Is there a 1.8g? The 50mm f/1.4 G lens is AF-S and will autofocus on the 3100. The 50mm f/1.8 D is an AF but not AF-S lens and will not AF on the 3100, but it will manually focus with metering and focus confirmation.
The biggest difference with D lenses is using flash and with subjects occupying only a small part of the frame. The distance information lets the newest cameras get the correct flash exposure, while with non-D lenses the camera has to guess harder.
AF-D work the same as AF lenses, even in difficult flash situations. The only difference I could see was if I had a backlit shot with an object in the foreground. If you focus on the foreground the image attempts to expose the flash for the foreground object, and if you focus on the background, the foreground object becomes too light
Another improvement is if you want to photograph straight into mirrors. Without a D lens you'll get underexposure because the image of the flash in the mirror fools the meter into underexposure. With D lenses you'll get a properly exposed image of a bright flash. I've expended film on this foolishness so you don't have to.
btw I completely forgot what the f.18 <-- meant can someone explain please simple and straight forward
can someone explain please simple and straight forward
... The lower that number also means more bokeh = more background separation for your subject.
it's the age you are allowed to vote for your president in the US, if you are registered - same her in germany, if you like to be elected here in germany, you need to be 21