flash wasn't fully charged on first shot
2) your camera metered just slightly different and CLS figured it should pop a little stronger flash than in image #1

i know i'm going to have some naysayers after i make the following comment, but in my mind, and the minds of other shooters i know:

nikon CLS (w/ TTL) sucks.

there, i said it... CLS/commander mode (w/ TTL) is too unpredictable in my book. if you want consistent wireless flash results:

1) use CLS/commander mode sparingly with manual flash modes - must be indoors, have a short distance, and in the same room
2) get pocketwizards and shoot in manual flash modes

also, i'd recommend using either the flash preset white balance or custom white balance. keeping constant exposures using on-camera flashes can be tough sometimes.

Snapper

dangin wrote:

i shoot nikon and a couple of possible scenarios come to mind:

1) flash wasn't fully charged on first shot

I have other shots that turned out well like the first one.

dangin wrote:

2) your camera metered just slightly different and CLS figured it should pop a little stronger flash than in image #1

I suspect that's it. I did move a little closer. Those background shadows are still kinda weird though - there's no hint of them in the first shot.

dangin wrote:

nikon CLS (w/ TTL) sucks.

Hah! To me it's more like a naughty child: keep your eye on it and it's fine, but turn your back for a second...

LiquidAir

I have always wondered why people use a 45 degree angle for a ceiling bounce. You are looking for diffuse scatter rather than a reflection, so you actually get more bounced light if you point the flash straight up. A 45 degree angle is low enough that you will often get some direct light mixed with your bounce and that is most likely what is causing your shadows and harsh light.

Generally I prefer pointing the flash directly at the ceiling and getting it far enough back that I get bounced light into the eyes. If I can set that up, I usually don't bother with any kind of fill. If the flash is too close to your subject (or the ceiling is high) you will get raccoon eyes and need to use something for fill. Usually in those situations I'll use somthing akin to the better bounce card rather than tilting the flash. Even then, the fill needs to be handled with care to keep the light from looking flat.

Snapper

LiquidAir wrote:

Generally I prefer pointing the flash directly at the ceiling and getting it far enough back that I get bounced light into the eyes.

Thanks Liquid - I'll experiment with your method too. What about pointing the flash straight up and also extending the bounce card, or extending the bounce card and fixing a larger white card to it, in order to direct some flash forwards for the eyes?

LiquidAir

Snapper wrote:

Thanks Liquid - I'll experiment with your method too. What about pointing the flash straight up and also extending the bounce card, or extending the bounce card and fixing a larger white card to it, in order to direct some flash forwards for the eyes?

Here is a sample shot with just a ceiling bounce and no direct light at all:



Generally, I start without the bounce card and chimp a shot. If I think the shot needs fill, I then grab my bounce card. Remember that the bigger the card you use the more fill you get. For many situations where I do want some direct light an area between 1" square and 2" square is all I want. Any more overpowers the bounce. I have been tempted to experiment with a dark gray bounce card so I can get a larger fill light without overpowering my bounce. All that said, it is most important that your main light be soft because that is what is creating your shadows. Lowering the power of your fill by keeping your bounce card small lets the ceiling be your main light which is usually what you want.

I find that when I have the flash off camera I can almost always find a placement that works without a bounce card. When I have the flash on camera the flash is often closer to my subject so I usually put a small bounce card on the flash and adjust its size to fit the needs of the shot. Currently the only time I use a large card is when I can't bounce off a wall or ceiling so have to soften the direct light.

Edit: If you are shooting in a studio environment where the light is strictly controlled, you absolutely need to plan for your fill light or your shadows will be too dark. However, in most of my makeshift lighting for candids, the light is not nearly so well controlled and it is often hard to get any shadows at all because your flash lights up the whole room. The the shot above, some of the fill is coming off the table. Also, my bounced flash is fairly close to a wall so I am likely getting some lower angle light that way. More often than not, I find my trouble is too little lighting contrast rather than too much. As a result I normally start without a bounce card and work from there.

bham

Snapper wrote:

I suspect that's it. I did move a little closer. Those background shadows are still kinda weird though - there's no hint of them in the first shot.

With a flash you are going to have shadows, in the first I they are just hidden.