Would a diy anamorphic lens work on a 4:3 projector?

[yoda313]

I have a question about anamorphic lenses. I have an old eiki lc330 projector that is a 4:3 lcd projector. It works ok but is 4:3 and less than dvd resolution. I was looking at anamorphic lenses on ebay and they start at 50.00 usd and up. Also I don't know if any would be compatible with my projector.

I want to make my projector less square and fill up the screen properly (ok i'm back to using just a bed sheet but it is my screen for now).

Would this technique work on a 4:3 projector or is it only valid on a projector that already does 16:9 natively?

The article I'm referencing is this:

http://www.zuggsoft.com/theater/prism.htm

Has anyone done something like this? I'm interested in any ideas about this. Thanks.

Fyi I'm not interested in buying a new projector right now. I just want to watch widescreen dvds without the large black bars on 2.35:1 movies. I did do a test with 16:9 on my ps3 over composite cables and the people were tall and skinny as expected (but the screen was large enough that its not really that distorted - about 60" or so give or take).

[yoda313]

Bump

Any ideas on this? Would a do it yourself anamorphic lens work on a 4:3 projector? Or is this only tailored to a projector that has 16:9 output?

I'd hate to waste money on something that wouldn't even work.

Thanks.

[filmboss80]

I have serious doubts. I'm convinced that the method described in the link will only introduce image distortions and edge color separations, especially around the outer perimeter of the frame.

Save your time and money. Learn to live with the black bars.

[jagabo]

If it works in movie theaters why wouldn't it work with a home projector? It should be good for a 4:3 to 16:9 stretch.

[yoda313]

@filmboss80 - I do understand it wouldn't be perfect. But keep in my mind my projector is vga resolution and isn't super sharp to begin with (but very good just not cutting edge high def). And I know any lens wouldn't make it high def I'd just want a larger video image when its a widescreen image rather than being smaller in frame being letterboxed up on the 4:3 image. I do normally do ok with blackbars but if there is a project that is relatively affordable and unique I'd be interested in experimenting.

@jagabo - thanks for the opinion. I may try it if I can get a hold of some inexpensive prisms. Anyone have ideas where I might get some? What about a place like bed bath and beyond? Or a hardware store like home depot?

I'm looking to try with some small 2 or 3 inch ones just to see how it would work at all on my setup. I don't even know where to look. I want to try small before I even think about special ordering online.

[filmboss80]

If it works in movie theaters why wouldn't it work with a home projector? It should be good for a 4:3 to 16:9 stretch.

It does work with anamorphic lenses that have been ground to specification by a good optics company. (I use anamorphic lenses in a variety of applications.) Movie theaters don't use prism boxes; they use specially-made projector lenses. The DIY method described in the OP's link is interesting, but I am not convinced that the chromatic aberration issue can be satisfactorily solved using prisms.

But hey, if it doesn't cost much, give it a try. Be sure and report your findings. My opinion on this subject can easily be changed if the results prove to be productive.

[yoda313]

Be sure and report your findings. My opinion on this subject can easily be changed if the results prove to be productive.

Sure thing. First thing is to get some prisms. I don't know if I'll start today or not. Like I said I want to start cheap with something that seems unproven at least to this forum.

[filmboss80]

When dealing with lenses (or prisms, I assume), you cannot simply go cheap, as you will get distortion errors. Try looking around your environment through a drinking glass; you'll see how warped and wobbly moving things get. This is why I've had my original doubts about about that DIY plan. I noticed that their "Star Wars" demonstration appears to be a simulation using direct freeze frames from the movie--not snapshots of the actual projected image.

You can look for prisms at http://www.edmundoptics.com/onlinecatalog/browse.cfm?categoryid=38.

[jagabo]

I noticed that their "Star Wars" demonstration appears to be a simulation using direct freeze frames from the movie--not snapshots of the actual projected image.

In the text he says that the last shot was a photo of the projected image. He also talks about how it's not as good as a proper cylindrical stretch as you would get in a real theater. In the sample image the chromatic aberration and linearity problems don't look too bad until you get pretty close to the edge of the screen.

How much do true anamorphic lenses for projectors cost?

[vhelp]

actually, those pics in the original post link look real. if you look at the edges by dragging left/right the scrollbar, you can see some warpness in the black area that meets the picture.

also, the author in that link mentioned that the distortion was caused by his digital carera and not the proj or lens. see near bottom of that page.

even if there are some distortion, i mean, how many of you all been to a movie theater and watched their distorted (burry) walls? i've never seen a clean and sharp movie in any theater in all my life. i think that the (especially) the last pic in that link, it is a true represensation of the quality level to expect from this--course, bare user experience and tools in that author's project, ymmv.

so, sitting down and watching a movie under those conditions shouldn't be any worse than going to an actual theater and see similar problems--after a few minutes sitting, everything would become asthetic by them.

this looks like it could work. what is the actual size of your viewing screen, yoda?

keep looking on ebay and maybe amazon. don't bid until the last minute. these guys all know what they are doing and if you bid early in the week or window of their time frame they jump in and bid over you, making you hunger for another bid. i dont know what the term for that nonsense is, but its evil how these people conduct business on ebay. anyway. keep shoping around for the things you need, if you're still interested that is. if you've got time on your hands and price is right, then go for it. good luck, and let us know how you make out.

-vhelp 5466

[yoda313]

what is the actual size of your viewing screen, yoda?

Well it varies depending on how far away the table is from the cabinet I use to drape the sheet. Generally speaking about 60" square. Give or take.

I guess I won't be getting to this today. But I'll try to look for some in the near future. I'll post whatever results I can get.