All none DSLR's will give you a large depth of field even at an aperture of 2.8 unless you use macro mode.Fuji Film S9100..

I think most P-modes just try to maximize Shutter speed, and set the Aperature accordingly after the shutter speed is set to get the proper metering. If you want to control the DoF, use Aperature-priority mode..

Leehttp://leem.smugmug.com..

Marcus305 wrote:.

I understand that a smaller f-stop number (larger aperture) willresult in a shallower depth of field, while a larger f-stop number(smaller aperture) will result in a deeper depth of field..

I have spent my entire life using a 35 mm P&S film camera and havejust purchased a Panasonic FZ8. My question is this: When I shootusing the automatic setting ("P"), how does my camera know how deepa depth of field I am looking for?.

Well, it doesn't. Cameras aren't quite that smart yet .

Or is just a function oflighting from the camera's standpoint? For example, if it is abright sunny day and I am taking a landscape picture where I amlooking for a deep depth of field, how does my camera know to picka high f-stop number (rather than a lower f-stop number with afaster shutter speed)?.

Probably varies from manufacturer to manufacturer, but I would guess it goes for a minimum shutter speed first, then sets an appropriate f-stop..

Since I do not necessarily expect to be able to tell what is infocus using the LCD display, it seems that I have to rely on thecamera picking the correct combination of aperture and shutterspeed..

If I know I want a deep depth of field, should I just use aperturepriority mode? Would I just pick the highest f-stop number?.

Yes, use aperture priority and start with the smallest aperture. If you don't have enough shutter speed, either increase ISO (not recommended on a point 'n shoot) or choose a larger aperture..

Mark..

As others have indicated, the camera can't know your intentions. "P" mode will use an algorithm to derive a "reasonable" combination of aperture, shutter speed, and ISO to achieve the exposure the built in meter has determined to be a "reasonable" exposure. If you want something different you need to inform the camera. You can do this in full manual or use aperture or shutter priority to fix one of the variables, letting the camera control the others. Another approach to communicating your intent, though, is to use the camera's built in scene modes. It may be that one of the modes available on your camera optimizes for great depth of field..

Other things to keep in mind: for any given aperture, shorter focal lengths yield greater DOF than longer, and finally, you can maximize effective DOF in a scene by careful choice of focus point... see hyperfocal distance..

Regards, John..

To add to other contributions..

P mode is essentially automatic, but it does sometimes let you select one of a number of exposure combinations it deems reasonable. Your manual will explain more..

A mode ( Aperture priority mode ) is semi-automatic. You tell the camera what aperture you want, it tries to find a suitable shutter speed. If you leave ISO on Auto it will also adjust ISO to try and get a suitable shutter speed. In practice, as someone pointed out already, a P&S will crank up ISO and deliver a very noisy image. For this reason try to keep ISO as low as possible, and not on auto. This is the mode for control DOF without using full manual..

S mode is semi-automatic, and you are selecting shutter speed. You don't directly control DOF in S mode. The camera calculates Aperture for you. Can be thought of as the opposite of A mode..

M mode - full manual. You set shutter speed and aperture. This is the way to force your camera to do things it does not want to do ( or which it thinks it can't ) in full or semi automatic modes..

StephenG.

Fuji S9600Fuji S5200Fuji F30Fuji E900Canon A710ISPCLinuxOS..