Upload & Sell: Off
| p.1 #7 · "AUTO" and "P" modes and "VR" Effect on the D7000 |
P mode and green auto are not the same. With P mode you have full control over exposure and settings. With green Auto or Scene modes, you don't.
Green Auto mode will attempt to give settings that "work"...shutter speed not too slow, ISO not too high, aperture not so open for sharp detail. It tries to select a middle ground and will pop the flash if necessary. The Scene modes apply some photographic knowledge to the process. For example, if you select sports mode then the camera will favor a high shutter speed over low ISO, enable continuous focus, and disable flash and focus assist light.
P mode is simply another exposure mode...same as A mode, S mode, and M mode. P mode does nothing more than select an aperture and shutter based on the current EV level of the scene. The program chart is in the back of the D7000 manual on page 298. For example, if the EV of the scene is 12 at ISO 100, then you'll get f/5.6 and 1/125s. There's no decision making here...you always get the same values for the same EV. What you can do, however, is use the Flexible-Program function to select other combinations that provide 12 EV (as described on page 68 of the manual.)
P mode just gives you a working starting point. If you maintain the meter on the same tone, or lock exposure, you can then select any aperture/shutter combination you want for that exposure level. And you can use the EC function to adjust exposure. So you have as much control over exposure and over which settings are used as you do in any other exposure mode...you simply have to know how your camera works.
What you're really asking about is the Auto ISO function. In regards to Scene modes, I don't know if the VR of the lens is taken into account. I would imagine that it isn't because the idea of adjusting shutter speed based on focal length is mostly useless to begin with. That's because shutter speed is usually far more limited by the subject matter. If you're shooting birds in flight you need to use at least 1/800s to freeze the birds, pretty much regardless of your focal length. You need at least 1/320 or 1/500s for most sports. And for shooting people you usually need 1/120s (1/60s at a bare minimum.) So many times the 1/FL rule (which is actually 1/FL x crop factor for crop cameras) leaves you short on shutter speed.
When using the MASP modes, Nikon's Auto ISO function is used. With Auto ISO, you specify what the Minimum Shutter Speed should be. So if you're shooting sports, you set the MSS to 1/500s. Now, while you're shooting in A mode it doesn't matter what the zoom position is, the shutter speed will never go below 1/500s, and ISO is adjusted to make up the difference in exposure.
But then lets say you're shooting people sitting around at a picnic with your 70-300mm VR. You can set the MSS to 1/120s and know you'll get sharp images without an excessively high ISO. The reason is that the even if you zoom in to 300mm, the camera will not suddenly decide that you need a shutter of 1/500s due to your focal length. The VR system will keep the image sharp, and the Auto ISO will make sure that you have at least the minimum shutter speed required for the subject matter.
The D4, D800, and D600 recently got an "auto" option for the MSS, so that shutter speed can be based on focal length. I guess it might be useful if you have some non-VR glass of longer focal lengths. Considering that it was a simple function that could have been implemented years and years ago, I think Nikon simply added the "auto" function so that idiot reviewers would finally shut the hell up about the Auto ISO not being based on focal length. I certainly can't see such a function being useful because you must still consider the shutter speed requirements of the subject.