image flip with fiber optic faceplate? at DVinfo.net

Robert Gradisen · June 19th, 2006, 02:10 AM

hi new here, but I have been followng the theads about 35mm adapters for some time , I have made a pretty decent prototype static adapter for my dv cam using a homemade wax screen and a fast minolta lens some pvc pipe and lots of duct tape also a couple of condensers from some old focusing screen (possibly the cheapest and most easily available source for made ti fit plano convex lenses there is) , but having alot of touble trying to figure out how to erect the image ( looked into prisms and mirrors ,porro abbe or double porro seems the easiest or setting up mirrors in such a configuration alternatively a very large and expensive roof-pentaprism and mirror set up)
Anyway i checked out some info on optic fiber face plate ( which have a high resolution and low light loss potential) they come in taper (for image resizing) and inverter styles , I was thinking a combination of which could invert ,enlarge the image and make the adapter more compact , does anyone know anything about this stuff , some of the fiber optics companies claim that these face plates are used for "ccd coupling" also as a cost effective alternative to conventional optics in nightvision equipmet.
I havent found any prices yet so I dont know how feasable this all is but it struck me as a simple solution if you could just stick a couple of these face plates up against your GG say sandwiched inbetween the GG and the PCX

anyway thats my thought
rob

Robert Gradisen · June 19th, 2006, 02:43 AM

some links

http://www.adphotonics.com/products/...faceplate.html

http://www.emagin.com/html/fiber_optic_taper.htm

http://www.fairchildimaging.com/main...fiberoptic.htm

Robert Gradisen · June 19th, 2006, 02:52 AM

better links
http://www.hioptic.com/night-vision-..._faceplate.htm

http://www.incomusa.com/products.html

Robert Gradisen · June 19th, 2006, 02:55 AM

found one for sale

http://www.alibaba.com/catalog/10939...39123&ad84kt=y

Jim Lafferty · June 19th, 2006, 07:46 AM

Just a note -- it needs to be about 43.5mm round to get a full frame image from a 35mm SLR lens.

Bob Hart · June 19th, 2006, 07:47 AM

I investigated coherent fire bundles some time back. These are used to erect "flip" the image from a night vision intensifier for viewing by the eye or a camera. The info I had then was that the resolution was not up to scratch but things could well have changed since.

Robert Gradisen · June 19th, 2006, 09:00 AM

you right looks like the largest at the moment that I can find is about 30mm diameter not big enough but I think some of these places can make to specification and I thought that I saw somewhere somethimg about 70% light transmission I wonder how that stands up against two prisms as far as light loss is concerned though as far as resolution is concerned seems ok for DV anyway I`ll keep looking, still havent got a price on one of these things yet.

rob

Robert Gradisen · June 19th, 2006, 09:11 AM

by the way , a quick question ,if using two prisms do they have to be aluminized on the appropriate sides for refraction or just polished ?
rob

Jim Lafferty · June 19th, 2006, 01:58 PM

70% is terrible. Most flip options utilize front-surface mirrors -- something like three pairs of such mirrors, each suffer something like .5% light loss. When calculated, you're losing something like 5-10% light loss from the flip module, IIRC. 30% is way off the mark, especially when added to other factors (light loss of the 35mm lens, which goes up as DOF and FL goes up; and of course light loss of the diffuser in use).

Bill Porter · June 19th, 2006, 02:19 PM

Actually in real-world applications light loss tends to go down as FL goes up. Fast shorter FL lenses aren't plentiful, so most short lenses lose more light than most long lenses. Even a 20mm F2.0, which sounds like a fast lens if you're fixated on the aperture, only transmits about as much light as a 50mm at F5.0.

Also keep in mind not all lenses are equal... cheap lenses usually aren't as bright as nice (and usually therefore expensive) ones.

Matthew Wauhkonen · June 19th, 2006, 03:23 PM

How much are these? I'd really like to be able to use the viewfinder in my dvx to compose shots rather than the LCD, so even if only for that purpose (inverted in the viewfinder) this might be useful..

Jim Lafferty · June 19th, 2006, 05:07 PM

Quote:

Originally Posted by Bill Porter

Actually in real-world applications light loss tends to go down as FL goes up. Fast shorter FL lenses aren't plentiful, so most short lenses lose more light than most long lenses. Even a 20mm F2.0, which sounds like a fast lens if you're fixated on the aperture, only transmits about as much light as a 50mm at F5.0.

That's all fine and well, but try finding an f/1.4 80-200mm lens around. They don't exist. 50mm on the other hand, they're abundant. That was my point, so as FL of the lens "goes up," so, loosely speaking, does the total minimal lightloss of the system. Most wide to tele lenses with good range between extremes (17-105; 18-80; etc.) I've seen start with a base of f/3.5 or f/4, so your base starts with needing a lot more light suddenly.

Jim Lafferty · June 19th, 2006, 05:10 PM

Also, I was mistaken -- it's a total of four FS mirrors.

Bill Porter · June 20th, 2006, 12:45 AM

Quote:

Originally Posted by Jim Lafferty

That's all fine and well, but try finding an f/1.4 80-200mm lens around. They don't exist. 50mm on the other hand, they're abundant. That was my point, so as FL of the lens "goes up," so, loosely speaking, does the total minimal lightloss of the system. Most wide to tele lenses with good range between extremes (17-105; 18-80; etc.) I've seen start with a base of f/3.5 or f/4, so your base starts with needing a lot more light suddenly.

No, not all f-stops are equal. Just because two lenses are F1.4 for example, doesn't mean they pass the same amount of light. If you use decent lenses, a 50mm F1.4 probably doesn't pass more light than a 200mm F4.0.

Furthermore, a 20mm lens with a given f-stop, for example, won't pass as much light as a 50mm lens with that same max aperture.

Bob Hart · June 20th, 2006, 07:37 AM

Robert.

A reflective coating on the reflecting surfaces would be better but in practical terms is not worth the expense for me because I am still experimenting and sooner or later would injure the reflective coating pulling things apart and reconstructing them.

I'm working at the Fedcourt in Vic Ave Perth tomorrow, probably finishing up at 5pm and also Friday, so could bring the thing in for you to examine if you want to make your way into the city.

I have two built, one set up for a Sony HDR-FX1, the other for a JVC HD100. Most weeks I am in for two or three days a week. Give me an email if you want to set up an inspection time.

June 19th, 2006, 02:10 AM	#1
Robert Gradisen New Boot Join Date: Jun 2006 Location: Amsterdam , Netherlands Posts: 22	image flip with fiber optic faceplate? hi new here, but I have been followng the theads about 35mm adapters for some time , I have made a pretty decent prototype static adapter for my dv cam using a homemade wax screen and a fast minolta lens some pvc pipe and lots of duct tape also a couple of condensers from some old focusing screen (possibly the cheapest and most easily available source for made ti fit plano convex lenses there is) , but having alot of touble trying to figure out how to erect the image ( looked into prisms and mirrors ,porro abbe or double porro seems the easiest or setting up mirrors in such a configuration alternatively a very large and expensive roof-pentaprism and mirror set up) Anyway i checked out some info on optic fiber face plate ( which have a high resolution and low light loss potential) they come in taper (for image resizing) and inverter styles , I was thinking a combination of which could invert ,enlarge the image and make the adapter more compact , does anyone know anything about this stuff , some of the fiber optics companies claim that these face plates are used for "ccd coupling" also as a cost effective alternative to conventional optics in nightvision equipmet. I havent found any prices yet so I dont know how feasable this all is but it struck me as a simple solution if you could just stick a couple of these face plates up against your GG say sandwiched inbetween the GG and the PCX anyway thats my thought rob

June 19th, 2006, 07:46 AM	#5
Jim Lafferty Major Player Join Date: Dec 2003 Location: Brooklyn, NY Posts: 636	Just a note -- it needs to be about 43.5mm round to get a full frame image from a 35mm SLR lens. __________________ Realism, anyway, is never exactly the same as reality, and in the cinema it is of necessity faked. -- J-L G

June 19th, 2006, 01:58 PM	#9
Jim Lafferty Major Player Join Date: Dec 2003 Location: Brooklyn, NY Posts: 636	70% is terrible. Most flip options utilize front-surface mirrors -- something like three pairs of such mirrors, each suffer something like .5% light loss. When calculated, you're losing something like 5-10% light loss from the flip module, IIRC. 30% is way off the mark, especially when added to other factors (light loss of the 35mm lens, which goes up as DOF and FL goes up; and of course light loss of the diffuser in use). __________________ Realism, anyway, is never exactly the same as reality, and in the cinema it is of necessity faked. -- J-L G

June 19th, 2006, 03:23 PM	#11
Matthew Wauhkonen Major Player Join Date: Apr 2005 Posts: 285	Hmm... How much are these? I'd really like to be able to use the viewfinder in my dvx to compose shots rather than the LCD, so even if only for that purpose (inverted in the viewfinder) this might be useful..

June 19th, 2006, 05:10 PM	#13
Jim Lafferty Major Player Join Date: Dec 2003 Location: Brooklyn, NY Posts: 636	Also, I was mistaken -- it's a total of four FS mirrors. __________________ Realism, anyway, is never exactly the same as reality, and in the cinema it is of necessity faked. -- J-L G

June 19th, 2006, 02:43 AM	#2
Robert Gradisen New Boot Join Date: Jun 2006 Location: Amsterdam , Netherlands Posts: 22	some links http://www.adphotonics.com/products/...faceplate.html http://www.emagin.com/html/fiber_optic_taper.htm http://www.fairchildimaging.com/main...fiberoptic.htm

June 19th, 2006, 02:52 AM	#3
Robert Gradisen New Boot Join Date: Jun 2006 Location: Amsterdam , Netherlands Posts: 22	better links http://www.hioptic.com/night-vision-..._faceplate.htm http://www.incomusa.com/products.html

June 19th, 2006, 02:55 AM	#4
Robert Gradisen New Boot Join Date: Jun 2006 Location: Amsterdam , Netherlands Posts: 22	found one for sale http://www.alibaba.com/catalog/10939...39123&ad84kt=y

June 19th, 2006, 07:47 AM	#6
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	I investigated coherent fire bundles some time back. These are used to erect "flip" the image from a night vision intensifier for viewing by the eye or a camera. The info I had then was that the resolution was not up to scratch but things could well have changed since.

June 19th, 2006, 09:00 AM	#7
Robert Gradisen New Boot Join Date: Jun 2006 Location: Amsterdam , Netherlands Posts: 22	you right looks like the largest at the moment that I can find is about 30mm diameter not big enough but I think some of these places can make to specification and I thought that I saw somewhere somethimg about 70% light transmission I wonder how that stands up against two prisms as far as light loss is concerned though as far as resolution is concerned seems ok for DV anyway I`ll keep looking, still havent got a price on one of these things yet. rob

June 19th, 2006, 09:11 AM	#8
Robert Gradisen New Boot Join Date: Jun 2006 Location: Amsterdam , Netherlands Posts: 22	by the way , a quick question ,if using two prisms do they have to be aluminized on the appropriate sides for refraction or just polished ? rob

June 19th, 2006, 02:19 PM	#10
Bill Porter Major Player Join Date: Mar 2005 Location: Ventura, California, USA Posts: 751	Actually in real-world applications light loss tends to go down as FL goes up. Fast shorter FL lenses aren't plentiful, so most short lenses lose more light than most long lenses. Even a 20mm F2.0, which sounds like a fast lens if you're fixated on the aperture, only transmits about as much light as a 50mm at F5.0. Also keep in mind not all lenses are equal... cheap lenses usually aren't as bright as nice (and usually therefore expensive) ones.

June 20th, 2006, 07:37 AM	#15
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Robert. A reflective coating on the reflecting surfaces would be better but in practical terms is not worth the expense for me because I am still experimenting and sooner or later would injure the reflective coating pulling things apart and reconstructing them. I'm working at the Fedcourt in Vic Ave Perth tomorrow, probably finishing up at 5pm and also Friday, so could bring the thing in for you to examine if you want to make your way into the city. I have two built, one set up for a Sony HDR-FX1, the other for a JVC HD100. Most weeks I am in for two or three days a week. Give me an email if you want to set up an inspection time.