Demonstrating a method for working around full auto in video mode on the T1i using a Canon EF 50mm F1.8 lens. This "workaround" allows selecting and locking in a desired aperture for specific DOF effect. ISO and shutter are still auto for proper exposure.
NOTE: One step was left out, if an aperture smaller than maximum is wanted the DOF prevue button must be held in while the lens is "unlocked" otherwise lens remains wide open.
The 50mm F1.8 and 1.6X factor from APS C size sensor gives this lens almost perfect portrait perspective for "two shots" and closeups. F1.8 aperture gives quite shallow DOF and selective forcus, this Canon lens can also be "tack sharp".
The viewfinder assembly is from CAVISION of Vancouver, Canada. The optics are 6X unlike the Hoodloupe which provides no magnification. I use both and the CAVISION viewfinder can be had in a similar configuration to the Hoodloupe, cost is almost comparable. The configuration I have with the mounting assembly runs a tad more than double the Hoodloupe price but is still less than half the price of the new Zacuto Z2