Does anyone hve any experience using Promaster extension tubes with Canon bodies and lenses? Do they maintain all auto functions (metering and focus) and IS individually and when stacked?
Promaster is a house brand traditionally sold at retail shops. The source and quality of product tends to vary all over the place. That being said, if a set of tubes has an EF mount then it should function. Do yourself a favor and by the Kenko extension tube set.
