Grey Focus Distance Readout?

[rlkproductions]

Hey
Sometimes when I zoom in and try to focus very close, the focus distance readout will turn grey and not get any closer. I can zoom out and get a closer focus. What does this mean?

 

[Huy Vu]

Because there's a minimum focus distance where the lens can't focus any closer.

 

[rlkproductions]

Why does the minimum focus distance change based on zoom? shouldn't focus be measured from the lens regardless?

 

[Huy Vu]

When you zoom, the focal length of the lens is actually changing. Longer zoom tens to have shorter minimum focus distance.