Fill flash on the D750 - Is the option really there?

voxmagna

Senior Member
I have been all around the manual and cannot get my D750 to set options on Page 185 Flash Control Mode i-TTL balanced fill-flash for digital SLR using built in popup flash.

I'm using matrix metering mode, 'A' priority and do not see the Flash Mode option on page 183: 'Fill Flash: The flash fires with every shot.
I took some shots behind a nice enclosed dark brick archway. The foreground was obviously very dark, whilst through the arch was good daylight metered and exposed correctly.

Using a lowish ISO of 150 -200 I was able to pull up the brick arch 'shadows' in post, but what I needed was fill flash technique: Expose for distance, adjust or meter flash power for foreground. I've tried a number of test options since and I appear to be fighting the camera metering. As I read my manual (several times), the functionality of foreground flash metering should be built in and fill shots even with the flip up flash should be easy.

Can anybody else confirm with latest Nikon firmware they are seeing a Fill flash control option? If not how are you all achieving fill flash?

Thanks
 

grandpaw

Senior Member
I have never tried using the on camera flash for fill but I would think it would work the same as using an external flash. The only way you can control them separately that I know of is too shoot in manual mode. F stop will control amount of flash used and the shutter speed will control the ambient light.
 

voxmagna

Senior Member
Yes I tried some more experiments. You can still use aperture priority matrix metering for the distant scene, but go into Manual Flash and set flash power low for the foreground fill. But what a pain because you have to go through the menu options to do it, when it would have been nice to press one of the buttons, select flash power and use a function wheel - Unless I've missed something?

I just can't understand the Nikon menu option which specifically mentions fill flash. I don't know how it would work and can only guess that the far scene is exposed through the metering in the normal way on half shutter press. Then on shoot the foreground gets a flash bounce back from the first flash, then sets the flash power for the second as the fill but doesn't change the matrix metering. But I cannot get the feature they describe in the manual. I just hope Nikon haven't got rid of it in a firmware upgrade (downgrade!).

Most would probably agree that the flip up flash is not the best, but just to add a little foreground lighting without carrying a shoe flash is very useful. I tried out the rather tedious manual method shooting some outdoor portraits and was pleased with the results using about 1/20th - 1/40th flash power.

Can anybody find this fill flash feature in their flash menu settings?
 

WayneF

Senior Member
I have been all around the manual and cannot get my D750 to set options on Page 185 Flash Control Mode i-TTL balanced fill-flash for digital SLR using built in popup flash.

It is confusing, since these options are not directly set in the camera. My notion is that they should be. :)

Balanced fill flash is called TTL BL mode, which is also not directly set in the camera. Some bigger Nikon flashes have a TTL vs TTL BL menu on them. Only current model is the SB-910 now. And older SB-800, SB-600, but all the others are TTL BL by default. No menu for TTL vs TTL BL.

Nikon is a TTL BL system, and TTL BL is simply the default for the camera internal flash too, so you do already have it (fill flash).

"Fill" can be disabled (to be the other "standard iTTL) by selecting Spot Metering mode (see last line there, page 185).

However Spot has lots of other issues for ambient. Ambient users need to understand Spot metering. Without a clue about Spot, all you will get is radically variable exposures in ambient situations.

But all Spot means to the flash (speaking indoors, where ambient does not matter to flash) is that it comes ahead strong, using the actual flash metered intensity, instead of backing off to be reduced for fill flash.

I'm using matrix metering mode, 'A' priority and do not see the Flash Mode option on page 183: 'Fill Flash: The flash fires with every shot.

The manual is confusing about this. The top icon on page 183, called Fill flash, does NOT SAY Fill flash in the LCD. It shows just the same blank icon (no words or icons in it), same as the manual shows. It actually just means regular Front Curtain Sync, and specifically means NOT one of the other choices there. The camera internal flash is TTL BL, and so is already Fill Flash, by default. You already have it (unless you select Spot metering).

I took some shots behind a nice enclosed dark brick archway. The foreground was obviously very dark, whilst through the arch was good daylight metered and exposed correctly.

Using a lowish ISO of 150 -200 I was able to pull up the brick arch 'shadows' in post, but what I needed was fill flash technique: Expose for distance, adjust or meter flash power for foreground. I've tried a number of test options since and I appear to be fighting the camera metering. As I read my manual (several times), the functionality of foreground flash metering should be built in and fill shots even with the flip up flash should be easy.

Fill flash normally has little meaning or effect indoors, unless very high ISO to pull the ambient up. Ambient is usually way down indoors (reason we are using flash), and ignored, and "fill" has little meaning then.

But in your case, the ambient was strong daylight through the arch. The fill effect in bright daylight will be to reduce the flash level by about two stops, to be lower fill level. Otherwise, the added TTL flash will overexpose the regular ambient that is already metered correctly there. But TTL BL will try to reduce the flash level if there is meterable ambient, and that is one meaning of fill flash. Filling shadows is the regular meaning.

However, daylight is very bright, and I suspect your foreground was very dark, and any fill effect would just make it darker. Fill flash means reduced relative to the ambient, which was NOT your goal there. Your test had an extreme dramatic range, not a regular "fill flash" situation.

Solutions to your question:

You could increase the flash with Flash Compensation, however it only allows +1 EV, which is not going to make much difference (in your dark wall case).

In this extreme case, you could aim the camera and the center focus point left or right, directly at the dark wall. Then after setting up camera FV Lock, and reading how to use it, you could push the FV Lock button aimed at the dark wall. That will do a little preflash and will meter the flash for that situation (assuming flash power capability is sufficient for the distance range).
Then recenter camera and take picture, and it will use the previous FV Lock flash value (much stronger flash then, metered for the dark area it was previously aimed at). Do read about FV Lock.

Can anybody else confirm with latest Nikon firmware they are seeing a Fill flash control option? If not how are you all achieving fill flash?

Thanks

To learn about fill flash, start with simpler, more usual and regular flash tests. A photo of a persons face outdoors. Or it could be a flower pot, etc, standing with back or side to the sun, so there are harsh shadows on the face or front. Then (if distance is close enough for little internal flash), then regular fill flash will make a dramatic improvement.

The tiny internal flash might have range for reduced fill flash level up to about 6 or 7 feet in bright daylight (at aperture settings for sun). Bigger speedlights can do a lot more.

See Flash pictures are Double Exposures- Outdoors for an example. Point & shoot fill flash with default TTL BL.
 
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voxmagna

Senior Member
Wow, I could not have wanted a more comprehensive quality reply! Straight on the money with my problems too.

Nikon is a TTL BL system, and TTL BL is simply the default for the camera internal flash too, so you do already have it (fill flash).
That explains why I see TTL BL in the EXIF data with the flash raised.
I understood about spot metering and set matrix metering expecting to see the option available, which you explained is a misunderstanding on my part.
But TTL BL will try to reduce the flash level if there is meterable ambient, and that is one meaning of fill flash. Filling shadows is the regular meaning. But in your case, the ambient was strong daylight through the arch. The fill effect in bright daylight will be to reduce the flash level by about two stops, to be lower fill level. Otherwise, the added TTL flash will overexpose the regular ambient that is already metered correctly there.
The camera internal flash is TTL BL, and so is already Fill Flash, by default. You already have it (unless you select Spot metering).
I have selected the option to NOT automatically popup the flash when the camera thinks it needs to, but I would still expect the front curtain default when I raise the flash manually.

I tried an equally challenging shot from indoors with an an open patio door in the center of the scene. Leaving the matrix metering and flash to work it out I got poor results. Then I exposed the same shot with no popup flash metering for outdoors, previewed the result and as expected outdoors was correct (metering worked as expected), indoors was under exposed. I switched to manual flash and re shot the same scene several times with increasing increments of flash power. At around 1/20 flash power, indoors was nicely exposed whilst outdoors remained exposed correctly. Perhaps I was expecting too much for the camera to work out this type of scene? I will repeat what I did again, go back and look at the exposure data. If it stays the same flash up or down and only the flash power is changing, then I will be happy camera flash is not modifying metering. If the exposure is changing then I will remain puzzled because I still haven't understood how the camera knows how to throw lots of flash light for a dark indoor shot, yet only a small amount for a short range subject dimly lit with daylight behind.
You could increase the flash with Flash Compensation, however it only allows +1 EV, which is not going to make much difference (in your dark wall case).
Correct, I tried that and as you say, +1 is insufficient.
To learn about fill flash, start with simpler, more usual and regular flash tests. A photo of a persons face outdoors. Or it could be a flower pot, etc, standing with back or side to the sun, so there are harsh shadows on the face or front. Then (if distance is close enough for little internal flash), then regular fill flash will make a dramatic improvement.

I've got the Meke MK910 I can try.

Thanks for the link.

Perhaps I'm thinking to simply, but when I am standing 2 metres behind a dark brick arch looking through at a good daylight scene, I know the popup flash can light the brickwork. Perhaps in practice the camera cannot 'automatically' expose this correctly because it cannot differentiate between the high brightness daylight it meters and any pre-flash light bounced back. Which is why manually setting the flash power although requiring more test shots, can be made to work. I shall spend more time reviewing my test shot EXIF data because that will tell me if the flash is being fired, at what power level and whether exposure compared to flash 'off' is being modified.




 

WayneF

Senior Member
I have selected the option to NOT automatically popup the flash when the camera thinks it needs to, but I would still expect the front curtain default when I raise the flash manually.

Front Curtain is not a default exactly. It is standard, but is a setting there, for any flash, not related to just the popup.

True all other settings there except Rear Curtain are Front, but others also do other things. If you want just regular Front Curtain, here is where you specify it. If you specify it, then it is like default, what will be used.

I tried an equally challenging shot from indoors with an an open patio door in the center of the scene. Leaving the matrix metering and flash to work it out I got poor results. Then I exposed the same shot with no popup flash metering for outdoors, previewed the result and as expected outdoors was correct (metering worked as expected), indoors was under exposed. I switched to manual flash and re shot the same scene several times with increasing increments of flash power. At around 1/20 flash power, indoors was nicely exposed whilst outdoors remained exposed correctly. Perhaps I was expecting too much for the camera to work out this type of scene? I will repeat what I did again, go back and look at the exposure data. If it stays the same flash up or down and only the flash power is changing, then I will be happy camera flash is not modifying metering. If the exposure is changing then I will remain puzzled because I still haven't understood how the camera knows how to throw lots of flash light for a dark indoor shot, yet only a small amount for a short range subject dimly lit with daylight behind.

Matrix metering is for the ambient contribution, and it does see stuff at the frame edges. Regarding ambient. Your arch situation might be better with Center Weighted metering (for ambient).

But TTL flash meters in the center, regardless. Seems contradictory, but maybe it did not think your daylight arch needed much flash? Certainly the flash goal was not the center part. It is a difficult situation, more attention than point&shoot will be necessary.

The FV Lock thing should work well, explained before. Or manual flash should work. But straight point & shoot flash probably won't satisfy in that difficult situation. It is a case when the photographer gets involved. :)

Perhaps I'm thinking to simply, but when I am standing 2 metres behind a dark brick arch looking through at a good daylight scene, I know the popup flash can light the brickwork. Perhaps in practice the camera cannot 'automatically' expose this correctly because it cannot differentiate between the high brightness daylight it meters and any pre-flash light bounced back. Which is why manually setting the flash power although requiring more test shots, can be made to work. I shall spend more time reviewing my test shot EXIF data because that will tell me if the flash is being fired, at what power level and whether exposure compared to flash 'off' is being modified.

It is a tough unusual situation for the automation.

But FV Lock can meter the dark wall for the flash, and then the arch for the ambient. I think that is your goal. It may be a bit strong then (FV Lock is not a fill situation), but then a bit of flash compensation might be helpful. You have +1 or -3 EV available.

Flash compensation only affects automatic TTL flash mode, but its control is a little like manual flash... we can adjust it like we want it.

The advantage over manual flash is TTL selects a much closer starting point, and it is metered, so when compensated, it can still automatically adjust for many routine changes, into similar but different situations.
 
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voxmagna

Senior Member
Thanks, I fully understand what you are saying. Sorry for being a new poster and asking a question more complex than I expected. Whilst I was trying to work this out for myself I remembered seeing small handy cams firing their (small) flashes in what I thought was reasonable daylight. But now I think about it, perhaps they were not defaulting to flash all the time but struggling to get focus as many do. Getting back finding shots out of focus with poor low light performance and high ISO noise is why I wanted to move to full frame DSLR, despite the bulk and weight load.

As I said earlier, I can 'bend' shadows in post to get a dark brick arch foreground to look good whilst preserving the distant highlights. With ISO around 150 it is surprising how the shot can be compensated without too much additional noise. The other thing I am enjoying is using the f1.4 50mm prime lens with artificial indoor light. Zero problems with focus, acceptable noise without pushing up the ISO and no red eye!

Thanks again - Vox
 

voxmagna

Senior Member
Success!!

I Programmed the Fn button to FV Lock and shot some test photos inside rooms looking out through open windows in center frame. Perfect once I realized I had the 24-120 zoom at wide angle and the popup can't fill that wide! Fine with a 50mm prime lens. I could tell the flash power was way down on the compensation range you can get for flash output and close to the manual 1/20 power level I had tried before.

Here's the Nikon answer for setting up and using FV lock:
https://nikoneurope-en.custhelp.com/app/answers/detail/a_id/23820/~/what-is-fv-lock?
 

WayneF

Senior Member
Re: Success!!

I remembered seeing small handy cams firing their (small) flashes in what I thought was reasonable daylight. But now I think about it, perhaps they were not defaulting to flash all the time but struggling to get focus as many do.
...
Zero problems with focus, acceptable noise without pushing up the ISO and no red eye!

Frankly, most of them just don't know how to turn the flash off. :)

Red eye is caused by only a tiny distance between flash and lens, so that the flash reflects directly back from inside the eye. An external hot shoe flash is taller, which greater angle of separation helps tremendously to mostly prevent red eye, most of the time. Bounce flash is best of all, for that and other reasons.

I Programmed the Fn button to FV Lock and shot some test photos inside rooms looking out through open windows in center frame. Perfect once I realized I had the 24-120 zoom at wide angle and the popup can't fill that wide!

That is very surprising to hear about 24mm. I rarely use the internal flash, other than as a commander. But I don't have any issue with the internal flash at 24mm though, it is wide enough here. Just tested it again now, with a Nikon 24-120 at f/4 and 24mm, and I see no flash width issue at all. My issue is that it has only minimum power and range, and no bounce capability. :)

Sometimes wide angle lenses do vignette noticeably at wide aperture. You'd see that without the flash too. We get used to it, may not always notice it.
 
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