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Alan, The CI does do a "double stretch"  

post #1 of 18
8/23/00 at 5:32am
Thread Starter 
Hello, Alan.

I spoke with you on the phone a couple of weeks ago right before I purchased my CI from you and asked if the CI had the ability to do a "double stretch" for future 2.35:1 lenses. You said it could not, and while that is true to some degree (becuse it does not actually stretch twice) you can still fill an entire 4:3 screen with a 2.35:1 ANAMORPHIC dvd without any cropping. The dvd MUST BE ANAMORPHIC. The CI needs to be set to 16:9 mode then Widescreen on the anamorphic selection. This will result in a super stretch that fills the whole panel for possible 2.35:1 lenses. I am letting you know because it could be a good selling point in the future. I know I really wanted it to have the ability to do this. Now if we can just talk cygnus into making that extra lense for the Panamorph...

One quick question: My 16:9 dvd's are playing with a very slight bend at the top of the screen when playeed through the CI. What causes this and can it be eliminated?

Jeff

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post #2 of 18
8/23/00 at 5:53am
Jeff
This is a zoom mode. You are loosing side picture information. The Slight band you are seeing I take it is a black band. Your projector should have a horizontal and vertical position control!
Good luck!

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Thanks Very Much!

Alan Gouger
AV Science
www.avscience.com
post #3 of 18
8/23/00 at 7:28am
Thread Starter 
Thanks for the info. about the H/V position control. I'll check that out when I get home tonight. I am about 80% sure you might be wrong about what I described being a zoom mode. I spent alot of time last night going back and forth between aspect ratios and paying VERY close attention to to loss of picture information on the sides. There was none. I'm almost positive. I also know the image was already stretched in ANAMORPHIC MODE, (projector in 4:3 mode, like playing a anamorphic dvd without squeezing it) then when I made the switch, it was REALLY stretched. I will double check this because you seem to disagree, but I did check it several times last night for loss of picture information, or cropping like a zoom would do, and it did not do this.

Jeff
post #4 of 18
8/23/00 at 8:10am
Alan,

I have to admit that Jeff is correct on this one. With my CI setup at 800x600 and the screen format set to 16x9, I can put the CI into Widescreen mode which only stretches the image vertically (no side cropping). I even did a test with AVIA to prove this. Then I can squeeze the image back down with projector's vertical amplitude control for CRT projectors or it can be done optically with an anamorphic lens on digital projectors as Jeff described. Again, this only works with 2.35:1 Anamorphic DVDs!!

Also, I think Jeff mentioned a slight vertical "bend", not "band" at the top of the screen. I see this also on my screen as well. It is probably the top 5% of the screen that bends to the right.

------------------
DMan
The Academy Home Theater

[This message has been edited by DMan (edited 08-23-2000).]
post #5 of 18
8/23/00 at 10:39am
This is very interesting. I had no idea this did this. The intent was to blow up 235:1 without geomitry distorion to eliminate black bars. Maybe by choosing the aspect ratio in the setup menue it changes this.
This is good news for those who want to use a 235 lens like myself.
As far as the bending issue it sounds like a macro vision problem.
I will have to try this as I have a sony 7000 that I can turn off the macro vision.
I wont have time for a day or two but I am going to give this a follow up.
Thanks for clarifing this!
This is great.

------------------
Thanks Very Much!

Alan Gouger
AV Science
www.avscience.com
post #6 of 18
8/23/00 at 12:01pm
Alan,

Thanks for looking into the bending problem, you may in fact be correct with regards to it being a Macrovision problem, but it will be interesting to find out for sure.

For those folks that have emailed me to dicuss what this function on the CI will do, a picture is always worth a thousand words. Many people have already done this on the HTPC side of things with regards to using Jim Ferguson's YXY software. Essentially you are taking a 2.35:1 DVD and stretching it vertically to fill a 4:3 area with the active 2.35 image area. Then you may either use a 2.35:1 anamorphic lens for single lens projectors, or you can reduce the vertical picture on a CRT unit. These illustrations below should help:

2.35:1 Anamorphic DVD shown on 16:9 screen(correct aspect ratio)

http://www.mindspring.com/~daalcorn/CI1.jpg


2.35:1 Anamorphic DVD shown on 4:3 frame(actual anamorpic DVD image)

http://www.mindspring.com/~daalcorn/CI2.jpg


2.35:1 Anamorphic DVD shown vertically stretched(image area is stretched to fill 4:3 frame)

http://www.mindspring.com/~daalcorn/CI3.jpg




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DMan
The Academy Home Theater
post #7 of 18
8/23/00 at 9:31pm
Thread Starter 
Yes, it is about the top 5% that bends to the right on mine as well.

Jeff
post #8 of 18
8/26/00 at 4:26pm
I don't like what I am reading in regards the negative effects of the Macrovision copy guard may be playing with our software/hardware combinations, regardless of what dislay devices are been used.
Macrovision boasted that no ill side effects would occur as a consequence of their stupid designs, but it seems that what some of us that were considering being a sync problems with the CI and projectors may in fact be precisely a problems derived from the copy guard signals! Argh!

The discussion about the use of the CI and lenses is quite intriguing. I am going to try it since I got both the CI and Isco anomorphic lens...

-THTS
post #9 of 18
8/26/00 at 7:05pm
Frank
Let us know what you think while using the 235 lens. You will find with the dila zoomed as small as possible you will still loose the corners in the lens. Still gives you the potential of the picture quality.


------------------
Thanks Very Much!

Alan Gouger
AV Science
www.avscience.com
post #10 of 18
8/26/00 at 7:42pm
There's a misconception that keeps coming up every time people start talking about using a Cinemascope lens to project a 2.35:1 image from a 4x3 projector.

These lenses expand the image horizontally by a factor of 2. You DO NOT want to stretch the source to simply fill the entire 4x3 panel. Doing that will result in a projected image that is 2.66:1 (8x3) and geometrically distorted.

Instead, if you want the proper results, you should create a windowboxed image that is 1.175:1, leaving about 6% of the panel black on each side.
post #11 of 18
8/27/00 at 7:55am
Mark
You are correct. I think most including myself are speaking in general terms and realize this but this could be misleading to anyone reading this for the first time.
One can also fill the sides and expand the height to compensate but they would loose some vertical picture info.

------------------
Thanks Very Much!

Alan Gouger
AV Science
www.avscience.com
post #12 of 18
8/28/00 at 3:48am
Thread Starter 
Concerning the "bending" at the top of the screen: I was just reading the CI manual and noticed that it says if the FRAME SYNC is either on or off, depending on your projector, the image may bend at the top. Switching from one to the other could be the key. I have not had a chance to check this and won't be able to for at least a week. This may be the simple answer to my bending problem. I'll let you know.

Jeff
post #13 of 18
8/28/00 at 4:43pm
Jeff,

I have tried the "Frame Sync" toggle to try and cure the bending at the top of the screen. It does not help! Sorry.



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DMan
The Academy Home Theater
post #14 of 18
8/29/00 at 12:06am
Mark,

When I said using the Isco anomorphic lens for experimentations with the subject stated above, I meant the lens designed for video applications (expansion factor of 1.44 or there abouts) and not an standard Scope lens (expansion factor of 2.0x). Thus far, Alan is the only sabby and gutsy individual that I know of who has successfully added an standard film projection scope anomorphic lens to a video display in lieu of its own.
I think making the distinction is important, yes?

-THTS
post #15 of 18
8/29/00 at 4:05am
Thread Starter 
Although I have not yet tried the FRAME SYNC feature yet to see if this gets rid of the bend, it sounds like you guys have. To no success.

Bummer.

Still hoping for a solution.

Jeff
post #16 of 18
8/29/00 at 11:57am
Frank, sorry for the confusion. I guess I got confused reading Jeff's opening post to the thread talking about using the CI with "future 2.35:1 lenses".
post #17 of 18
8/30/00 at 8:53am
I also have the bending problem with an Ampro 3300. I have used the frame sync to minimize. Unfortunately, I must use the 640 X 480 output to minimize this problem. This is disappointing since the projector has 8" tubes and must use this lowest output setting. My technician says it is a CI problem.
post #18 of 18
8/30/00 at 12:03pm
Alan G,

Have you had any free time (ha,ha) to look into the bending at the top of the picture on the Crystal Image? It seems that more people are seeing this problem, and for me at lesat, this is the final hurdle that keeps the CI from being perfect. Ok, at least perfect to my eyes anyway. Thanks a bunch!



------------------
DMan
The Academy Home Theater
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AVS › AVS Forum › Video Components › Video Processors › Alan, The CI does do a "double stretch"