DIY anamorphic lens

[rwhitley]

Hi Nox,

be careful, if you used a two part epoxy for the water prisms it will leak on you in a few weeks. I know it sounds odd but trust me on this one. You need to use silicone for the water prism.

Rick

[Nox]

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.

[JudeBarnes]

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?

[tonypeps]

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

[JudeBarnes]

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.

[PTremb]

has anyone tried to make a much larger verson for use on crt projectors? if so how did you fare.can this be made to a demension of say 24" long by 7" high.i would love to use more of my display feild to prevent having to replace $700ea tubes with only 50% used area.

[JudeBarnes]

I think mine is larger than any of the posted plans. It should work at any size, as long as the angles are correct (shouldn't it?) This is a good question-- I suppose at a certain size, there would be so much liquid area to pass through that the image might start to suffer.

[Michael F T]

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.

[JudeBarnes]

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!

[Jonathan M]

Instead of compressing the vertical, I believe that Michael may be expanding the horizontal, thus getting an even larger picture.

I'm sure Michael will correct me if I'm wrong!