[chris_muc]

I have a strange issue with my canon ef 40 STM while focusing manually.

 

You can see the issue on 200% part of picture here:
https://dl.dropboxusercontent.com/u/1626...mages.html

you need to roll over the image or out to see the difference.

 

The picture is moved slightly. This move was cause depending if I set the focus turning MF ring from infinity to close, or the other way round.

 

I have checked on 50 1.8 and EF-S 18-55IS and such situationi does not appear.

 

Is my lens faulty?

 

thanks,

Chris

[Klaus]

I'd say that this is not unusual. AF lenses have some 'play' in the focus group. Sometimes more, sometimes less. 

The focus group has to have low friction due to the AF motor. This is sometimes a side effect.