a really noob question

[timor]

If you want more DOF bump up ISO or add light. There is no other way.

How this is increasing dof ?

It increases DOF by allowing you to use a smaller aperture. You could also keep ISO down, use a small aperture and keep your camera on a tripod to allow long exposures (which is my preferred technique).

www.johns-old-cameras.blogspot.co.uk

That's the sort of explanation, which was missing from MCAP.. post. Are there any other methods of increasing dof ?

Actually, there is more you can do:

A shorter (wider) lens, and increase the distance from your subject to the camera.

So four things to increase the DOF.

Another; use a camera with a smaller sensor, such as a cell phone camera. (Which usually has a wider lens as well.)

Or, if you rich enough and own tilt-shift lens you can use Scheimpflug principle.