"William Graham" <weg9@comcast.net> wrote in message news:P8hub.175935$9E1.916155@attbi_s52...

> "David Ruether" <rpn1@no-junk.cornell.edu> wrote in message

> news:bpbgar$htu$1@news01.cit.cornell.edu...

> > "Matt Clara" <no.emailz@this.guys.expense> wrote in

> > message news:UD9ub.195805$Te.1415660@news.easynews.com...

[...]

> > > Sometimes P is the best tool for the job, in which case these fine tools

> > > _should_ be used in P mode, at least when the situation warrants it.

> > This is true - but a rare condition, IMHO. As with wedding photography,

> > where using P mode most of the time will cause severe underexposure

> > of the low ambient-light levels found at weddings much of the time - and

> > it may also force the lens wide open, which is often not always ideal for

> > best image quality. 1/30th and even 1/15th or slower shutter speeds are

> > often useful, especially when using wide-angle lenses which can be

> hand-held

> > at slow speeds and which often need to be at f5.6 for good performance.

> > For the original poster, use of P in a studio situation doesn't work if

> there

> > are reasons why 1/250th shutter speed is desireable (noticeable light

> sources

> > or reflections from these that should not predominate in the exposure is

> > one reason) and since program mode may force the aperture too wide

> > for the set-up. Knowing photographic techniques and having good tools

> > often help in producing better/more-varied images than mere snapshooting

> > with fully automatic controls engaged will - which the newer cameras

> > (even the good ones) now permit...;-)

> > --

> > David Ruether

> As long as you can achieve full control, I don't think it really matters

> which mode you are using....I can fudge the program in P mode with the

> control wheels, and that seems to work OK. Where I seem to have difficulty

> is figuring out how to use fill flash.....I can use the flash in P mode, and

> the pictures seem to come out OK, but it bothers me that I don't really know

> what the camera is doing......Exactly what percentage of the light does it

> get from the flash? How can I force the camera to use (for example) 66%

> ambient light, and 33% light from the flash? Should I go to manual mode and

> intentionally underexpose by 33%? - Will it then make up that 1/3 stop with

> the flash?

Ah, but you are "proving" my point...;-)

In "P" mode, the shutter is limited to 1/60th-1/250th regardless of

what you adjust when using flash, which limits your ability to properly

match the lens FL to the best shutter speed and aperture selection

for optimum ambient-light exposures when shooting in the abysmally

low light levels often found in churches and in reception halls. Using

just the auto fill ratios also results in too much fill-flash - and the amount

of fill-ratio that the camera-flash combination is using is unknown

and undetermined by the photographer. With Nikon gear (and some

others), you can turn off the auto fill ratio (which is -0 to -2/3rd stop,

depending on amount of ambient light underexposure). Switching to

A, S, or M modes permits a wider range of shutter speeds to be selected

with flash (F100, F5) and this gives you better control over the aperture

selected for correct low-light exposure. You can then disable the auto

fill ratio and select your own ratio in 1/3rd stop increments. For color

negatives, I find -1 *stop* (not one increment) flash TTL underexposure

works well much of the time - though in very low light, I may decrease

this to "0" for 1:1, and increase the film ASA rating 2/3rds of a stop

(since both the ambient light and flash light are contributing full

exposure). With all, I always set the ASA 1/3rd-2/3rd stop lower

on the camera than the film rating for a bit more "pad" for accidental

underexposure with white walls or if the lighting color balance is

far from daylight (which it usually is). BTW, "fill-flash" is just

that: it is light added to full normal ambient-light exposure to raise

the lower tones slightly. Used well, the flash rarely distinctly shows

in the photo - except as more "open-looking" shadow areas...

--

David Ruether

d_ruether@hotmail.com

http://www.David-Ruether-Photography.com