Jacques, I am not sure but I think that the DOF will always be related to the size of the object related to the size of the sensor. Meaning that extension tubes or close up, for a specific size of the object on the sensor .. you will always have the same DOF = very shallow.
The only way to go would be to use a camera with a smaller sensor 5 not a reflex one) that has macro capabilities and can focus very vlose to the object.
This is my understanding.
Lionel |