I won't say everyone do this, but usualy I see P mode users who use
ETTL meter at the same time. So every time I hear P mode I think of
ETTL at the same time.
The two aren't linked. The metering and the P mode are separate entities.
If you use the camera for metering, then all the P mode is doing is setting a pair of values that are correct for that metered EV. The camera just sets the aperture and shutter variables - and even then if you aren't happy with the pair it has set then you can shift them. Try it.
What is being metered by the camera is a an EV from the scene. Regardless of any averaging, the camera's metering provides you with an EV value at it's output. Program just set's the shutter and aperture to give that EV. It is up to the photographer to interpret the scene from experience. If necessary exposure compensation can be applied. Whatever creative mode you are in.
The human dress is more important than the dress usually. You need
to make a correction in P mode or swithch to M and spot meter the
face.
So you spot meter the face, (which was overexposed before by your argument, with the dress being grey. So what do you do? You apply a little less exposure to get the face right. That's fine - you can do that in P mode too. The flaw in your logic is that reducing exposure to get her face right, makes the dress even more grey according to the scenario you outlined above
)
This is why I work in M usually. Making corrections simply takes to
much time than making just one shot which is correctly exposed.
You have to make the same correction whether in M mode or P mode, or in Av or in Ts - it makes no difference. What you are talking about is a lighting/exposure situation in which the camera's metering is being fooled. So you adjust exposure to compensate. Which can be done in P mode.
You seem to have some kind of misconception about what P mode is. In M mode, if you are using the camera's meter, you will go through the following steps - set aperture to give you the dof you want. Set shutter speed to give a matched EV. Find out that it's underexposing the dress etc. Adjust shutter speed (say, up or down accordingly) and take the shot.
In P mode, the camera would set both Ap and Shutter automatically. Evaluate the settings in the VF - like them? ok, no? Shift them. Take the shot. Don't like the exposure? Compensate using the Exp Comp dial. Results are identical
When we compared the photos, my photos were
correctly exposed, but the white dress his photos was mostly
overexposed.
That's a metering issue, not a mode issue.
You're completely wrong here. It depands of what are you shuting.
In case you take photos of flowers, cats,... with a good lighting
condition and you're satisfied with the results then you're correct.
There are circumstances where P mode is not suitable (the same with any of the other modes), but you have completely confused metering, with a program mode. They are separate entitites.
You've even confused metering as an issue - I'd like to hear what steps you would take in M mode to correct the situation where you have an overexposed brides face, and a white dress that is coming out too grey.
But also with flowers a professional photographer wouldn't be
satisfied using P mode. Maybe the exposure would be correct, but
it's not just the exposure. It's also DOF. In this case you should
select Apperuture, which means you need AV mode instead of P mode.
You really don't understand the P mode at all. P mode might suggest f4 at 1/800 say. You know that from experience, you are going to need f8 for that shot. Spin the control dial by your shutter to give you f8 at 1/200. Quick, simple, efficient.
Some more extreme conditions.
- Go to a valleyball competition and use P mode. What will you get?
Just blured photos. Why? Because you need very short times and the
camera doesn't know you take photos of the valleyball competition.
Of course, the camera can never know what you are taking. It will still meter to give you the best exposure it thinks fit - if it sets the shutter speed slower than you like, shift it. However, if you are having to consistently shift, then you would be better in Ts mode. It's a case of correct mode for the job. In the same way that you might not use Av in that circumstance, then you might not use P.
- Go to a dark place with flash. P mode will select 1/60 which is
to short. You only get black & white photos. I sometimes use even 2
seconds (but mostly drom 1/15 to 0.5") which gives me much better
colors.
Flash on the Canon system is a special case, so use the more appropriate mode. In this case, Av will do what you want.
Using M mode nearly all of the time gives you a practice wich helps
you to solve situations where P mode is impossible to use.
M mode is the slowest of all the modes to use as it involves setting two variables to match the metered Ev. Av or Ts need one variable set to match the metered Ev, automation taking care of the second. P sets all variables for a metered EV, and allows shifting up or down in Aperture/shutter speed whilst maintaining the correct exposure. If the METERING has got the exposure wrong, Exp Comp can correct it.
there are situations where you can't use P
mode and you need to be prepared for such situations.
Of course, but if one is using the camera's metering (with the exception of flash, as that is a special case), then identical results can be obtained using either Av, Ts or P modes, quicker than in M mode, as fewer variables need to be set. You have no more control in M than you have in Av, Ts, or P.
Simon
