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View Full Version : Looking for help with matching real world camera Focal Length.



4dartist
08-22-2013, 12:50 PM
A client gave me images from a Canon EOS 5D Mark III camera. The Focal length changes from picture to picture. I was hoping to find the right ratio so I can figure out what Focal length to use in lightwave. I know this gets very tricky because of different sensor sizes and something about cropping sensors etc..

Does anyone have this skill that can help me do a conversion? For example here is the data from the photograph.

Dimensions 5616x3744
Device Make: Canon
Device model: Canon EOS 5D Mark III
Color Space: RGB
Color profile: Adobe RGB (1998)
Focal Length: 40
Alpha: No
Red eye: No
F number: 10
Exposure time: 1/200

I don't know if the data in the image uses a 35mm equivalent or the actual focal length. I found that the sensor is 36mm x 24mm. I also can't figure out if lightwave uses 35mm equivalent or how to figure it's 'sensor size'. I'm pretty confused at this point.

RebelHill
08-22-2013, 12:59 PM
It records the actual focal length of the lens. Since its a 5D, its full frame... so... 35.8 x 23.9mm which is basically LWs 135 preset.

4dartist
08-22-2013, 01:16 PM
Thanks RebelHill for responding. Can you explain what you mean by LWs 135 preset? I can pick Canon SLR > EOS 5D in a Real Lens Camera but need to pick a lens. I see EF 135mm f/2.8 soft focus. Is that what you mean? Since it's full frame can I just leave the Focal Length at 40?

Thanks again for your help.

RebelHill
08-22-2013, 01:23 PM
If ur using real lens, sure, just enter the length as is... Id presumed u were using standard camera, in which case you set the frame drop down to the "Size 135" option.

4dartist
08-22-2013, 01:40 PM
If ur using real lens, sure, just enter the length as is... Id presumed u were using standard camera, in which case you set the frame drop down to the "Size 135" option.

I may be losing my mind. Where is the "Standard Camera"? In 11.5 I see the following: Advanced, Classic, Ortho, Perspective (which I usually use), Real Lens, Shift, and Surface Baking. Of all those cameras I cannot find an option that lists 'Frame' as a drop down or any drop downs that say "Size 135". :/

I can use the Real Lens option for now, but I was planning to use the Perspective Camera type originally.

RebelHill
08-22-2013, 01:52 PM
perspective (I meant standard as opposed to fancy real lens/anvanced/etc)

4dartist
08-22-2013, 02:02 PM
Ah ok thanks! I see the option now.

Thanks for all your help!

RebelHill
08-22-2013, 02:09 PM
no worries

Lewis
08-22-2013, 03:24 PM
Why not use Real Lens Camera option "load form image" and then LW will set you what it reads from Metadata of Image you got from client (even the DOF so be carefull if you don't want DOF/Motion blur)?

BokadCastle
08-22-2013, 05:00 PM
Serling knows cameras - post him the question.
http://forums.newtek.com/showthread.php?132857-Canon-5D-Mk-III-for-effects-work&highlight=serling