Underwater Beam splitter rig

[Ross Isaacs]

Does anyone know if the Liquid Pictures underwater beam splitter rig has major problems with reflections and how do they overcome these problems? Is the reflection problems mainly when this kind of rig is used in an underwater studio situation with light sources illuminating subjects and sets or is reflections a general problem which can be over come by the use of french flags etc????

[Johnny Johnson]

Further question to this, we have a customer building their own underwater 3D mirror rig for 1 red and one epic. Can anyone advise on whether having cameras converge (either/or) cause reflections off the glass at the front? The glass will be flat rather than a dome to try to ensure images are identical.

[Ross Isaacs]

Further question to this, we have a customer building their own underwater 3D mirror rig for 1 red and one epic. Can anyone advise on whether having cameras converge (either/or) cause reflections off the glass at the front? The glass will be flat rather than a dome to try to ensure images are identical.

I don't see any way you could use dome ports with a beam splitter rig underwater.....a pity because I tend to shoot wide underwater. Apparently even with flat ports the reflections are a real pain with a beam splitter rig underwater because of all the reflective surfaces.

[Jason Goodman]

I have very limited underwater experience and don't want to speak out of turn but would certainly recommend you at least take the precautions you would with a beamsplitter on land. Make sure the mirror can properly handle specular highlights and reflections off of glass, metallic, organic and wet surfaces. For the best results, filtration like that employed in the 21st Century 3D BX3 should be used. Many stereoscopic issues can be seen in work shot without such precautions. I just saw Step Up 3D last night and although there were some good 3D shots in it, leather jackets, leather furniture, black hair, shiny floors and other materials all exhibited fairly objectionable retinal rivalry due to mishandling of specular highlights.

http://www.21stcentury3d.com/3d-cameras/3d-digital-cinema/

Jason Goodman
CEO
21st Century 3D New York
505 8th Avenue #1006
New York, NY 10018
212-244-8585

21st Century 3D Hollywood
3450 Cahuenga Blvd W #509
Los Angeles, CA 90068
323-799-1046

http://www.21c3d.com
jason@21stcentury3d.com

[Dave Blackham]

Further question to this, we have a customer building their own underwater 3D mirror rig for 1 red and one epic. Can anyone advise on whether having cameras converge (either/or) cause reflections off the glass at the front? The glass will be flat rather than a dome to try to ensure images are identical.

I think you will definitely need a high spec AR coating on the front port to make this work. Depends on the work its intended for but you might be better off with a side by side housing, to get anything wide could be a real problem or you'll need a very big mirror box.

Does any one yet know what minimum IO is possible side by side with Epic ? is it the body or Front element of the lens thats the limiting factor ?

Dave

[Dave Blackham]

I don't see any way you could use dome ports with a beam splitter rig underwater.....a pity because I tend to shoot wide underwater. Apparently even with flat ports the reflections are a real pain with a beam splitter rig underwater because of all the reflective surfaces.

There may be a way, we are working on it in the workshop right now.....

[Johnny Johnson]

Side-by-side is a more obvious option, but the customer wants options to cover all bases so is specifically going for automated mirror rig for a very big project.

I think the IO on the Epic will be about the same as red. The red pro lenses (and therefore others) look to be wider than the body, but I think still lenses will be smaller.

[Ross Isaacs]

I have very limited underwater experience and don't want to speak out of turn but would certainly recommend you at least take the precautions you would with a beamsplitter on land. Make sure the mirror can properly handle specular highlights and reflections off of glass, metallic, organic and wet surfaces. For the best results, filtration like that employed in the 21st Century 3D BX3 should be used. Many stereoscopic issues can be seen in work shot without such precautions. I just saw Step Up 3D last night and although there were some good 3D shots in it, leather jackets, leather furniture, black hair, shiny floors and other materials all exhibited fairly objectionable retinal rivalry due to mishandling of specular highlights.

http://www.21stcentury3d.com/3d-cameras/3d-digital-cinema/

Jason Goodman
CEO
21st Century 3D New York
505 8th Avenue #1006
New York, NY 10018
212-244-8585

21st Century 3D Hollywood
3450 Cahuenga Blvd W #509
Los Angeles, CA 90068
323-799-1046

http://www.21c3d.com
jason@21stcentury3d.com

I am thinking that with the construction of an underwater beam splitter rig it might be beneficial to have attachable variable french flags on the housing to help with specular highlights. I don't believe a side by side rig would give enough coverage for close ups and medium shots. I am thinking 18mm would probably be the widest one could shoot with flat ports on such a system....anyone think wider lenses would be possible on a beam splitter rig with a flat port?
regards
Ross