Program (P) vs. Automatic (A)
Jan 9, 2016 09:23:25 #
A is for aperture, not automatic. Automatic lets the camera decide the settings for all of the exposure triangle. most new photographers start in A mode, then try the P mode where you may control the ISO and let the camera set the aperture and shutter speed. once you are comfortable with ISO settings, you may want to play with the A, aperture, mode where you set the aperture and let the camera set the ISO and shutter speeds. you tube has many videos that will help you experiment with the various settings.
Jan 9, 2016 09:31:58 #
John N wrote:
I'm sure this is in the CANON manual somewhere but I've missed it. Thanks for the clearest, most concise explanation I've yet to see.
It is a good generic explanation of the principles, but you won't find exactly the same thing in a Canon manual since each manufacturer does things differently. Your Canon manual will give you the precise terminology and descriptions that apply to Canon cameras.
Might be worth a look.
Jan 9, 2016 09:35:36 #
orrie smith wrote:
A is for aperture, not automatic. Automatic lets ... (show quote)
That may be true for some camera brands, but not for all. There is no standard, universal set of definitions. Reading the manual can frequently provide a few clues.
Jan 9, 2016 11:43:55 #
According to Scott Kelby, all those settings work in the same way for the major camera brands (Nikon and Canon). In that with A you can only adjust aperture, with S you can only adjust the shutter speed and the camera sets the other two for proper exposure. With P you pick one of the basic three to adjust and the camera sets the other two. On point and shoot types S usually stands for Scene mode and you get to choose the scene. Most entry level SLRs the mode dial has several scene settings which adjust the camera for the anticipated image.
Jan 9, 2016 12:02:53 #
One thing I like about P is it remains pretty much fully automatic but I can set a single focus spot which I like for birds and wildlife. Ever try to focus on a bird in a tree and you end up focusing on everything but the bird? There are a few other things you can do in P that are not allowed in fully automatic.
Jan 9, 2016 12:07:28 #
When I shot with a Canon 7D on Auto, the camera would sometimes consider conditions to require the popup flash, whereas I wanted natural light. The answer was to use the P setting, which let me decide when to use the popup flash.
Jan 9, 2016 12:09:27 #
ruswhite
Loc: Sun Cit, AZ
The "auto" mode uses a the scenes database to determine what the image on the sensor is and sets the camera accordingly. The CPU (camera computer) uses the info on the sensor, like the contrast, and from the lens, like focus distance, and then compares it to the database to figure out what the subject is, such as People or Landscape or Action, and so on. the CPU then makes what it believes to be the best settings to get the best picture.
P(rogram) mode sets for best exposure but it can be fooled because it doesn't know what the subject is, or if the image is excessively light or dark but just assumes that the average brightness is neutral gray.
P(rogram) mode sets for best exposure but it can be fooled because it doesn't know what the subject is, or if the image is excessively light or dark but just assumes that the average brightness is neutral gray.
Jan 9, 2016 12:17:32 #
also in P you can set or use exposure comp. by turning a dial. this works very well and you can check your lcd or check your histogram. I watch an interesting program by Sam Abell and this is how he shots.
You know the old KISS ways of doing things.
You know the old KISS ways of doing things.
Jan 9, 2016 12:41:53 #
aellman wrote:
The P and A modes appear on both of my DSLRS, but I've never been clear on the difference. The manuals don't do a very good job of explaining this. Your knowledge will be much appreciated. >>>AL
If it is a Nikon A is aperture mode. Auto mode is usually green and says Auto. Higher end Nikons (e,g. my D800) do not have Auto.
Auto controls everything including ISO, shutter speed, and aperture. It tries to figure out what your image is in setting them.
Program mode sets exposure with shutter speed and aperture. You can select over the range of exposures that give the same exposure value (EV) from widest aperture and shortest shutter speed to smallest aperture and longer shutter time. You set everything else.
A mode gives you the same control and range of aperture and shutter speeds as P mode but does it by using the thumbwheel to control aperture.
Jan 9, 2016 12:43:58 #
Delderby wrote:
Well - "Program" is pretty much "Auto" so where does that leave your other (P) and (A) ? :-)
Nope. Please read your manual.
Jan 9, 2016 12:44:17 #
scsdesphotography wrote:
According to Scott Kelby, all those settings work ... (show quote)
Well, that just goes to show that people like Scott Kelby can also be wrong! Referencing sources of information is a good thing to do, but it doesn't help if the source itself is not correct.
In this case the above information is not correct for Canon.
Is this really an important issue? That's probably up to each individual to decide. If you understand the principles then you can look up the pertinent details for your own cameras.
We get back to the old computer related adages: "Garbage in, garbage out" and RTFM.
Nothing personal intended here to anyone, but there is a large amount of inaccurate information being replicated by many people in this thread, which doesn't actually help anyone very much.
If we want to discuss Lunar photography, we could start with discussions for recipies about how to make green cheese, but would that actually be helpful?
Jan 9, 2016 12:45:29 #
robertjerl wrote:
A = automatic, everything is up to the camera's processor and sensors.
P = Program (some say Professional or Preset) the sensor judges the scene, light etc and uses Presets developed by photographers for the camera company to fit that type of photo. On many cameras once you are on P the menu gives you choices of presets to pick from such as portrait, night sky, sports etc. Some have them on the dial, others have them in menu.
P = Program (some say Professional or Preset) the sensor judges the scene, light etc and uses Presets developed by photographers for the camera company to fit that type of photo. On many cameras once you are on P the menu gives you choices of presets to pick from such as portrait, night sky, sports etc. Some have them on the dial, others have them in menu.
Wrong on P. Please read your manual.
The Scene modes on some cameras are entirely different.
Jan 9, 2016 12:50:52 #
pecohen wrote:
Traditionally, P mode was thought of as an automat... (show quote)
Good point here on the ONLY difference between P, A, and S modes on Nikons.
It continues to amaze me how many people confuse P mode with Auto.
Nikon doesn't help by calling A and S autoexposure modes in the manuals.
Jan 9, 2016 13:03:04 #
to me auto is that the camera does everything and you have no control. Much like a point and shoot.
P to me is that you get to set a few things ie iso and the camera takes over from there.
P to me is that you get to set a few things ie iso and the camera takes over from there.
Jan 9, 2016 13:18:51 #
MtnMan wrote:
Nikon doesn't help by calling A and S autoexposure modes in the manuals.
This is a very minor 'nit' comment, but what is wrong with Nikon's terminology in this case? Canon is similar in this regard, although they use different symbols.
Automated exposure seems to mean that the camera has some degree of control over the exposure parameters.
In Auto mode, that frequently means everything.
In P (Program) mode, that frequently means both shutter and aperture settings, but things like ISO, focus and other things can often be set by the user, but can also be set to auto modes.
In Aperture priority mode (Av on Canon), that frequently means the aperture is set by the user and the camera auto selects the exposure by controlling the shutter speed, and things like ISO, focus and other things are usually be set by the user, but can also be set to auto modes.
In Shutter priority mode (Tv on Canon), that frequently means the shutter speed is set by the user and the camera auto selects the exposure by controlling the aperture, and things like ISO, focus and other things are usually be set by the user, but can also be set to auto modes.
All of the above are variants of auto exposure in one form or another.
Another variant of auto exposure is to set both the shutter speed and aperture manually and let the camera adjust the ISO automatically.
In fact, it generally takes a lot of work to put a modern camera under fully manual control, and in some cases it simply cannot be done.
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