in 4.13,the DOF’s focal region seems to be broken on real ios metal devices,whichever value I set will not make the places far away blur.However,every seems ok in mobile es3.1 preview.And I have changed to use the Gaussin DOF.The BUG have been tested on iPhone 6plus.iphone6s.
I was able to confirm what you are reporting and have gone ahead and entered a bug report for the issue. You can track the issue following the link below on our new Public Issues Tracker.
Once the issue has been addressed by our engineers, the fix will be added to the release notes for fixed issues within an upcoming full engine or hotfix release.
Let me know if you have further questions or need additional assistance.