D70(S) P vs A mode?

Okay, this may be a stupid question but what exactly is the difference between the P and A

modes on the D70(S)? In P mode the user scrolls with the thumb wheel through f stops and

the camera determines shutter speed. How is this any different from A mode? I suppose I

should have run into this question with my F100 since the behavior of these modes seem to

be the same but I always use it in full manual mode, never in P or A. Any clues? Thanks!

IMHO, the main difference is that in P mode you can decide whether you want to use the build-in flash or not. In A mode it does so automatically.

In almost any camera these days, P is the Program mode where the camera determines both aperture and shutter speed initially, and lets you change the combination by rotating the wheel. At any setting the camera will try to ensure you get a proper exposure for the lighting available. When you rotate the wheel one way the aperture increases and shutter speed decreases, and vice versa.

 

A is aperture priority: The camera will only vary the shutter speed automatically. If you set a narrow aperture camera will not widen it for you if there is not enough light. Canon calls this setting "Av".

 

Simalrly S is shutter priority (Tv on Canon cameras), the camera will not alter the shutter speed you select, but will only try to vary the aperture to get a proper exposure.

 

Hope that helps.

 

-hash

<BLOCKQUOTE><I><B>Chris Hughes, jul 10, 2005; 03:29 a.m.</B>

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Okay, this may be a stupid question but what exactly is the difference between the P and A modes on the D70(S)? In P mode the user scrolls with the thumb wheel through f stops and the camera determines shutter speed. How is this any different from A mode?

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Yes, in that very limited context, both modes operate similarly (this also applies to the "S" shutter-priority mode, as well).  But there is more to it than that.

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In either "A" or "S" mode, whatever value you currently have selected for the aperture or shutter, respectively, is effectively "carved in granite", and the camera will vary ONLY the complimentary parameter in response to changes in light-level.

 

In "P" mode, the camera will vary *both* aperture and shutter speed in response to changes in light-level, in an attempt to maintain not only correct exposure, but also a "reasonable" combination for "typical" conditions.  See the chart on Page 78 of your D70 owners manual, for some samples of the curves it uses to juggle this trade-off, which also vary depending on what sort of lens is mounted (the manual is not completely clear on this last point, but I *think* it's taking focal length into account, in an effort to maintain "hand-holdability").  You can still override the camera's "suggested" values with the Command Dial, just as in the "A" and "S" modes; the difference is in where the "suggestion" *starts*.

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<BLOCKQUOTE><I><B>Asaf Tzadok, jul 10, 2005; 04:53 a.m.</B>

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IMHO, the main difference is that in P mode you can decide whether you want to use the build-in flash or not. In A mode it does so automatically.

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I do not believe that is correct.  Perhaps you're thinking of the "AUTO" mode (which is not the same thing as the "A" mode)?

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Jay, you are right. I thought "A" is Auto mode.

Thanks Jay. That clears things up. Now I see why I never use the P mode. Sounds like a lame

compromise between Automatic and Manual.

Chris, I wouldn't call "Program mode" lame. When I was learing I used "P" mode alot. It gave me a starting point to work from. As I became better at visualizing the result I started using "A" and "M" more often. I still use "P" mode when shooting rapidly changing situations which don't give me time to visualize. As my skills grow I will most likly use "P" less in these situations also.

Lame might not have been the best choice of words. It just strikes me as a compromised

version of A and or S modes that doesn't quite make it to P&S Auto. I mean, based on the

replies here and my subsequent experimentation with P mode it seems to me that it's a way

to achieve results that one might just as easily achieve with A mode and exposure

compensation. So, yeah. I see the usefulness of it. I guess you could consider it "advanced

auto" mode?

I shoot A alomost 90% of the time. I like it because it geves me the flexability to chose a faster shutter speed or smaller f stop with just the turn of the wheel,without thinking of the consequences.

 

If there is not enough light the 70 just slows down or opens up. When I want to nail the shutter speed then it is S mode. Same for F stop.

 

Am I evil?

 

Errool

That's how I shoot too. A mode is what my camera is in almost all the time.

I am surely evil, I always shoot P. I frankly don't see the advantage of A or S unless someone wants to blow the occassional hurried picture accidentally. I set the front wheel of the D70 to exposure compensation in P mode for additional control, and that's enough to give me all the accidental wrong exposures I need.

:-)

 

As I see it, P gives you the full control that S or A can give but in a less error prone way.

 

-hash

The problem with P mode is that it has a tendency to choose too long exposure times to get adequate protection from camera shake in hand-held photography. I use A, M, and S but not P.

 

I use the M mode typically when shooting still subjects, or backlit people. For general people photography, I choose S with a fast shutter speed when there is ample light. When there may not be enough light for good results at my preferred shutter speed, I set the camera to A mode, with the aperture from f/2.8 to f/1.4, depending on how desperate the situation is.

Hey,

 

When you choose between modes, you choose an approach to reach the good exposure. I use A mode most of the time. This is because i shoot fast moving objects rarely, thus i need the full control over the DOF. That is the main point of A mode for me. DOF is a very important part of the composition, and once you have the focal length fixed, that's the aparture what controls the DOF.

 

On the other hand, if the speed of the shutter becomes crucial (i want longer expos for motion blurring, or i want a still of a fast movement), i use the contrary approach, the S mode.

 

Seldomly i also use the M mode, mainly when i have a lot of time (still life). I think i have never used the P mode and the other modes so far.

 

Regards,

Pabo

I tend to store my cameras in 'P' mode (those that have it, anyway) as it makes a very good 'first approximation' of an exposure for those 'grab shots'. As you say, you can twiddle the dials to get whatever reciprocal pair you need.

 

For more deliberate shooting, I tend to choose 'A' mode to control DOF.

 

One point not mentioned is how the displays work with flash in either mode. In 'P' mode, the camera/flash system makes some decisions about flash vs. ambient and simply shows you the shutter / aperture pair it selected. In 'A' mode (on the cameras I have), the camera will still show you a shutter / aperture pair, but it will also advise you about underexposure as it pertains to the ambient light. This is an oft-asked question on this forum, "Why is it different?"

<BLOCKQUOTE><I><B>Chris Hughes, jul 10, 2005; 01:04 p.m.</B>

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Lame might not have been the best choice of words. It just strikes me as a compromised version of A and or S modes that doesn't quite make it to P&S Auto.

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Well, sort of.  This might be what you actually meant, but I would call it more of a compromise *between* either "A" or "S" mode and "AUTO" mode -- you get essentially (well, nearly) all of the control of the former modes ("AUTO" disables or pre-sets a lot of the stuff that is user-selectable in other modes), while still retaining *some* of the "goof-proofing" of AUTO.  for a variety of reasons, I tend to use "S" mode most of the time; but "P" is useful when I'm doing candids and grab shots, such as at a family social function, and want to concentrate more on capturing the moment than juggling the nuances of exposure trade-offs.

 

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I mean, based on the replies here and my subsequent experimentation with P mode it seems to me that it's a way to achieve results that one might just as easily achieve with A mode and exposure compensation.

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What constitutes "just as easily" will vary not only from situation to situation, but from photographer to photographer.  One of those "various reasons" I mentioned above is a 30+ year history of using shutter-priority AE film SLRs.  So for *me*, "S" is generally more comfortable than "A" (tho' on the D70, there's really not a huge difference in practice).  YMMV.

 

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So, yeah. I see the usefulness of it. I guess you could consider it "advanced auto" mode?

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In a way.  But really, it's closer to "slightly idiot-proofed 'A' or 'S' mode".

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Dunno 'bout the D70 but my D2H works great in "P" mode. I use it there 75% of the time. If the shuter speed is too slow just twirl the thumbwheel a notch or two and it will bias the EV for a faster shutter speed. Twiddle it the other direction to bias it toward shallower DOF. Easy, fast.

 

I use "A" and "M" modes almost solely when shooting with my older AI and AI-S lenses. Which is quite a bit.

 

I don't use the "S" mode too often but it's helpful for action shooting in really bright light.