# Rhino 6 bug - focal blur

**URL:** <https://discourse.mcneel.com/t/rhino-6-bug-focal-blur/54676>\
**Category:** Rendering\
**Created:** [February 6, 2018, 11:13am UTC](https://discourse.mcneel.com/t/rhino-6-bug-focal-blur/54676 "2018-02-06T11:13:16Z")\
**Posts on this page:** 1\
**Showing post:** 40

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**Author:** ![FrankS](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/franks/32/656109_2.png) [@FrankS](https://discourse.mcneel.com/u/FrankS)\
**Post date:** [April 6, 2018, 7:07pm UTC](https://discourse.mcneel.com/t/rhino-6-bug-focal-blur/54676/40 "2018-04-06T19:07:27Z")

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I don’t know if it’s me or a new kind of bug.  
For me the focal distance and aperture settings produce unpreditable and inconsitent results.

I hope we can agree that all other things equal, identical sets of values for focal distance and aperture should always result in the same visual result.

This is not the case in V6.4 RC1 in my experience. I fiddle around with (only these) two parameters. Upon hitting enter, the blur effect changes. Then, when I change these parameters back to the settings I had before (again all other thing equal) the image is completely different (like no blur vs blur-only). Feels buggy to me.

Can anyone confirm this kind of behavior?

UPDATE:  
Seems like there is similar glitch in Cycles to the one in this thread :

> [@Bug report: Light intensity and color settings ignored in cycles](https://discourse.mcneel.com/t/bug-report-light-intensity-and-color-settings-ignored-in-cycles/59802/3):
>
> Thanks for checking, Nathan. The file was V5 before, I imported it into V6.4 Hence, it was never opened in V6.3 As I said before (in the bug report about zombie lights), these behaviors seem hard to reproduce and light system seems quite shakey to me. If I change a few parameters forth and back (exactly), I seem to end up with completely different results. Barely visible light vs brutally overexposed after closing and reopening a file. Trying to setup / strip down a test file for you, I see…

Blur results are different before and after switching to shaded mode and back to Cycles.

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