TTL - What were those settings?

Hi gang,

New to the forum here as a poster, but have lurked around for a while. I tried searching for the answer myself, but didn't have any luck so thought I'd post for the first time!

I've struggled with how to phrase this question, so I apologize if it is wordy. Here goes:

I like TTL for the main reason that I can spot meter on a subject's face and be pretty confident that the portion of the face I locked on is going to be exposed correctly. I can glance at the histo to know that everything else is in order and I'm good to go.

However, I like the full manual (non-TTL) because it is repetitive, predictable, and consistent. The only problem is I can glance at the histo to see if there are any issues with the overall image, but that doesn't always tell me if the face is properly exposed. In other words, I don't always know in that histogram where the midtones of the face fall. So, I can go through several shots and realize later in post-processing that I was off slightly on the face exposure. Now I have a bunch of pics to tweak.

Here is what I would prefer to do: Chimp a shot in TTL. If I like the results, I flip the strobes over to manual and dial in those settings. Now I have those settings consistently on every shot.

The only problem is: After I have just taken a shot using TTL, how do I know what those strobe settings were? It doesn't appear to show them on the back of the LCD (SB-700). Or maybe it does and I'm just overlooking it.

Could really use some advice here because it seems like it would make this process so much easier.

well as we dont know what camera you have we dont know if its TTL or iTTL......your data will be in the EXIF here ....sounds like another read the flash and camera manual ......

Jeffrey's Exif viewer

I don't know if the cameras report flash power level in Exif. I know Nikon does not report it. So, you could use a flash meter (Not on the TTL flash, but you could adjust the manual flash power to the aperture/ISO you want to use). Or you could adjust the manual flash power to be right first, trial and error, watching the rear LCD picture, and sometimes the histogram is helpful.

Spot metering on a face does NOT give "correct" exposure of the face. The goal of any metering is to give you a middle gray result, which is rather different than a "correct" result". The reflected meter is dumb computer that has absolutely no clue what the subject is, or how it ought to be, so there is no concept of "correct". It's rules are different than your goal.

Not at a spot level, but at an overall level, many average scenes do measure about middle, so this sometimes works. But for spot metering, you have to pick a spot that ought to meter about the middle. Spot metering is an advanced technique, it is anything but point&shoot.

If you spot metered on a middle gray card, it probably gives a "correct" result (this may not be precise, but it is definitely ballpark). If you meter on a white card, you surely need to open up maybe a couple of stops to make it be white. If you meter on a black card, you need to stop down a couple of stops to make it be black. If you meter on Caucasian skin, you probably open about one stop.

Perhaps you knew all that and are doing it. You just did not say it that way.

See How light meters work

Trend ..perhaps I missed something ..if its iTTL or TTL its done automatically .....why do you need to know ?? If you think your gun gives over or under exposure then you adjust the flash exposure in your camera. In any case and underexposure is good ..say 1/2 stop then you lift it in your image software .....Please dont go all manual unless you have a fixed studio set up.

When you turn on the flash that sets the shutter to 1/60 so if you are in Aperture mode at F8 then the flash adjusts the duration of its flash to give you correct exposure

Thanks for your replies. Sorry I didn't realize I hadn't mentioned the camera.

It is a Nikon D7000, using 2 SB-700's with pocketwizards. So, it is iTTL.

The face usually is a mid-tone, which is why I spot meter on the face. That's what works for me. But, that's irrelevant. That was just giving some background information on why I would want to fire off a shot in iTTL, then dial in those settings manually.

The crux of the question was: if I just fired off a shot in iTTL, is there any way to know what power the strobe was at? I look at the back of the SB-700's and I don't see it displayed on the LCD. Wasn't sure if it was buried somewhere.

Yeah, this is in a fixed studio setup. Here is my scenario...

My boys participate in various activities...church group, cub scouts, whatever. Often I get asked to take portraits of all the children. No problem. I bring in my backgrounds, set up my lights, ready to rock.

If I do it in iTTL, that's really kind of a mess in post processing. The lighting could be all over the place and I could potentially spend a lot more time editing images individually. It would be much trickier to apply global changes in Lightroom, for example.

If I do it in manual, the lighting will be consistent for all subjects. The histogram will tell me if the overall image is ok, but sometimes it's hard to tell where the subject's face falls in the histogram (on the LCD, not post). So, I would much rather nail it and nail it quickly. That's why I thought of "Chimp it in iTTL, dial those settings in manually." But that doesn't appear to be possible.

It just seems bizarre to me that there doesn't appear to be a way to tell what power the flashes were at.

triedntru said:

It just seems bizarre to me that there doesn't appear to be a way to tell what power the flashes were at.

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There is not a way though. It is not helpful to know for TTL, sufficient that it comes out right. Watching recycle time will tell you roughly if it was near full power or not (important indicator for bounce).

So, you come at it another way. Indoor portraits, ambient is insignificant (hopefully, because it is usually orange). You set aperture for flash power and depth of field, and set shutter speed fast (maximum sync) to control any traces of ambient. You set flash power either with a flash meter, or by trial and error, to make your picture come out like you want it. Trial is easy for one flash, but if using multiple flash, you really want a flash meter, to set the lights up. You can't get there from iTTL.

IIRC, when you do spot metering on camera, the Flash meter will meter center weighted average.

Only when you use matrix metering on camera, do you get the more advanced TTL-BL mode.

You need to understand that for Flash, the Flash meter and the camera meter are 2 separate metering systems.

daredevil123 said:

IIRC, when you do spot metering on camera, the Flash meter will meter center weighted average.

Only when you use matrix metering on camera, do you get the more advanced TTL-BL mode.

You need to understand that for Flash, the Flash meter and the camera meter are 2 separate metering systems.

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The last sentence is very correct, two very different metering systems.

You also get TTL BL in Center Metering mode. Only Spot metering switches to TTL. Some flashes (SB-700, SB-400, internal flash, and commander/remote flashes) can only select TTL BL mode (except Spot metering of course). The Exif shows this flash mode, if you have a reader that will access it (not Adobe, but the standalones, like PhotoME).

But the TTL flash metering is always in a central zone, it seems not to move. Metering in Matrix mode, yes, the focus spot is dominant to metering ambient, regardless where it is moved, ambient metering goes with it. But in any mode, TTL flash always meters a central zone, my notion is it is intermediate in size between Spot and Center metering, regardless of mode.

I try it this way: Put a large dark or black area in the center of a huge white or light frame area. Adjust focus sensor well off the left side (on white), or well off the right side (on white), vs. in the center (on black). With an ambient level that is negligible to the flash exposure.

There wont be any difference in the flash picture where the focus sensor is, if the same black area remains in the frame center (assuming ambient is low and direct flash distance and focus is kept the same distance, for TTL BL D-lens).

triedntru said:

However, I like the full manual (non-TTL) because it is repetitive, predictable, and consistent. The only problem is I can glance at the histo to see if there are any issues with the overall image, but that doesn't always tell me if the face is properly exposed. In other words, I don't always know in that histogram where the midtones of the face fall.

Click to expand...

Whilst looking at the review histogram page, the one with the white, red, green and blue histograms. Zoom in to the area you want to check. The histogram is of the part you have zoomed into, not the whole image.
Hope that helps.

WayneF said:

The last sentence is very correct, two very different metering systems.

You also get TTL BL in Center Metering mode. Only Spot metering switches to TTL. Some flashes (SB-700, SB-400, internal flash, and commander/remote flashes) can only select TTL BL mode (except Spot metering of course). The Exif shows this flash mode, if you have a reader that will access it (not Adobe, but the standalones, like PhotoME).

But the TTL flash metering is always in a central zone, it seems not to move. Metering in Matrix mode, yes, the focus spot is dominant to metering ambient, regardless where it is moved, ambient metering goes with it. But in any mode, TTL flash always meters a central zone, my notion is it is intermediate in size between Spot and Center metering, regardless of mode.

I try it this way: Put a large dark or black area in the center of a huge white or light frame area. Adjust focus sensor well off the left side (on white), or well off the right side (on white), vs. in the center (on black). With an ambient level that is negligible to the flash exposure.

There wont be any difference in the flash picture where the focus sensor is, if the same black area remains in the frame center (assuming ambient is low and direct flash distance and focus is kept the same distance, for TTL BL D-lens).

Click to expand...

Hi Wayne, there is evidence out there they suggests that TTL-BL mode has moved away from the central area after D100. This is one of such tests. which I find to be quite accurate in my own uses.

daredevil123 said:

Hi Wayne, there is evidence out there they suggests that TTL-BL mode has moved away from the central area after D100. This is one of such tests. which I find to be quite accurate in my own uses.

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LOL. Yes, we certainly can read many things on the internet. You can count this as just another one, or the hope is that you can try it yourself to see how it actually does work. Desmond does try hard, but he makes big leaps to conclusions, and FWIW, I question many of them.

If you care where flash meters, then you definitely ought to try it yourself. Let me show you. Here is a black card, a gray card, and white card, conveniently taped to my TV screen at about six feet. This is a D800, it is newer than Desmond's proverbial D100. My D300 also does the same as this. And a hot shoe SB-800 flash. ISO 400, f/5, 1/200 second. A real simple situation, point and shoot, except the focus sensor was moved on each. Done in five minutes, this morning, just for you. This is VERY repeatable. Unadjusted here, TTL BL is often a bit underexposed (just needs simple compensation).

First row is direct TTL BL flash in Matrix metering mode. Focus sensor left to right is on the three cards.

Second row is bounce, TTL BL in Matrix metering mode. Focus sensor left to right is on the three cards. (ten foot ceiling, seven feet up)

The focus sensor was moved left to right, which really could not matter less here which way it moved, since there is no difference.








There are two metering systems in there. Ambient is in fact metered at the sensor, but this is insignificant ambient, shutter speed 1/200 second to keep it out.

We know that if it actually metered flash on the black card, black would necessarily be gray, and we would need about -2EV compensation to make it show as black (but we don't here).

And we know that if it actually metered on the white card, white would necessarily be gray, and we would need about +2EV compensation to make it show as white (but we don't here).

Point is, these are all alike, all are actually metered on a central area, regardless of focus point. You should try this yourself, to know.

I left white balance at Flash WB, unadjusted, just to make another point. We also know that flash color varies with flash power, and this is two extremes. Near direct flash at low power will be blue (if speedlights), and full flash power can be slightly red. There is about 1000K difference in these two sets, unadjusted (again, this is two extremes).

WayneF said:

LOL. Yes, we certainly can read many things on the internet. You can count this as just another one, or the hope is that you can try it yourself to see how it actually does work. Desmond does try hard, but he makes big leaps to conclusions, and FWIW, I question many of them.

If you care where flash meters, then you definitely ought to try it yourself. Let me show you. Here is a black card, a gray card, and white card, conveniently taped to my TV screen at about six feet. This is a D800, it is newer than Desmond's proverbial D100. My D300 also does the same as this. And a hot shoe SB-800 flash. ISO 400, f/5, 1/200 second. A real simple situation, point and shoot, except the focus sensor was moved on each. Done in five minutes, this morning, just for you. This is VERY repeatable. Unadjusted here, TTL BL is often a bit underexposed (just needs simple compensation).

First row is direct TTL BL flash in Matrix metering mode. Focus sensor left to right is on the three cards.

Second row is bounce, TTL BL in Matrix metering mode. Focus sensor left to right is on the three cards. (ten foot ceiling, seven feet up)

The focus sensor was moved left to right, which really could not matter less here which way it moved, since there is no difference.


There are two metering systems in there. Ambient is in fact metered at the sensor, but this is insignificant ambient, shutter speed 1/200 second to keep it out.

We know that if it actually metered flash on the black card, black would necessarily be gray, and we would need about -2EV compensation to make it show as black (but we don't here).

And we know that if it actually metered on the white card, white would necessarily be gray, and we would need about +2EV compensation to make it show as white (but we don't here).

Point is, these are all alike, all are actually metered on a central area, regardless of focus point. You should try this yourself, to know.

I left white balance at Flash WB, unadjusted, just to make another point. We also know that flash color varies with flash power, and this is two extremes. Near direct flash at low power will be blue (if speedlights), and full flash power can be slightly red. There is about 1000K difference in these two sets, unadjusted (again, this is two extremes).

Click to expand...

Wayne, I think you misunderstood. What Desmond is saying is that the metering is based on the brightest AF point. Not the selected AF point. so moving AF points does nothing.

I did this test before many times because I wanted to be sure. My conclusion is that on TTL-BL, the introduction of a bright object in the frame over any AF point matters. It is not just a simple middle of the frame metering. I have also shot with perfect flash exposure where the people in the frame is not in the center with a dark background. By your reasoning, those kind of pictures should result in the subject being over exposed, but they did not.

Perhaps you can explain why the flash power for the following two pictures differ?

Pictures shot moments from each other a couple of minutes ago. D4 + SB-600 (on TTL-BL), FV0, EV0, 1/160s, F5.6, ISO200, Matrix. No settings changed between the shots. camera on tripod. AF point on center point. Pictures are out of camera JPG, unadjusted, but resized to 1024 on the long end.

daredevil123 said:

Wayne, I think you misunderstood. What Desmond is saying is that the metering is based on the brightest AF point. Not the selected AF point. so moving AF points does nothing.

Click to expand...

OK, I have to admit to not paying much attention.

I did this test before many times because I wanted to be sure. My conclusion is that on TTL-BL, the introduction of a bright object in the frame over any AF point matters. It is not just a simple middle of the frame metering. I have also shot with perfect flash exposure where the people in the frame is not in the center with a dark background. By your reasoning, those kind of pictures should result in the subject being over exposed, but they did not.

Perhaps you can explain why the flash power for the following two pictures differ?

Pictures shot moments from each other a couple of minutes ago. D4 + SB-600 (on TTL-BL), FV0, EV0, 1/160s, F5.6, ISO200, Matrix. No settings changed between the shots. camera on tripod. AF point on center point. Pictures are out of camera JPG, unadjusted, but resized to 1024 on the long end.

Click to expand...

Why they differ is because there is some metering area. We may not always be clear on what that area is, or its size extent or definition or rules (which is your debate), but we do know all metered areas try to convert to a middle gray result. Simply what meters do. Only possible thing they can do. Because, they can only see a spot of light, and can measure it, but the dumb silicon chip cannot recognize if is your Aunt Jane or a kumquat bush. It has absolutely no clue what it is, or how it ought to be. The meter knows nothing that humans know in a glance, we know what it is and how it should be. So, what the meter can do is that dark colors (like black) are made to be gray, or lighter (overexposed). Light things (like white) are made to be gray, darker, underexposed. So if you introduce white into the metered area, it is going to get darker. There is no other choice.

I agree that no one knows what Matrix metering does. It is just a dumb computer with no clue what our image is or how it should be, but nevertheless it is a computer program, designed to make assumptions about our pixels, and trying to do something to "help" us, or so marketing says. Nikon does not tell us what Matrix does, we simply do not know, not even a first clue. It would be good if they would tell, but they probably cannot. Frankly, I can almost understand and visualize what Center metering does, and will do, and which I can predict, and that concept is easy and understood, so I greatly prefer it, rather than guessing about it.

TTL BL is the same in smaller degree, a small subset with much less scope, but since any two correct exposures of any two lights (like sunlight and TTL flash, or like two TTL flashes, etc)... when and if any two lights combine, and if both are correct exposure, then that is two exposures worth, and one stop overexposure by definition. That is what TTL will do in sunlight for example, so photographers know they have to compensate it. The TTL goal is to meter the flash and to give a correct flash exposure, regardless, no matter what (often correct indoors). Whereas TTL BL has the single goal of auto compensation, of backing off on the flash (called fill flash, balanced with ambient) - to avoid this combining situation. Often to a fault when there is no significant other light, but it is not risking overexposure.