how accurate is the dof in reflections?

[irwit]

Hi all

I'm setting up a shot where 90% of the shot is a mirror and I am focusing on something through the reflection. However it doesn't seem to be focusing as I would expect. eg. to focus on the specific object in the reflection the focus point distance should be the distance from the camera to mirror plus mirror to point on the object I want to focus on.

Instead I am just getting a hazey focus point on the object but my distance is no where near correct and the object is no where near sharp?

Ive tried animation the focus point to find where is becomes sharp and then kept refining using this method but there doesn't seem to be a point where the object in the reflection is being focused on correctly.

Is there a setting I need to change to help improve this?

Any help much appreciated

Thanks

Will.

[vlado]

The V-Ray DOF is accurate. Is the mirror curved?

Best regards,
Vlado

[RE:FORM_STUDIOS]

Double check your smoothing groups, if you haven't already!

[irwit]

The mirror does have a slight curve yes, I hadn't noticed this before though. Does this change anything?

[irwit]

Double check your smoothing groups, if you haven't already!

It is CAD data so im out of luck on that front, shouldnt be too much hassle to remodel though. Will this help?

[vlado]

The mirror does have a slight curve yes, I hadn't noticed this before though. Does this change anything?

Yes, of course. Depending on the exact curvature, it may not be possible to get anything in the mirror into perfect focus.

Best regards,
Vlado

[irwit]

Hi all,

Thanks for the help, it must of been the curve that was doing it. I replaced the mirror witha flat plane, same material, and focus was working as expected. Weird because it is actually CAD data for a wing mirror so the curve shouldn't be to the point where you cannot focus. Also I was taking pictures through an actual wing mirror and getting good results last night. maybe something in the CAd translation is making it more curved?

Anyway, problem solved/ish

Thanks again

Will

[trixian]

Add a "edit normals" modifier, select all and hit reset, then collapse back to mesh. If this doesn't help, then there is darker voodoo going on.
Remodeling is basically standard procedure on my end anyway.

[tricky]

Add a "edit normals" modifier, select all and hit reset, then collapse back to mesh. If this doesn't help, then there is darker voodoo going on.
Remodeling is basically standard procedure on my end anyway.

We had a similar issue with some cad imported windows a while ago. You need to do exactly this and it should work for you.