TTL and manual camera exposure settings

[johann_o]

I am using a TTL camera and flash and wonder if the TTL system will

work propberly if I set the camera exposure manually. I mean: will

the TTL system ensure correct exposure even if the camera is not

in "P" mode, but in "M" mode? If there is almost enough light to

shoot without flash, will the TTL system take into account the fact

that I might be letting much more available light into the camera

than in "P" mode due to my specific manual settings? Unfortunately,

my camera manual doesn't tell. I have a Nikon F80 along with a Metz

44 AF-3N flash.

 

Of course I could easily test this, but then I would never know if

wrong exposure was later corrected by the photo lab. And unless I

have a definite answer, I would not want to use manual settings on

important unrepeatable occasions.

 

I want to manually set the camera to 1/30-1/20 and f8 to prevent

black backgrounds and obtain sufficient depth of field

for "photojournalistic" pictures that look ok even if people are at

different distances from the camera.

 

All advice will be greatly appreciated.

[john lehman, college alask]

At least on older Nikon cameras (like the FE2), TTL works fine in manual mode. I doubt if Nikon would have eliminated this feature on later cameras.

[todd peach seattle, washi]

TTL will work fine, independently if you like, if the camera is in M mode. At its most basic, it is examining the light falling on the film from the flash, and it decides when 'enough' has fallen to give a correct flash exposure and then it quenches the flash.

 

'Dragging the shutter' (as you say, 1/15 or 1/30) is a time-honored method of getting the indoor background to render more as our eyes see it. If you're more comfortable with it, you can use one of the cameras auto modes, even program, and slow or rear sync.

 

It's still not a magic bullet for making people look OK at different distances from the camera. People further from the camera will be more 'orange' or whatever the color balance of the available light is.

 

I find it useful to think in terms of guide number or 'f-stop distances' when I'm trying to gauge how a flash will light a scene. If your main subject is 8 feet away and the flash system meters it correctly, then objects at 5.6 feet will be overexposed one stop, objects at 11 feet will be underexposed one stop, 16 feet down two stops, 22 feet down three stops, etc. This is why the classic 'shoot from the head of the banquet table with on-camera flash' is almost always a dismal failure.

 

By all means experiment and learn a style that works well for you. For me, the PJ look is mostly about fast film, fast glass, minimal flash. Try some Fuji Press 800 with a lens that is f/2 or faster. Add a 'touch' of flash when you have to. Part of the 'look' is the way folks interact (or not) with you. Not using a flash is part of the 'fly on the wall' aspect. Folks tend to ignore you.

 

Don't rely on a new technique for any "important unrepeatable occasion". Practice it first. Another way to practice is to vary your technique during those occasions (I assume you're not the paid photographer, just doing it for yourself/friends/family). Shoot the bulk of the shots using methods you're very familiar with. This is your 'insurance'. When you have those done, then play with bounce flash, dragging the shutter, off-camera flash cord, etc. Take a few notes if you can, so you can view your results with a more educated eye on what worked and why.

[scott_blair1]

Lately I see questions like this a lot. I wonder why. There is too much obsession with the minutia of Nikon TTL flash. To the point, the type of TTL is determined by the metering pattern---spot, CW, or Matrix---not whether you or the camera selects the shutterspeed and/or aperture. Most of the info that circulates around the Net is second hand, untested, and based on the gross misconception that the newer the technology or fancier the name, the better the result. Yes, you should test it yourself. If the lab might override the test, than it doesn't matter anyway. If you had a manual, you would know about slow synch, which allows the shutterspeed to float when using aperture priority.

[andrewdawsongallery]

>>the type of TTL is determined by the metering pattern---spot, CW, or Matrix<<

 

Actually, the TTL meter is separate from the ambient light meter, which you can set to one of the above settings. The TTL meter is center-weighted, and if your flash is TTL ready, will base the overall exposure on that *combined* with whatever ambient exposure you've chosen. This way, if you were in spot mode, the TTL flash system wouldn't try to get the correct exposure on only that spot, but would still consider the entire frame. True on the F4 anyway, I'd be surprised if it was much different on the N80/F80.

 

This might be too much obsession with TTL, but IMHO, flash is one of the more poorly understood aspects of photography. If more information can help people to make better creative decisions, what's wrong with that? If David is concerned about the lab "fixing" any errors, I'd suggest shooting some tranparency film for the tests. Slide film won't lie about any of your results...

[jim mucklin]

David, I can't speak for your flash, but rear sync, in P mode will get you what your looking for, let me know if you got my e-mail.

[lachaine]

If you put the F80 in manual exposure mode, you get standard TTL flash. If it's in any automatic mode, you get 3D multi-sensor balanced flash. The difference is sort of analogous to the 3D matrix exposure meter compared to the centreweighted meter. The 3D multi-sensor balanced flash is better for fill flash, while standard TTL may be better if the flash is the main source of light - but I think you would have to experiment for yourself. 3D multi-sensor balanced flash works pretty much in any situation, as far as I can tell.

[ellis_vener_photography]

With F5, N90/90s, D100, D1X, D1H and Nikon Speedlights the short and correct

answer is yes.

[scott_blair1]

Andy, Pierre, please tell us your source. Oh, and if you have the N80.

[andrewdawsongallery]

Scott--I can quote the Moose Peterson guide to the F4, p. 131: "It's important to understand that the meter doing the work in the TTL system is center-weighted. Any reference to Matrix-balanced fill-flash or Center-weighted balanced fill-flash is referring strictly to ambient light metering." My own experience affirms this too; when I've left the meter in Spot mode and used 100% flash, the exposures are still correct.

 

I don't own the N80, but I would be surprised if its system was hugely different. The logic of it makes sense. This is the kind of thing that is transparent to the user most of the time, especially if you use Program or AP modes. Cheers...

[bob_heff]

For the F80/N80, F70/N70, & F60/N60, standard TTL flash-metering will operate correctly when the camera is in Manual Exposure mode. For advanced TTL flash metering, use either A-, S-, or P- modes. If the camera is on a tripod or other solid support, one can use slow-sync.

 

In A-mode (without slow sync), the F80/N80 and the F70/N70 will swing between 1/125 and 1/60 speeds, depending upon the ambirnt light.

 

Regardless of the ambient-light meter being set for matrix, center-weighted, or spot; the TTL-flashmeter is operating in a five-part matrix. To visualize this matrix, look into your viewfinder and mentally draw a vertical line thru the center of the finder and a horizonal line also thru the center of the finder, quartering the finder. Now erase the crossing lines within the 12mm-ring. This will approximate the five-areas of the matrix.

 

The TTL-flashmeter will handle the flash exposure without regard to what the ambient-lightmeter is doing. That is why the F80/N80 and F70/N70 have a flash-compensation control in addition to the ambient-light compensation control.

 

So get a roll of "slide" film and

test shoot before your next photo-op.

[scott_blair1]

Bob, what's your source for this detailed info?

[bob_heff]

Scott:

Magic Lantern Guide for N70/F70 by Gunter Richter,

as translated by Hayley Ohlig, pages 100 theu 114.

Bob