Fine tuning DOF of camera

[enzyme69]

I never quite understand this.

While Blender DOF focusing go to 0.01 sometimes to get the right result. Cycles IPR is pretty fast. However, converting to Renderman, I found it really hard to focus on X object.

Is there a tutorial solely talking about in camera DOF?

[enzyme69]

Above, I tried fro 1.4 to 2.8, all the way to 28 and still that screw in the center is not in focus.

[enzyme69]

Actually, object focusing is wrong. Distance measurement and plugin the value, following the onscreen realtime result is better.

[jdent02]

Are the screws modeled to real world size? That's one thing to keep in mind, the dof values are the same as a real camera. So if you're objects are modeled large it will take a very low fstop to see any blur. Also I wouldn't put too much faith in the realtime dof accuracy. It's meant as a quick effect for opengl renders, not an accurate preview (unless you turn on high quality mode).

Sent from my iPhone

On Dec 5, 2016, at 5:56 AM, Jimmy Gunawan notifications@github.com<mailto:notifications@github.com> wrote:

[screen shot 2016-12-05 at 22 55 23]https://cloud.githubusercontent.com/assets/3952687/20884202/f3a9f0cc-bb3d-11e6-83c6-e0a31f646767.png

Actually, object focusing is wrong. Distance measurement and plugin the value, following the onscreen realtime result is better.

- You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHubhttps://github.com/bsavery/PRMan-for-Blender/issues/412#issuecomment-264836427, or mute the threadhttps://github.com/notifications/unsubscribe-auth/AM5RFPeks6SnP0QAivbf-IrucYVC3hV1ks5rE_vpgaJpZM4LEH_s.

[bsavery]

What's your focal length? I think that might be part of the issue here.

On Mon, Dec 5, 2016 at 4:47 AM, Jon D notifications@github.com wrote:

Are the screws modeled to real world size? That's one thing to keep in mind, the dof values are the same as a real camera. So if you're objects are modeled large it will take a very low fstop to see any blur. Also I wouldn't put too much faith in the realtime dof accuracy. It's meant as a quick effect for opengl renders, not an accurate preview (unless you turn on high quality mode).

Sent from my iPhone

On Dec 5, 2016, at 5:56 AM, Jimmy Gunawan <notifications@github.com< mailto:notifications@github.com>> wrote:

[screen shot 2016-12-05 at 22 55 23]https://cloud. githubusercontent.com/assets/3952687/20884202/f3a9f0cc- bb3d-11e6-83c6-e0a31f646767.png

Actually, object focusing is wrong. Distance measurement and plugin the value, following the onscreen realtime result is better.

- You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHubhttps://github.com/ bsavery/PRMan-for-Blender/issues/412#issuecomment-264836427, or mute the threadhttps://github.com/notifications/unsubscribe- auth/AM5RFPeks6SnP0QAivbf-IrucYVC3hV1ks5rE_vpgaJpZM4LEH_s.

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-- brian.savery@gmail.com 508-274-8700

[enzyme69]

The screws are not modeled to real world size. They are quite big and if Blender default is in meter, and if the unit is affecting it, then that is one factor I need to consider.

So in original setup, I just assign an object as "Focus Object". I assume that will just work with depth.

Focal Length is 90. I never changed it.

The thing that works for me is: Not to use eyedrop and Object Focus, but use distance and use 3D view DOF checker.

I do wish the Object Focus Eyedrop to work. 😑 But I will have to test it on different scene.

[enzyme69]

Result with proper focusing.

[bsavery]

Any chance we could play with a scene?

[enzyme69]

@bsavery Let me post it into DropBox.

[enzyme69]

Here you go: https://www.dropbox.com/s/4jibr7fyphw2bvq/bolt_scene_Dianoia_018_prman.blend?dl=0

CREDIT: Original "Bolt" 3D FBX Artwork and Layout by Genichiro N. via Twitter

I got his permission to render test his layout made in Maya, ported to Blender by me.

[bsavery]

I think it might be that you're using a very long focal length fairly close to the object but I think we're doing the right thing here. (and very bright lights with very reflective screws) its just very touchy with these extreme settings. I'm seeing about the same amount of DOF as with Cycles (if you use the cycles DOF vs radius). With both set to 5.6 I see about he same amount. And when switching to 12 for DOF the other objects come more into focus. Just to be clear, you original question was about the amount of area "in focus" I think. Like I said that might be a bit twitchier in terms of settings with longer focal lengths. But I do feel it's correct.

[enzyme69]

@bsavery If Object In Focus is on, we get blur though? You mean the lighting also affect the focusing like in real world?

[enzyme69]

I will test again with simpler setup but you can close this issue reporting if you think it's correct. Cheers~

[bsavery]

Yes, well the object in focus dropper, I think it focuses on the "origin" of the object, which in extreme cases might be too fine with wide Fstops.

And actually I think what I meant to say was that the focusing effects the lighting (i.e. bokeh etc) like in the real world.

On Mon, Dec 5, 2016 at 4:45 PM, Jimmy Gunawan notifications@github.com wrote:

I will test again with simpler setup but you can close this issue reporting if you think it's correct. Cheers~

— You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub https://github.com/bsavery/PRMan-for-Blender/issues/412#issuecomment-265026284, or mute the thread https://github.com/notifications/unsubscribe-auth/ABzffIyiXq2U4JnNAr1iu5gdDUJ7N_G7ks5rFLAngaJpZM4LEH_s .

-- brian.savery@gmail.com 508-274-8700

[bsavery]

And therefore making it harder to see the blurring.

On Mon, Dec 5, 2016 at 4:48 PM, Brian Savery brian.savery@gmail.com wrote:

Yes, well the object in focus dropper, I think it focuses on the "origin" of the object, which in extreme cases might be too fine with wide Fstops.

And actually I think what I meant to say was that the focusing effects the lighting (i.e. bokeh etc) like in the real world.

On Mon, Dec 5, 2016 at 4:45 PM, Jimmy Gunawan notifications@github.com wrote:

I will test again with simpler setup but you can close this issue reporting if you think it's correct. Cheers~

— You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub https://github.com/bsavery/PRMan-for-Blender/issues/412#issuecomment-265026284, or mute the thread https://github.com/notifications/unsubscribe-auth/ABzffIyiXq2U4JnNAr1iu5gdDUJ7N_G7ks5rFLAngaJpZM4LEH_s .

-- brian.savery@gmail.com 508-274-8700 <(508)%20274-8700>

-- brian.savery@gmail.com 508-274-8700

[enzyme69]

I made a simpler scene and you right seems like Object Focusing is working correctly in PRMan when using enough light. Maybe it's case of too physically correct 🤓

Simpler Blender scene for DOF: https://www.dropbox.com/s/zitkxmivksf0yvp/focusing_prman_cycles_003.blend?dl=0

Will study more. Thanks~