Optical fiber sandwich plate and microlens arrays for shallower DOF?

Jim Lafferty · February 1st, 2006, 06:05 PM

I'm aware of the fresnel artifacting but I'm fairly certain Bill's screen should sidestep that issue. I'll know for certain within a week. A DCX might be nice but, considering weight and length (of the adapter), I'm not sure it's the wisest choice (for me).

I do know for sure, on the other hand, based on what others have said here, that the Maxwell diffuse surface is not a completely satisfactory static solution.

Engineered diffusers -- spoke with the POC/Edmund people and their comments on this led me to believe it's probably not the best solution. I could be wrong, but... it's a $115 question I'm not sure I need to answer right away.

I have other ideas :D

Daniel Apollon · February 6th, 2006, 03:01 AM

"Lenses can be either refractive or diffractive and can be as small as 15 microns diameter. Using standard materials such as fused silica and silicon and newer materials such as Gallium Phosphide and Calcium Fluoride a wide variety of lenses can be made. Lenses can be made on one side with absolute alignment accuracies which allow each lens to be within 0.25 microns of it's ideal location and a front to back surface alignment capability that allows lenses on both sides of a substrate to be aligned to within 1 micron. Surface roughness values of 20 to 80 angstroms RMS are typical and the addition of AR coatings produces optics with very high transmission rates."
http://www.memsoptical.com/prodserv/...icrolensar.htm

"Traditionally, diffusers have been made using binary technology which resulted in a bright central zero order hot spot", significant haze, and relatively low efficiencies. Now, by applying MEMS Optical's patented gray scale production process, diffusers can be made with minimal zero order hot spots (often less than 1%) and efficiencies as high as 95%."
http://www.memsoptical.com/prodserv/.../diffusers.htm

Dennis Wood · February 14th, 2006, 02:49 PM

Daniel, any idea what function this has in an Arri camera?

Daniel Apollon · February 14th, 2006, 02:54 PM

Replacing the GG

Dennis Wood · February 14th, 2006, 07:03 PM

Let me rephrase that. How is a GG used in a film camera? Same concept as SLR?

I would assume somehow the operator is able to look through the lens while shooting, or a seperate finder is used?

I've never seen an Arri, or any other film cam for that matter, in person.

Bob Hart · February 14th, 2006, 09:43 PM

Jim.

The PCX. Is this a condenser lens with the sides cut off.? Are the Nikon viewfinder condensers separate from their groundglass screens, ie., polished on both sides? A Nikon glass might just fit below the front prism on my gadget or perhaps one each, either side of the groundglass disk.

SLR lens >> Nikon condenser-(| >> groundglass >> |)-Nikon condenser >>
prism pair >> Century Optics 7+ achomatic dioptre >> Camcorder.

Do you see this as a solution to edge falloff with widescreen images on the FX1? Is is mainly an issue when I shoot the aerial image with long lenses but is apparent with the groundglass image in certain lighting consitions.

Daniel Apollon · February 15th, 2006, 01:16 AM

Bob, depending on the camera the GG is fed either
1) Through a "light sharing" scheme, using a special prism, e.g. in Bolex RX cameras where 75% of light goes to the film and 25% to the ground glass setup.
2) Through an "in-between exposure" scheme, where the ground glass is exposed in the time lapse when the shutter is closed.
There are also more sophisticated schemes which lie well beyond my expertise.

Wayne Kinney · February 15th, 2006, 05:29 AM

I have seen the 2nd method working up close, with the light being redirected to the finder between the shutter. Because of this, the finder gives the same 'film motion' live which i thought was clever.

Dennis Wood · February 15th, 2006, 07:20 AM

It's an interesting problem I hadn't thought of. I would have guessed (and then dismissed) the image split solution as a lossy one. As Wayne has alluded, if the shutter is open for 1/48s, then at 24fps you are seeing the same cadence in the viewer as the film is capturing.

It must get interesting when frame rates are cranked.

February 1st, 2006, 06:05 PM	#16
Jim Lafferty Major Player Join Date: Dec 2003 Location: Brooklyn, NY Posts: 636	I'm aware of the fresnel artifacting but I'm fairly certain Bill's screen should sidestep that issue. I'll know for certain within a week. A DCX might be nice but, considering weight and length (of the adapter), I'm not sure it's the wisest choice (for me). I do know for sure, on the other hand, based on what others have said here, that the Maxwell diffuse surface is not a completely satisfactory static solution. Engineered diffusers -- spoke with the POC/Edmund people and their comments on this led me to believe it's probably not the best solution. I could be wrong, but... it's a $115 question I'm not sure I need to answer right away. I have other ideas :D __________________ Realism, anyway, is never exactly the same as reality, and in the cinema it is of necessity faked. -- J-L G

February 6th, 2006, 03:01 AM	#17
Daniel Apollon Regular Crew Join Date: Oct 2005 Location: Norway & France Posts: 50	Microlens arrays and diffusers with controllable hotspot "Lenses can be either refractive or diffractive and can be as small as 15 microns diameter. Using standard materials such as fused silica and silicon and newer materials such as Gallium Phosphide and Calcium Fluoride a wide variety of lenses can be made. Lenses can be made on one side with absolute alignment accuracies which allow each lens to be within 0.25 microns of it's ideal location and a front to back surface alignment capability that allows lenses on both sides of a substrate to be aligned to within 1 micron. Surface roughness values of 20 to 80 angstroms RMS are typical and the addition of AR coatings produces optics with very high transmission rates." http://www.memsoptical.com/prodserv/...icrolensar.htm "Traditionally, diffusers have been made using binary technology which resulted in a bright central zero order hot spot", significant haze, and relatively low efficiencies. Now, by applying MEMS Optical's patented gray scale production process, diffusers can be made with minimal zero order hot spots (often less than 1%) and efficiencies as high as 95%." http://www.memsoptical.com/prodserv/.../diffusers.htm

February 14th, 2006, 02:54 PM	#19
Daniel Apollon Regular Crew Join Date: Oct 2005 Location: Norway & France Posts: 50	Function of the fiber plate Replacing the GG

February 15th, 2006, 01:16 AM	#22
Daniel Apollon Regular Crew Join Date: Oct 2005 Location: Norway & France Posts: 50	GG Film camera versus SLR Bob, depending on the camera the GG is fed either 1) Through a "light sharing" scheme, using a special prism, e.g. in Bolex RX cameras where 75% of light goes to the film and 25% to the ground glass setup. 2) Through an "in-between exposure" scheme, where the ground glass is exposed in the time lapse when the shutter is closed. There are also more sophisticated schemes which lie well beyond my expertise. Last edited by Daniel Apollon; February 15th, 2006 at 08:11 AM.

February 15th, 2006, 05:29 AM	#23
Wayne Kinney Major Player Join Date: Jun 2005 Location: Brighton, East Sussex, UK Posts: 938	I have seen the 2nd method working up close, with the light being redirected to the finder between the shutter. Because of this, the finder gives the same 'film motion' live which i thought was clever. __________________ Thanks, Wayne.

February 14th, 2006, 02:49 PM	#18
Dennis Wood Major Player Join Date: Mar 2005 Location: Ontario, Canada Posts: 916	Daniel, any idea what function this has in an Arri camera?

February 14th, 2006, 07:03 PM	#20
Dennis Wood Major Player Join Date: Mar 2005 Location: Ontario, Canada Posts: 916	Let me rephrase that. How is a GG used in a film camera? Same concept as SLR? I would assume somehow the operator is able to look through the lens while shooting, or a seperate finder is used? I've never seen an Arri, or any other film cam for that matter, in person.

February 14th, 2006, 09:43 PM	#21
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Jim. The PCX. Is this a condenser lens with the sides cut off.? Are the Nikon viewfinder condensers separate from their groundglass screens, ie., polished on both sides? A Nikon glass might just fit below the front prism on my gadget or perhaps one each, either side of the groundglass disk. SLR lens >> Nikon condenser-(\| >> groundglass >> \|)-Nikon condenser >> prism pair >> Century Optics 7+ achomatic dioptre >> Camcorder. Do you see this as a solution to edge falloff with widescreen images on the FX1? Is is mainly an issue when I shoot the aerial image with long lenses but is apparent with the groundglass image in certain lighting consitions.

February 15th, 2006, 07:20 AM	#24
Dennis Wood Major Player Join Date: Mar 2005 Location: Ontario, Canada Posts: 916	It's an interesting problem I hadn't thought of. I would have guessed (and then dismissed) the image split solution as a lossy one. As Wayne has alluded, if the shutter is open for 1/48s, then at 24fps you are seeing the same cadence in the viewer as the film is capturing. It must get interesting when frame rates are cranked.