Focal reducers and speed boosters aren’t always perfectly tuned for infinity focus, but there is an easy fix. You can find a few descriptions of the process in various forums around the internet, but the above video best describes the process. Basically, you have to find the screw/s on the reducer/speed booster that allows you to adjust the rear element. Once you do it would be best to mark the original position so you can return to the stock adjustment if necessary.This shouldn’t be necessary for the majority of adapters/lenses, but some combinations might require adjustment and if you bought a reducers/booster for a specific lens it’s worth taking the time to tune the adapter yourself if it doesn’t work 100% out of the box. This method could also be used for extreme Macro work.
This shouldn’t be necessary for the majority of adapters/lenses, but some combinations might require adjustment and if you bought a reducers/booster for a specific lens it’s worth taking the time to tune the adapter yourself if it doesn’t work 100% out of the box. This method could also be used to add Macro capabilities to a lens if you want to experiment.