On page 24 of his book "Nikon D3100 Digital Field Guide", J. Dennis Thomas includes an image of the non-Live View Screen (the default one with the aperture/shutter display on the left). In the centre of this screen, just under the numerical readout of the shutter speed and the f-number, is a horizontal scale from + to- showing either the exposure metre or the Electronic rangefinder (depending on the mode of operation.
My camera is set to Aperture Priority in the big knob on the top of the camera. The Rangefinder is set to on In the Setup Menu, and the (kit) lens switch is set to Manual for focus (and, as expected, the two non-Live View screens show MF, greyed out). If I look through the viewfinder I can see at the bottom the rangefinder scale which consists of a series of vertical bars from left to right. These change to only two bars when the object is in focus, and I have tested it and the object is in sharp focus.
However, the Rangefinder scale never appears on the screen (and neither does the Exposure Meter when in the appropriate camera mode) as described in the book. (Actually it is odd that the book shows the rangefinder on the non-Live View screen when you can't see the object!
Is it possible to get the Rangefinder on the *Live View* screen, and if so, how?
The reason why I would like this is because I use the camera for product photography, on a tripod set at table-top height and it is very awkward to squint through the viewfinder without sitting on the floor! (Although there is an attachment which allows seeing the viewfinder by looking down, at £43 and up.)
#1. "RE: D3100 Rangefinder Display on Screen" In response to Reply # 0
You shouldn't need a rangefinder in LiveView. Use the + button to enlarge the image. The image will pop in and out of focus and it's quite easy to get perfect focus.
However in LiveView I don't know why you want to use manual focus, especially with the kit lens that has an extremely short focus throw. I only manual focus in LiveView when I'm using a manual focus lens.
If you do a lot of desk top photography where looking down is the most comfortable position, you really want one of the D5000 series bodies with the articulating screen. It makes LiveView so much easier under those conditions.
#2. "RE: D3100 Rangefinder Display on Screen" In response to Reply # 1
I don't use the Live view except when taking a movie with my D3200. I'm not that steady holding camera (handheld) I've the range finder display in the D3000 it was really dark you could see obvious changes. Both my D3200 The range finder is so thin and faint it's worse than useless. I can understand some reasoning. The D3000 used a 9 point range finder. The D3200 use a 16 point or 20 point system. But I don't mind the darker range finder.