Yeah...I know. But I was in a rush to get these first prisms done.
I actually bought Silicon to use, but reading the directions, it would have been 5 minutes to cure, 24 hours to harden, and an additional 24 hours to assure it's dry enough to have no leaks. It added up to 2 days worth of waiting just to fill it with water. THEN, I'd have to glue the hole cap on which would take another two days to dry completely.
Ugh! I just wanted to see if the prisms would work, so I used the epoxy.
On the good water prism, I will use the Silicon.
I actually bought Silicon to use, but reading the directions, it would have been 5 minutes to cure, 24 hours to harden, and an additional 24 hours to assure it's dry enough to have no leaks. It added up to 2 days worth of waiting just to fill it with water. THEN, I'd have to glue the hole cap on which would take another two days to dry completely.
Ugh! I just wanted to see if the prisms would work, so I used the epoxy.
On the good water prism, I will use the Silicon.
DECinema: Thanks for posting those links, especially the thread. I haven't looked in depth into them yet but hopefully there's some info in there on 2.35 ?
Nox: Great idea on the box, I'm picturing a fairly thin piece of plastic there-- when you sawed it, how did you take care not to crack or split it? It sounds like yours is fairly small, and that's great if it works with yoru projector, to keep the lense assembly as small as possible. I think I need 5" minimum for my projector, and I think 6" or 7" for the front prism may be better if I intend to tilt them at sufficient angles for 2.35. As far as I know the fence tubing comes only in 5" or 6" max. Can anyone think of any other pre-made acryllic/plastic objects taht exist out there in hardware stores or craft stores that one use? The fencing is nice because it's wide, has thick edges to bond to, and easy to cut.
Museum glass: has anyone out there actualyl compared window glass to anything "better"? Anyone have a good source yet for any other kind of glass than window/frame glass that is somewhat economical?
Nox: Great idea on the box, I'm picturing a fairly thin piece of plastic there-- when you sawed it, how did you take care not to crack or split it? It sounds like yours is fairly small, and that's great if it works with yoru projector, to keep the lense assembly as small as possible. I think I need 5" minimum for my projector, and I think 6" or 7" for the front prism may be better if I intend to tilt them at sufficient angles for 2.35. As far as I know the fence tubing comes only in 5" or 6" max. Can anyone think of any other pre-made acryllic/plastic objects taht exist out there in hardware stores or craft stores that one use? The fencing is nice because it's wide, has thick edges to bond to, and easy to cut.
Museum glass: has anyone out there actualyl compared window glass to anything "better"? Anyone have a good source yet for any other kind of glass than window/frame glass that is somewhat economical?
Getting Started
Ok, so I was at Menard's (a hardware store) today buying Christmas presents, and they had a special sale. 16% off anything you could fit into a brown paper grocery store size bag. So I decided to pick up a few of the things we've spoken about here, a protractor, some Silicone sealant, a few cheap picture frames, glass cutter etc, all 16% off. So I plan on starting this project soon after the holidays are over, and documenting it on the web like Tor has done. Hopefully, someone will find my experience as useful as I've found everyone else's.
The true meaning of this post is to bump this thread and to wish everyone a Merry Christmas, and a Happy New Year!
Tony
Ok, so I was at Menard's (a hardware store) today buying Christmas presents, and they had a special sale. 16% off anything you could fit into a brown paper grocery store size bag. So I decided to pick up a few of the things we've spoken about here, a protractor, some Silicone sealant, a few cheap picture frames, glass cutter etc, all 16% off. So I plan on starting this project soon after the holidays are over, and documenting it on the web like Tor has done. Hopefully, someone will find my experience as useful as I've found everyone else's.
The true meaning of this post is to bump this thread and to wish everyone a Merry Christmas, and a Happy New Year!
Tony
Tony! Good luck and be sure to post your results here, or any questions you have along the way!
I still haven't mounted my two prisms into a housing. Every time we watch a movie I setup the two prisms in place in front of the projector, I've got it down now so quickly that I can get it setup in a matter of 30 seconds or so, with the help of some putty to keep the front prism in place. (The smaller prism I just lean up against the projector). Still haven't had time to work on the "tubing" design. Does anyone know of any materials out there in square tubes larger than 5 or 6" ? The fence post idea is great but for a larger front prism I think I need something larger than what is manufactured for the vinyl fences.
I still haven't mounted my two prisms into a housing. Every time we watch a movie I setup the two prisms in place in front of the projector, I've got it down now so quickly that I can get it setup in a matter of 30 seconds or so, with the help of some putty to keep the front prism in place. (The smaller prism I just lean up against the projector). Still haven't had time to work on the "tubing" design. Does anyone know of any materials out there in square tubes larger than 5 or 6" ? The fence post idea is great but for a larger front prism I think I need something larger than what is manufactured for the vinyl fences.
I did it!!
Ok, so after months of stalling and searching alternatives, I finally made an anamorphic lens.
I didn't want a compression lens, I wanted to expand the picture.
I am having my kitchen done and my friend/contractor helped me out by cutting a few wedges from a piece of fence post I bought at Home Depot. He used a miter and cut them in 2 mins.
I still wasn't sure it would work, so I used some thin sheets of plexi glass and glued them to the wedges with water proof silicone.
Here is the key to not getting leaks (I think). I didn't close the 1/4 inch hole I made to fill the prisms. And since I wanted an expansion lens the prisms will be on their sides not putting up and down (it won't spill out). It worked!! Now it is a temp setup currently, but now I understand the tube in a picture of the prisms in the original website for making these . The liguid when sealed is cold or room temp. The lens then is in front of the projector and expands. Then contracts...then expands. If the prism has an opening to release the pressure and not super full, the silicone isn't forced to expand and contract and then create holes.
I now have the confidence to make a nicer perm product with glass. The other nice thing is that I can expand beyond 1.85 and create a 2.35 picture if I get a scaler.
Ok, so after months of stalling and searching alternatives, I finally made an anamorphic lens.
I didn't want a compression lens, I wanted to expand the picture.
I am having my kitchen done and my friend/contractor helped me out by cutting a few wedges from a piece of fence post I bought at Home Depot. He used a miter and cut them in 2 mins.
I still wasn't sure it would work, so I used some thin sheets of plexi glass and glued them to the wedges with water proof silicone.
Here is the key to not getting leaks (I think). I didn't close the 1/4 inch hole I made to fill the prisms. And since I wanted an expansion lens the prisms will be on their sides not putting up and down (it won't spill out). It worked!! Now it is a temp setup currently, but now I understand the tube in a picture of the prisms in the original website for making these . The liguid when sealed is cold or room temp. The lens then is in front of the projector and expands. Then contracts...then expands. If the prism has an opening to release the pressure and not super full, the silicone isn't forced to expand and contract and then create holes.
I now have the confidence to make a nicer perm product with glass. The other nice thing is that I can expand beyond 1.85 and create a 2.35 picture if I get a scaler.
Micheal can you describe more about what you're doing-- why is it that you expand instead of compress? What kidn of projector setup, etc? Typically, obviously, we setup these lenses in front of a projector which is projecting an image at a full 4:3 panel, wishing to squeeze it into it's proper ratio. I'm really curious why you're expanding?? Thx in advance, tell us more!
I see so you send the projector full panel and then expand it to it's proper ratio, rahter than compress. I can see why this would be preferable in some isntances, for example, if the projector were much closer to the screen, and need to expand the picture larger ! But, I'm curious what you do to your source image exactly to get it squeezed without losing pixles? Do you turn the projector on it's side???
This is what I think would give a great picture...
Anamorphic PAL DVD material is 720x576 in resolution.
I think that an 800x600 panel, cropped to 720x576 would thus produce the exact pixels as are present on the DVD.
Now, project that image through an anamorphic lens (One for 16:9, and one for 21:9 etc.) and you have a superb image. You can choose whether to compress vertically or expand horizontally as needed. No rescaling digitally taking place. Just optics. You also only need an 800x600 sized screen.
Now, I am assuming that 2.35:1 DVDs are recorded anamorphically, so that the image takes up all the available vertical pixels. If this is incorrect, then at least it would work for 1.85:1 images.
Obviously if you want to view a higher res image it'll start degrading quality, but for DVD's, I can't think of anything better.
Just a thought
Anamorphic PAL DVD material is 720x576 in resolution.
I think that an 800x600 panel, cropped to 720x576 would thus produce the exact pixels as are present on the DVD.
Now, project that image through an anamorphic lens (One for 16:9, and one for 21:9 etc.) and you have a superb image. You can choose whether to compress vertically or expand horizontally as needed. No rescaling digitally taking place. Just optics. You also only need an 800x600 sized screen.
Now, I am assuming that 2.35:1 DVDs are recorded anamorphically, so that the image takes up all the available vertical pixels. If this is incorrect, then at least it would work for 1.85:1 images.
Obviously if you want to view a higher res image it'll start degrading quality, but for DVD's, I can't think of anything better.
Just a thought
Almost all DVD movies have anamorphic encoding on them. Some movies are 1.85:1, and some are 2.35:1. Movies that are 2.35:1 are actually filmed w/ an anamorphic lens to fit on 35mm film frames (which normally has a 1.85:1 aspect ratio). Then when projected, the theatre's projector will switch to an anamorphic lens to reverse the effect, thus making it wider. That's why 2.35:1 movies are refered to as "anamorphic widescreen".
As far a DVD's go, anamorphic has a different meaning. Both 1.85:1 and 2.35:1 movies are anamorphicly encoded on most DVDs so that it will fit on a 16:9 (about 1.78:1). Usually, 1.85:1 movies have the sides croped just a slight amount, while 2.35:1 movies have black bars on the top and bottom (although they're of course not as big as they would be on a letterbox 3:4 picture).
As far a DVD's go, anamorphic has a different meaning. Both 1.85:1 and 2.35:1 movies are anamorphicly encoded on most DVDs so that it will fit on a 16:9 (about 1.78:1). Usually, 1.85:1 movies have the sides croped just a slight amount, while 2.35:1 movies have black bars on the top and bottom (although they're of course not as big as they would be on a letterbox 3:4 picture).
Expansion
I like a bigger image and that's why I expand.
The way I did it is just turn the prisms on their side. Instead of the point of the prisms putting vertically, they point to horizontally.
It's literally turning the whole lens on it's side.
I had a problem with air bubbles but since I didn't seal it up, I used a copper wire to pop them all.
I also used Walgreens Mineral Oil and it looks great.
Currently, I am using Plexi-glass and lose some of the brightness gains, but I still like it more since I don't have the black bars.
BTW - to view a 2.35 movie with all of the pixels you need a scaler to zoom in on only the picture because the 2.35 DVDs have the black bars encoded on the dvd.
I like a bigger image and that's why I expand.
The way I did it is just turn the prisms on their side. Instead of the point of the prisms putting vertically, they point to horizontally.
It's literally turning the whole lens on it's side.
I had a problem with air bubbles but since I didn't seal it up, I used a copper wire to pop them all.
I also used Walgreens Mineral Oil and it looks great.
Currently, I am using Plexi-glass and lose some of the brightness gains, but I still like it more since I don't have the black bars.
BTW - to view a 2.35 movie with all of the pixels you need a scaler to zoom in on only the picture because the 2.35 DVDs have the black bars encoded on the dvd.
Even though you say you lose some brightness overall I think you are gaining some brightness, too, by losing the black bars and filling it with pixels instead.
I definitely CANNOT make my image bigger. If I do I will see the artifacts already inherent even more. The compression of the image has eliminated the two most pesky problems for HT viewing for my wife and I:
1. The black (grey) bars/lightspill
2. The horizontal scanline artifacts which occur on most LCDs with rapid vertically moving objects.
I definitely CANNOT make my image bigger. If I do I will see the artifacts already inherent even more. The compression of the image has eliminated the two most pesky problems for HT viewing for my wife and I:
1. The black (grey) bars/lightspill
2. The horizontal scanline artifacts which occur on most LCDs with rapid vertically moving objects.
Glass?
Where does everyone get your glass? Will Home Depot glass work? It seems to be a bit reflective but what do I know. HD had some 4" square tubing and I made perfect cuts with my mitre saw so the main part of the prism is all set. I have some of the glass and was about to glue it but I want this to be my last one so I don't want to mess it up. Is HD glass ok or should I look at something else?
Thanks,
Craig Carrigan
Where does everyone get your glass? Will Home Depot glass work? It seems to be a bit reflective but what do I know. HD had some 4" square tubing and I made perfect cuts with my mitre saw so the main part of the prism is all set. I have some of the glass and was about to glue it but I want this to be my last one so I don't want to mess it up. Is HD glass ok or should I look at something else?
Thanks,
Craig Carrigan
Craig,
If you're ready for the final revision, check out www.framingsupply.com. It looks like the way to go for pre-cut, non-reflexive glass for a decent price. However, if you're like me, then your first attempt at gluing the glass pieces to the frame is going to result in a lot of smearing, smudging and leaks. So I'm using the cheapest picture frame glass I can find so I can practice my gluing technique.
Lifter,
Up until a few posts ago, we've been talking about lenses that compress the image vertically. But it looks like Michael F T has made one that expands it.
If you're ready for the final revision, check out www.framingsupply.com. It looks like the way to go for pre-cut, non-reflexive glass for a decent price. However, if you're like me, then your first attempt at gluing the glass pieces to the frame is going to result in a lot of smearing, smudging and leaks. So I'm using the cheapest picture frame glass I can find so I can practice my gluing technique.
Lifter,
Up until a few posts ago, we've been talking about lenses that compress the image vertically. But it looks like Michael F T has made one that expands it.
I believe a couple posts back said not to use the framing supply place as the glass would blur the image, it was only meant for up close viewing. I have been practicing (two models down already) and want to do a final version now. The 4" square piping from HD really did the trick. You just have to have a 12" or greater mitre saw to go all the way through (my 10" wouldn't make it).
Craig
Craig
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.