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Blurry image help

Posted: Thu Aug 18, 2005 7:25 pm
by MarkM
Hello,
I have been getting a lot of blurry results. I'm thinking it has to do with the camera being out of focus/DOF issues.

I have been using a 50mm lens length
Shutter 200
F Stop 5.6
Film width 24
Film Height 24

units Feet

Attached is my image and a screen shot of my camera, could you tell me if something is wrong?

17 samples reached
Image


camera
Image

Thanks,
Mark

Posted: Thu Aug 18, 2005 7:38 pm
by Thomas An.
Mark,

The camera target indicates the most sharp area of the image. Right now your camera target is behind the building. If you move it closer to the facade your image wil come to focus. Also, you may try using the placeTarget command and snap on some geometry at the front of the building to help.

Posted: Thu Aug 18, 2005 8:34 pm
by sidenimjay
and more than anything else . . . . . .


check your scale . . . . . is your house 30 inches tall or 30 feet??


scale is generally the problem when you cant focus your scene no matter what you try . . . .

Posted: Fri Aug 19, 2005 12:47 am
by MarkM
Thomas,
Thanks for the reply. I have a few questions; does the distance between the camera and the camera target matter? Is there a rule of thumb on how far the target should be from the model?

Sidenimjay,
Thanks for the reply. My model is to scale.

Thanks,
Mark

Posted: Fri Aug 19, 2005 2:13 am
by Thomas An.
Hello Mark,

Yes the distance from camera to target will affect how wide the Depth of Field is.
You can calculate the near and far limits by using the calculator at the bottom of this page http://www.dpreview.com/learn/?/Glossar ... eld_01.htm

You may also find this little Rhino-script usefull for Camera and target manipulation as well as visualizing a number of camera locations in your scene. CameraLine.rvb

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Image

Posted: Fri Aug 19, 2005 8:09 am
by tom
Thank you for this great diagram Thomas!
As always, your whitepapers rock! :D

Posted: Sat Aug 20, 2005 8:38 pm
by ivox3
.....that may be the simplest & most eloquent explanation i've ever seen explaining the basic principles of DOF. Simple and Sweet.

Nicely done...

Posted: Sun Aug 21, 2005 4:12 am
by MarkM
Thomas,
Thanks very much for that illustration. It is very easy to understand. I always admired your work. I think that illustration should go into the user manual. :wink:

If I'm not mistaken Thomas I remember reading something that you do patent drawings? If so, do you mind me contacting you in the near future when I need some done?

For some reason I was always under the assumption that DOF was the blurry part of the image. I'm glad I got that cleared up.

My understanding now is that the F-stop, lens size and focus lock distance will control the range of the most focus/DOF area. Correct me if I'm wrong.

You can see my new render here if you would like to comment on it. :D

Thanks again,
Mark

http://www.maxwellrender.com/forum/viewtopic.php?t=6017