Generic Extension Tube On Nikon D3100 Kit Lens

If you try to use generic extension tube for your Nikon D3000/3100 with AF-S DX Lens or kit Lens,
The result of photo will be too dark, except you use the slow / long speed.
The problem is : we can't set the aperture size, it is too small.

To set the aperture size I have a little trick,

Take a small size of slipper/rubber or something like that, use scissors to cut it
Open/ remove the Lens from Camera body
Put rubber/slipper to the part of aperture controller of the lens
See and set  the diaphragm to make it open to have right aperture size
Put/connect the extension tube to the lens, and then connect to the camera body
Set Camera selector to the M (manual) shoot
Set Focus to M (Manual)

Check out the video for more details :

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