James Markus wrote:
Ray,
Just wanted to ask why the 12mm tube on a lens that focuses down to 10-11 inches with CRC (Close-Range Correction) builtin? How does it effect DOF and the bokeh?
Jim
pbraymond wrote:
A trio sampling of Cutleaf Toothwort with the 28mm f2.8AIS on a 12mm tube. Some funky bokeh, but I typically struggle between getting enough depth at the main focus point vs keeping it wide open for smoother bokeh.
Jim, I use the tube to get even closer than the already close focusing bare lens. The flowers are less than 0.5" in size, and I wanted to get in really close. I need to pick up the PK11a for a shorter length tube as there were some shots I did not take due to the shadow of the lens being in the picture. Going to the PK11a will let me back off the distance by about an inch vs the 12mm tube.
I'm not sure as to DOF and bokeh impacts, I'm sure there are articles available that I can search for, something else on the list. I'm pretty sure the close I get the lesser the DOF.
