The manual is not very clear about exactly what is controlled in the P mode. It just says that aperture and shutter speed is set by the camera, but it doesn't tell much about how to use this setting and what control I have over the camera. Is there a tutorial for the P mode?? I almost always use the Manual mode, but was wondering if there is something in the P mode that could be of benefit.
How does the camera function in P mode?
- Thread starter Jim_Y
- Start date
Horoscope Fish
Senior Member
"P"rofessional mode is one step away from full-automatic, in my opinion. What it does, in short, is select a combination of aperture and shutter speed. You turn the Command Wheel and you get pre-configured combinations that ensure correct exposure. And by correct I mean according to the meter, not according to what you want.
For further reading: Understanding Program Mode
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Its Just Me
Senior Member
You're putting it in "P" mode. Thats whats wrong!
Auto is rather different than P mode.
Auto also forces Auto ISO and Auto WB to be on. And flash pops up automatically. It is full Auto, like a phone camera.
But P mode does not, it is only auto exposure. But you can set these others on if you want them. If you do, you might as well use Auto.
And P mode is "scrollable", for other combinations of same exposure, but with faster/slower shutter speed.
Auto ISO might not be on, but even if it is, scrolling P mode is the SAME exposure, which is why Auto ISO is not changing. Auto ISO changes according to the light it sees in the scene (and also reacts to DIFFERENT camera exposures).
P mode scrolling is all about Equivalent Exposure.
The only real difference in P mode and A mode is that in A mode, we choose the aperture first.
P mode chooses it too, but can be scrolled to other values.
There are some small subtle differences in P mode. For example, with flash, P mode will limit the maximum aperture that can be used. This is not really about flash, it is said to be about the range of the EV meter, but the maximum aperture allowed is further stopped down 1/2 stop per each stop of higher ISO. So if planning to use your new f/1.8 lens with flash at f/1.8, then you need camera mode A or M.
Auto also forces Auto ISO and Auto WB to be on. And flash pops up automatically. It is full Auto, like a phone camera.
But P mode does not, it is only auto exposure. But you can set these others on if you want them. If you do, you might as well use Auto.
And P mode is "scrollable", for other combinations of same exposure, but with faster/slower shutter speed.
Auto ISO might not be on, but even if it is, scrolling P mode is the SAME exposure, which is why Auto ISO is not changing. Auto ISO changes according to the light it sees in the scene (and also reacts to DIFFERENT camera exposures).
P mode scrolling is all about Equivalent Exposure.
The only real difference in P mode and A mode is that in A mode, we choose the aperture first.
P mode chooses it too, but can be scrolled to other values.
There are some small subtle differences in P mode. For example, with flash, P mode will limit the maximum aperture that can be used. This is not really about flash, it is said to be about the range of the EV meter, but the maximum aperture allowed is further stopped down 1/2 stop per each stop of higher ISO. So if planning to use your new f/1.8 lens with flash at f/1.8, then you need camera mode A or M.
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So, essentially there is no such thing as auto ISO in P mode?
Don Kuykendall_RIP
RIP :(
No, There is Auto ISO in the P mode. You can also set a minimum shutter speed in the Auto ISO mode
Then why isn't the ISO changing when I scroll for different shutter speeds, no matter how far I go?? What do I do to make the ISO change? I know all this sounds simplistic to anyone that knows how it works, but for some reason it's got me baffled..... I just know I'm missing something very simple.
Sure, you can choose to turn Auto ISO on in P mode. The difference is in Auto mode, you cannot turn it off.
Because scrolling in P mode is selecting other combinations of Equivalent Exposure. Do you know about Equivalent Exposure?
1/125 second at f/11
1/250 second at f/8
1/500 second at f/5.6
1/1000 second at f/4
are all the same exposure, called Equivalent Exposures.
I can't believe I typed that backwards at first.
The same exposure does not need, and cannot use any ISO change.
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Sure I know about Equivalent Exposures. That's not the issue. Auto ISO is the issue. You say that auto ISO can be turn on or off in P mode, but you say that it doesn't do anything. So, why would you turn on auto ISO?? That's just a little confusing. What am I missing?? I would think that if you scroll the shutter speed past the lower limit of the aperture, the ISO would start increasing to keep the exposure correct.
I didn't say "Auto ISO doesn't do anything". The meaning was that if we are only scrolling to choose Equivalent Exposures, there is no need for Auto ISO to do anything, no way it is needed. Scrolling P mode combinations is all the same exposure (Equivalent Exposures), but simply with different combinations of shutter and aperture (which are still Equivalent Exposures).
If Auto ISO were to change, then we would need some other different exposure.
P mode cannot scroll shutter speed past the limit of maximum aperture.
Turning on Auto ISO may help P mode find the right exposure when the light is low, but once found, scrolling is just different combinations of Equivalent Exposures at that same ISO.