I have been using extension tubes for my macro work for a while now and I feel I have a good grasp of their idiosyncrasies. Today I wanted to photograph the tiny flowers that we have growing in our indoor garden. I decided to use my tripod today as I wanted to get fairly close in and I knew camera shake was going to be a problem. The tubes, though good at getting the magnification, cut down a fair amount of the light moving through the lens. This causes a few challenges. The first is the need to use higher ISO's in order to hand hold at a fast enough shutter speed. Second the extreme magnification also magnifies camera shake thus requiring a tripod to stabilize the camera. Third there is an extremely shallow depth of field. Finally one has to move the camera to help refine the focus.
These issues are difficult and can be overcome with patience and an understanding of what options one has available. While I have handheld the tubes this has required ISO's in the 3200 range which does affect the sharpness. Today I wanted as much sharpness as I could have so I wanted to stay at 100 ISO. Using a tripod would give me the stability I needed and allow me to work at f22 to get the maximum DOF. Shutter speed was reduced to 0.3 of a second and I used a cable release to trigger the camera. Below are two images of the set up.
The first shot here is of a strawberry flower covered with pollen.
This image is a marigold flower and the pistil and stamen at the center. I found it both colourful and intriguing.