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xsitar
07-06-2009, 10:36 PM
Hey
I'm wondering hat the easiest way is to achieve DOF in a window reflecting things?
Right now the window is reflecting the other side of the room inside but it's all sharp and clear.

How do you utilize DOF when not pointing in the actual direction with your camera but when stuff is reflected in such surfaces like glass?

Thanks in advance

ThE_JacO
07-07-2009, 12:13 AM
In first place DOF means depth of field, not blurring.
A shallow depth of field means there will be things in the scene that are out of focus, and those will be blurry, but dof itself doesn't mean blurry.

Out of focus also does NOT apply to reflections of an object that is oof if the reflecting object is in focus.
If something that's far and out of focus is reflected in an object near you that is not oof, then it's normal that the object won't be blurred. Reflections are like an image on that object, and the oof blur is determined by distance from the camera.
You don't want blurs on a crispy in focus item just because the reflectees aren't in focus, it would make no sesne.

Jesse-Irvin
07-07-2009, 05:22 AM
Jaco I'm not sure I understand your response. I could be wrong but I'm not sure you get the question. In real life I can point a camera at a mirror and focus on various object in the mirrors reflection, in fact it's been used in cinema a lot.

A camera in real life doesn't know the difference between a reflection and the real thing.

If this is what the OP is asking about it's something I also am wondering about and have not found a solution to.

ThE_JacO
07-07-2009, 05:41 AM
Jaco I'm not sure I understand your response. I could be wrong but I'm not sure you get the question. In real life I can point a camera at a mirror and focus on various object in the mirrors reflection, in fact it's been used in cinema a lot.

A camera in real life doesn't know the difference between a reflection and the real thing.
Sorry, made a mess of this in the reply and in reading the question.
Yes, in real life reflections will obey photon travel distance, in 3d they are basically treated like something plastered on the surface introducing dof inconsistency.

If this is what the OP is asking about it's something I also am wondering about and have not found a solution to.
In some engines spinning camera tricks will do, but the cost is usually pretty high.
Haven't tried with mray.

Jesse-Irvin
07-07-2009, 06:01 AM
spinning camera tricks are definitely the only thing I can think of but I haven't played at all with physical camera lens shader depth of field or anything so there may be a solution there. sadly much like spinning the camera these solutions can be pretty costly not to mention how slow it can be to tweak dof in a camera lens shader instead of in post.

Mic_Ma
07-07-2009, 12:18 PM
A reflected image (on a plane mirror) looks like it's behind the mirror. I think it was the first thing I learned in highschool optics.

Just blur it in post, you probably don't need detailed dof.

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