DIY anamorphic lens

[mhelin]

Originally posted by solarscreen
I also noticed on the website for Lambda Research Optics that they arrange their anamorphic prism pairs differently than what has been shown in this thread. Take a look at this page where the prism arrangement and the light path are shown in a drawing:

www.lambda.cc/PAGE131.htm

Is this different than what you are attempting to do here?

Not sure, but he first glass is in Brewter's angle which means it's reflects a lot of light and polarizes it (see http://en.wikipedia.org/wiki/Brewster's_angle). Also the entry glass is not coated from that surface - only the exit surfaces are coated. Not useful for us I think as the light intensity will also be lowered - we are not building sun classes here

[ROTTEN ROD]

Well Xmas and the such is over. I have spent a lot of time working through the blu-ray/hd dvd problem and have finished my second case for the lens setup. Here's what I have thus far:

Panasonic pt-ae2000u (GREAT PURCHASE, SUGGEST IT DURANGO)
Carada 120" (2:35) screen
Onkyo 875 receiver
Samsung bd-up 5000

http://picasaweb.google.com/spurrell.jennifer

(Sorry for all the pictures, but I have been using this file to send friends.)

A lot of tweaking done and lots to be done. I have the projector running about 12' from the screen and it is ceiling mounted. As I said this is my second case and I think I will do one more using heavier wood and will line it with velvet.

So far, I have managed to tweak the lens to get it very close to the full 120" but I have some overlap, the framing does a great job in hiding this fact, but I know its there and will hope to fix with next case. I have one rainbow, about 24" over on the right top of screen, again tweaking. The drawer hinges on the ceiling work great, and when I have the case in front of the PJ it has a slight click to let me know it is locked in place.

I love the Panny, and the Onkyo and the screen. I am still working through the Samsung Dual player, but if you check AVS it is a hot topic right now.

I have to thank Mark and Roar for the lenses, help and info. Mark your grid from your website allowed me to properly line up my lenses quick and easily.

I have a friend who is an optometrist, he is checking on maybe getting my lenses coated in anti reflective... I hope this pans out as well.

See attached link to my new HT room. Some pics at the end showing before and after i have stretched the picture. LOTR is SD dvd and Casino Royal is 1080i through my PVR...

Thanks to all on this thread, without it I would have bought a 50" lcd and stuck it on the wall!!! Tough to awe your friends with that...

ROTTEN...

[riskpeep]

I'm writing to ask why no-one has really looked into using eyeglass lens blanks as a way to get an anamorphic lens put together.

I've been reading this thread and all the others I could find to figure out how to DIY an anamorphic lens. And while I like the idea of using prisms, it seems that the challenges this approach brings (big heavy prisms, difficulty finding a way to get them coated, thick glass which accentuates CA) force us down into a land a sub-optimal solution.

I've been looking around and it seems that if we could get a lens blank with 0.00 spherical correction, and the right amount of cylindrical correction (based on my math, somewhere between +1.25 and +1.5), that we'd have a really cheap solution for an anamorphic lens.

I understand that we use big prisms today to account for the fast light coming out of a short throw projector, but THAT problem is really caused by the size of the prisms. With the right lens, we could put the element right up near the projector output and do everything we need and still fit within the smaller bounds of the lens blank.

Not to mention that for eyeglasses, the lenses are comparatively cheap, can be had with just about any coating we might want as part of the package, and come in a whole variety of diffraction indices which would let us pair up elements to correct CA if we need to.

What am I missing here? Are there any opthomologists out there who might be able to discuss the feasibility of this idea

[Mark Techer]

Hey Rod,

That set up looks really good. Get those photos over to Alan at AVS for the official 235 thread please.

Riskpeep,

I think that you would find that cylindrical elements are not that cheap for quality parts or readily available in decent (at least 100mm) sizes.

I would love to explore the possibilities, but could not even find a plano-concave element to match the plano convex element I bought.

Besides the parts, there is the alignement issues, and why prisms have been favourable for DIY - they are more forgiving to alignemtn errors...

Mark

[durango9898]

Originally posted by ROTTEN ROD


Panasonic pt-ae2000u (GREAT PURCHASE, SUGGEST IT DURANGO)
Carada 120" (2:35) screen
Onkyo 875 receiver
Samsung bd-up 5000

Rotten,

Beautiful setup. Great to hear that it is working out well. I also got the Panasonic (had to get it before Dec 31st) so went ahead and purchased it. In the process of hanging it. Did my own screen (with laminate - 109" (2.37) wide). Also, completed the case for the prisms and in the process of painting etc. Should be finishing it in the next couple of weeks. Will post pictures once done.

Thanks,
kyess

[Mark Techer]

So we beat prisms to death, does anyone want to discuss cylindrical elements?

Mark

[ROTTEN ROD]

I have had a quick look at the Cinemascope site, they look pretty neat and compact. I have brought it up with my Optometrist friend and he is looking into it. He did state that it would make the anti reflective coating procedure much simpler.

He states that the big problem with getting these things coated is not the procedure but the shape. Easy enough to put a Eyeglass lens through a machine that coats Eyeglasses all the time, but try and mount one of these Lenses to the $$$$ pricey machine and nobody is eager...

I have send my buddy some stuff and I am hoping he takes the time to review and we give it a go. Although it might lead to Divorce on my end after just going throught the motions on my last HT setup...

Rotten...

[Agus Widarto]

Hai all... this picture is just for refresher and intermezzo talk about anamorphic lenz.

regards

[Agus Widarto]

And here the other one....


regards

agus

[durango9898]

Originally posted by Agus Widarto
And here the other one....


regards

agus

Agus,

The lens looks like an ISCO. Is that correct or is it a DIY lens.

kyess