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Just got my French Prisms - Page 2

post #31 of 303
Thread Starter 
That's good news Mupi,

Have you tried to set them up like the first image in post 5? I would try that and then angle the rear prism as you go. Good luck.
post #32 of 303
yes I just tried it and I am able to get a nice rectangular image. I am
not playing an anamorphic DVD. I just tried ESPNHD. I just wanted to see
if I can get a nice rectangular 2.35 image. I had to tilt both the prisms
as they werent perfectly normal to the beam. That can be fixed as my
projector is probably tilted. Notthing is perfect yet.

There is some reflection. Mine is table mounted. There is reflection to the
left and back but not like the reflections from the mirror like Massillon Plaque
prisms. If I just keep my hand on the side and back the reflections are gone.
So putting a simple enclosure would get rid of the reflections.

Yes the angles of the 2 prims are the same. It is a good way of cutting the cost
by making the first prism smaller.

I thought the left and right edges were a bit blurry. It could also be the
overscan thing. Who cares about the edges.

I am going to ask my coworker to come to my place so that he can give his
opinion as he has more experience with HT. He can also take a picture.
I am sure he is reading this post :-)

I just wonder why the pro lenses cost $3000. Just due to monopoly.
I think with more and more people going the DIY route the
price of the pro lenses will drop soon.

The picture looks pretty good to me. I am sure it will look a lot better when
I play an anamorphic 2.35 DVD
With a $600 projector and $126 prism I cant ask for more.
My dream of watching a movie without bars seems to be finnaly coming true :-)

will post next week.
post #33 of 303
Quote:
Originally Posted by Mupi View Post

I just wonder why the pro lenses cost $3000. Just due to monopoly.
I think with more and more people going the DIY route the
price of the pro lenses will drop soon.

2 elements verses 5 (or more)...

Mark
post #34 of 303
I was in the last batch and received mine today. For the priced payed for coated lens and 5 dollar shipping to boot I feel this was a good gamble.

I have my 7210 hanging upside down so it's going to be while to test mine (until I can get my box and sled ready).

I have a existing pornamorph 100u (vertical compression). I will build my box around my panamorph's existing sled and bracket. Hope to have pictures someday.
post #35 of 303
Thread Starter 
Good to hear Mupi, glad you were able to get a good image.

jplmain, $5.00 to HI I don't think you'll get that anywhere else.

Guys post them pics when you get them, I'll try to do the same. I'm gonna try to start a wooden enclosure and probably line the top and bottom with something that will grip the prisms. I intend to use some sort of sled or slide system.
post #36 of 303
Quote:
Originally Posted by CAVX View Post

2 elements verses 5 (or more)...

Mark

and what are those extra elements?

MDF or aluminum enclosures? nuts and bolts for adjustment? mounts?

Even if the quality of the prisms is better and there are more
layers of coating it doesnt justify a whopping $3000

They dont have to strive to make such perfect lenses.
How many people here have a projector that is $5000 or more
to justify buying a $3000 lens. Just like there are budget projectors
like IN72 that has an image quality of a $5000 projector, there
could be a budget lens too.

All we need is something like sams prisms that works and that has a
simple enclosure. If someone wants a sled then they have to pay more.
It shouldnt cost more than 50 bucks to make a MDF enclosure.
post #37 of 303
Quote:
Originally Posted by Mupi View Post

and what are those extra elements?

MDF or aluminum enclosures? nuts and bolts for adjustment? mounts?

No, they are extra bits of purpose made glass that correct for focus, CA etc. If anyone says they don't need them, it is because they have not yet seen the improvement they make...

Quote:


Even if the quality of the prisms is better and there are more
layers of coating it doesnt justify a whopping $3000

Allot of the expense comes down to the finish of the surface. Yes the DIY prisms look smooth with no visible surface markings to the naked eye, but under a microscope, they full of pits and grooves. To get the best finish takes time, and time is money...

Quote:


They dont have to strive to make such perfect lenses.

It depends on who is buying I suppose...

Quote:


How many people here have a projector that is $5000 or more
to justify buying a $3000 lens. Just like there are budget projectors
like IN72 that has an image quality of a $5000 projector, there
could be a budget lens too.

All we need is something like sams prisms that works and that has a
simple enclosure. If someone wants a sled then they have to pay more.
It shouldnt cost more than 50 bucks to make a MDF enclosure.

That is subjective...

Mark
post #38 of 303
Well, the volume produced & sold is less which jacks up the per unit price. Photographic lenses have more elements, motors, better housing and I bet are better finished than these prisms but they sell a lot more of them....
post #39 of 303
I guess currently only ball players are buying those $3000 prisms :-)
post #40 of 303
Thread Starter 
I was able to make a simple enclosure with wood & cork board to hold the prism's in place. I aligned the prism's according to the template that I posted above and I was able to quickly test them out. Like Mupi it wasn't perfect but it will work it's just a matter of fine tuning it. The thing is that I have the projector on a shelf over my head and had to hold the enclosure in front of the lens and try to line it up. My image was rectangular though so I am quite pleased.

I snapped some pic's of the enclosure and matierials used, I'll post when I get some time.
post #41 of 303
There's a package waiting at the post office for me! Come on monday!!!!
post #42 of 303
I got mine delivered yday. They are very nicely packed. I hv to build an enclosure and bring down the projector to do some tests.
Oman - any pictures on how you built the enclosure would be useful, thx
post #43 of 303
Can I get the info on where to order these lenses please ? ... send me a pm if necessary
post #44 of 303
Quote:
Originally Posted by Justletmein View Post

Can I get the info on where to order these lenses please ? ... send me a pm if necessary

Sorry it was a one shot deal at (http://www.commandes-groupees.fr/viewtopic.php?p=4384). If you keep a eye on there site you might get chance to order when they get another batch lined up.

Someone on this thread (MUPI) ordered two pairs and might be selling one on ebay.
post #45 of 303
Quote:
Originally Posted by Mupi View Post

I just wonder why the pro lenses cost $3000. Just due to monopoly. I think with more and more people going the DIY route the
price of the pro lenses will drop soon.

The "pro" category is Isco and Schneider. List on the Isco (III) is $5999, List on a Cinedigitar is $4200. So I'm not sure which "pro" lens you are speaking of that is $3k.

But regarding the former, they cost more becasue they are photographic quality lenses, with multiple spherical and cylindrical lens elements. They have adjustable astigmatism correction, and precision (i.e. pro telescope quality) housings. Curves cost more, in many places
post #46 of 303
Hi GetGray,

I think he (Mupi) is referring to the Panamorph UH380 which I already explained (a few posts back) has 5 glass elements not 2...

Mark
post #47 of 303
Thread Starter 
Here go some pics of what I came up with.
LL
LL
LL
post #48 of 303
Thread Starter 
I used the the image on post 5 to get the outside dimensions of the enclosure. If you print it out it you'll notice that it isn't to scale, so like I stated it worked for the outside dimensions. Then I reduced the image on a photocopier to 90% and that brought the image of the prisms closer to scale and that is what I use on the inside of the enclosure to help align the prisms.
LL
LL
LL
post #49 of 303
Thread Starter 
Finally this is how it all came to gether. I'll be recessing the screws, priming and spray painting for a nice finish. Also I'll be making some sort of bracket and mounting it to a drawer slide. A quick test showed it worked nicely, but I need to either mount or bring my projector down to fine tune.
LL
LL
LL
post #50 of 303
Quote:
Originally Posted by CAVX View Post

I think he (Mupi) is referring to the Panamorph UH380 which I already explained (a few posts back) has 5 glass elements not 2...

Oops, sorry. Different conotatations for pro
post #51 of 303
Hi Oman,
Would be helpful to know the outside and inside dimensions and the thickness of the wood/cork board? Does it fit snug?
post #52 of 303
Well done Oman321, Sam would be proud

Mark
post #53 of 303
Thread Starter 
Snowkirk,

The wood is 3/8 X 6 X 36 craft wood. If I did it again I would use 1/2" wood cause you might notice in my last pic one of my side panels split. It's ok I already replaced it, the 36" length left enough scrap.

I got all the material at Lowes. The cork board was a plastic backed disc for plant pots. It cut easily and worked like a charm. The prisms are nice and snug and I have held the enclosure in every direction to test out. The most important dimension is for the side panels, they measure 3 1/8" inches. Originally they measured 3&1/4 and they were sliding everywhere the 1/8th made all the difference. The cork board measures 3/16. The top and bottom pieces are 5&7/8" at the big end and 4&1/4" at the small.

Top and bottom were measured after the fact. The easy way was print out first image in post 5, then reduce to 90%. Cut out both images use bigger one for outside dimensions and smaller one for inside dimensions of cork board. Adhesive to glue cork boards, make sure you account for sides, you might have to trim a little extra from smaller image.


Sam, thanks.

I meant thanks Mark it was early when I posted, although thanks do still go to Sam.
post #54 of 303
So when are we going to see some screen shots?

Mark
post #55 of 303
Thread Starter 
The thing right now is that I have a temporary set up I did for my son's B-day at the beginning of the month, I am trying to figure things out with this. From my current projector location at about 16-17 ft. I am not so sure it's gonna work. It works but the image is taking over my entire 11ft.5in. wall.

I moved my projector to about 12 ft. last night but I haven't been able to test out yet. I'm not sure I want to do this because it would mean that I would have to change a few things i.e. my exhaust vent for the projector, outlet video wires. Also I have been testing regular 16:9 images because I haven't gotten a solution for anamorphic stretch yet. I'm thinking either HTPC or maybe the Key Digital scaler if it's still available when I'm ready.

I will be testing tonight hopefully from my new location and see what I can come up with. I can snap some pics but it wont look right unless I find that my DVD player might do the stretch. It's an upconverting panansonic and it has an extensive menu so im not sure.

For my sanity, and I think you've posted this before Mark. If I start with a 90in. width I would then multiply 90 X 1.33 to get a dimension 119.7?
post #56 of 303
Quote:
Originally Posted by oman321 View Post

Also I have been testing regular 16:9 images because I haven't gotten a solution for anamorphic stretch yet. I'm thinking either HTPC or maybe the Key Digital scaler if it's still available when I'm ready.

What source material are you running? Whilst HD might pose problem for some projectors, SD DVD (set to 16:9) should be able to be scaled using either "letterbox" or "4 x 3 zoom" in pretty much every projector except the Benq - w100 (which for reasons I can't work out does not have a letterbox mode)...

Quote:


I will be testing tonight hopefully from my new location and see what I can come up with. I can snap some pics but it wont look right unless I find that my DVD player might do the stretch. It's an upconverting panansonic and it has an extensive menu so im not sure.

For the purpose of testing and initial set up, set it back to SD. The fact that you'll be using the full panel will be a huge PQ improvement anyway...

Quote:


For my sanity, and I think you've posted this before Mark. If I start with a 90in. width I would then multiply 90 X 1.33 to get a dimension 119.7?

Your math looks good to me. Once the prisms are aligned correctly (and you need a 2.37:1 AR screen to do this), you will have a 1.33x stretch optical adaptor...

Mark
post #57 of 303
Thread Starter 
I was viewing 16:9 HD and SD. TNT was showing Forrest Gump and we have both versions of the station on Comcast Cable. With my cable box set to 480P on SD channels it creates a 16:9 image. instead of 4:3 when set to 480i.

I have an Epson HC 400 which offers some good aspect control but not vertical stretch. It was interesting because if offers a through mode for 16:9 HD & SD which reduces the image by about 10% overall but does not cutoff anything that I noticed. This might be a solution I could utilize perhaps if it comes down to it.

I quickly looked at the manual on line it states "Use Wide if you want to expand a 4:3 image to 16:9 so it fills the whole screen" so I suppose this is the mode I want on this projector.
post #58 of 303
Quote:
Originally Posted by oman321 View Post

I was viewing 16:9 HD and SD. TNT was showing Forrest Gump and we have both versions of the station on Comcast Cable. With my cable box set to 480P on SD channels it creates a 16:9 image. instead of 4:3 when set to 480i.

Sounds like it is looking to 16:9 for any HD input (not good, but nothing you can so - mine also does this), so set to 480i and see what happens...

Quote:


I have an Epson HC 400 which offers some good aspect control but not vertical stretch. It was interesting because if offers a through mode for 16:9 HD & SD which reduces the image by about 10% overall but does not cutoff anything that I noticed. This might be a solution I could utilize perhaps if it comes down to it.

No projector (even the Cinewide from Runco) lists it as vertical stretch...

Quote:


I quickly looked at the manual on line it states "Use Wide if you want to expand a 4:3 image to 16:9 so it fills the whole screen" so I suppose this is the mode I want on this projector.

So long as it clips the top and bottom off the image and does not stretch it...

Mark
post #59 of 303
Thread Starter 
Actually it states that it stretches left and right but leaves the center unchanged.

There is a note at the bottom of all the aspects that states " if you display a 4:3 image using the Zoom setting, the top and bottom will be cutoff" perhaps this setting then?

Here's a link to the page with the manual if you have the time and energy to take a peek it would be appreciated. It lists the aspects on page 27.

http://www.epson.com/cgi-bin/Store/s...odoid=63059180

I knew it wouldn't list it as V. stretch, I had previously asked and I was told the Epson's didn't offer it. Tough to get your head around all of this it took a while to understand CIH and as you can see I still have questions. Thanks again for the help.

Quick correction the cable box goes to 4:3 on SD when SD override is set to off. I will do that to see.
post #60 of 303
Oman,
Thanks for your response. Got the idea, trip to Lowes or HD this wkend.
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