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Discussion Starter · #1 ·
I have a Panamorph 2 on order (235:1 AR) and have come to the decision to use only this lens combined with a 235 screen. I will then scale everything (16:9 and 4:3)inside using YXY on my HTPC.


How many of you are planning to do this and what might be the downside to such a decision? Smaller 16:9 and 4:3 images are no problem. I can't think of a reason why not. Only advantages.


Thanks,



Jeff
 

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Jeff,


The downside is lower resolution for narrower media.


With a fixed height, variable width image like you are proposing the vertical resolution is fixed, but to work with the 2.35:1 lens' vertical compression, the panel's active horizontal image area has to be "sideboxed" to maintain the proper proportions.


I could do the math, but I won't. http://www.avsforum.com/ubb/wink.gif


Suffice it to say that the horizontal resolution of 16:9 material would be about 25% less, and 4:3 material would be almost half of the full panel's horizontal resolution.


I have my ISCO I lens which I will be keeping with my G15 for 16:9 material and 4:3 material (at lower horizontal resolution), and I'm going to be using my upcoming Panamorph II lens for 2.35:1 material. Hopefully I'll build some rail setup to swap between the two lenses.


Realistically, most of the 4:3 media is well under the resolution of scaled DVDs, so it may not be a great loss, but we will have to see when the Panamorph II ships.


-Dean.
 

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Dean,


Have you heard anything from Shawn about variable compression on the PII ? I don't know how I missed it with regards to the Panamorph I, but it was news to me that tilt actually provides a range from 1.65 to 1.78 on the Pannie I.


I am wondering what the range on the PII will be, or if it will be a fixed compression affording 2.35 only. If there is some range, then a tilt on the PII might mean only a little loss on 16:9 material.


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Kirk Ellis

G1000 D-ILA, HTPC, Panamorph (soon I hope),

Dish 6000 (HBOHD,SHOHD,CBS,NBC,ABC,WB,FOX,UPN, KCET -- does it get any better ?)
 

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Kirk,


Actually, Shawn has never actually corresponded with me yet.


But he made comments in a previous 752 thread a couple weeks ago about getting the P561 (their name for the PII) out of the prototype stage.
http://www.avsforum.com/ubb/Forum10/HTML/008004.html


It would be nice if the P561 also has the same fine tuning feature for a variable aspect ratio as the 752, but at about 10% variance it wouldn't make too much of a difference either way.


Still, I'm holding judgement of the P561's picture quality and other adjustment features until it is in my hands (soon I hope).


-Dean.
 

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Jeff,


Since you know the compromises involved with that setup it sounds fine it to me.


My solution to the screen problem has been to go with a Stewart that has variable heigth and variable masking at the top as well. I'm just hoping the 235 lens will work easily with the 752 on a rail system. My trade off will be 4x3 within a 16x9 screen since thats the maximum height I opted for. A 4x3 104" wide would have been simply too tall. My only "upgrade" now would be to spend another 2K on a set of black center draw drapes to hide the white portions on a 4x3 pic. But, that will be tricky to mount. I'm still waiting for the new screen from Stewart (supposedly shipped tuesday) and the black (one way pull) velvet drapes to go behind it.


I thought this solution for me had the fewest tradeoffs.


I wonder what Shawns current thinking is on a combination 16x9 and 235 lens is now? If he decides he wants to just make that rather than a seperate 235 lens, that might not be a bad idea if it's EASILY switchable. I could then resell my (not here yet either) 752 to someone that has a 16x9 paneled projector. I too have a preorder for the 235 version.


Larry


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DFAST is EVIL! BOYCOTT ANTI-CONSUMER 5C/DVI/HDCP/DMCA MANUFACTURERS!

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[This message has been edited by videohot (edited 08-24-2001).]
 

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Discussion Starter · #6 ·
Thanks guys.


I never thought of the loss in res on 16:9 material (I don't really care about 4:3). I think I can probably live with it for simplicities sake. Combined with a little tilting of the P2, I should come up with a nice compromise that won't affect it that much.


Thanks again,


Jeff
 

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Hi Jeff,


I don't know if you saw it or not, but Alan posted some pics and impressions of a constant 2:35 setup he has using a Seleco, an ISCO and a Panamorph. http://www.avsforum.com/ubb/Forum10/HTML/008224.html


I was considering a 2:35 Panamorph instead of the 16:9 but I decided against it. Mainly because of how my projector, a Davis DLS8, handles HDTV signals. I don't have HDTV capability yet, but from what I've read here, the Davis takes a 720p signal and stretches it to fill the entire DMD panel. A 16:9 anamorphic lens would reproduce the original picture perfectly, but a 2:35 lens would over stretch it, making it useless for HDTV. Since I can't use YXY to scale HDTV material, a 16:9 lens would be more useful for my setup.


I don't know how your projector handles HDTV, but it is something to consider.


Hope this helps,

Tony
 

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Hi Guys.


I too have the 2.35:1 Panamorph on pre-order. My plans are to use both of the Pannies on a single track (please make this possible shawn).


My screens slide on a track from the adjoining room, allowing me flexibility in screen size and aspect ratio without masking. The 16:9 Grayhawk is 47x89, and the 2.35:1 DIY (JoAnne's blackout) will be 45x106. Zooming the Dila will be required to change from one screen to the other- no big deal as long as the Pannies are parfocal.


I entertained the thought of using only the 2.35:1 Pannie, but decided that optimization dictated using both lenses (at considerable cost, of course).


Leaving the 16:9 Pannie in the system will also allow me to use a DVD player instead of the HTPC in the case of a computer crash/meltdown. Tonypeps makes a similar point regarding HDTV- demonstrating that the 16:9 lens is a more mainstream choice. 4:3 will also be best on the 16:9 lens.


If Shawn could somehow make the 2.35/16:9 combo mentioned by Larry, that would be ideal. I think I recall him saying that it was not possible, or perhaps just beyond the scope of the current project.


Jeff Streitz

Iowa City, IA
 

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I have a 2.40 screen and I will be using my preorder 2.35 panny to do constant height as you have suggested. I am doing that now with my ISCO-2 so I am already used to it. I'll just be getting a brighter picture.


As far as loss of resolution, it's not visible on the 1.85 stuff and the 1.33 source stuff is of such low resolution that it isn't noticeable there either.


Hope this helps,

Phil
 

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Jeff,


Yeah it's probably going to be a fairly minimal resolution loss with the formatting addustment via tilting, I just thought that I'd mention it because it was a consideration when I got my first ISCO lens.


Larry,


I'm not sure that there is enough format adjustment range to span between 1.78 and 2.35:1 ratios without some image distortion problems, and I'm hoping that Shawn is not still in the design reevaluation stage of product development with the P561 at this point (I'm hoping that they will be built and shipping soon).


I think that Shawn had mentioned previously that the P561 was the first 2.35:1 lens design, and was a partner lens to the 752 designed for fixed width HT setups to work best when retrofitting to existing HT rooms where the projector and screen are already installed.


He had mentioned a second, future 2.35:1 product which would combine vertical image compression AND horizontal expansion in one lens.


Tony,


Yes, if the projector has no way (like my LT-150) to stretch a HDTV feed past full picture height, the 2.35:1 P561 won't work for HD movies.


My G15 can be tweaked using Dilard to do it, but I'll probably just use my ISCO 16:9 lens for HDTV and 1.85:1 material and have the P561 soley for 2.35:1 DVDs.


-Dean.
 

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Jeff,


The downside is lower resolution for narrower media.


With a fixed height, variable width image like you are proposing the vertical resolution is fixed, but to work with the 2.35:1 lens' vertical compression, the panel's active horizontal image area has to be "sideboxed" to maintain the proper proportions.


I could do the math, but I won't. http://www.avsforum.com/ubb/wink.gif


Suffice it to say that the horizontal resolution of 16:9 material would be about 25% less, and 4:3 material would be almost half of the full panel's horizontal resolution.


I have my ISCO I lens which I will be keeping with my G15 for 16:9 material and 4:3 material (at lower horizontal resolution), and I'm going to be using my upcoming Panamorph II lens for 2.35:1 material. Hopefully I'll build some rail setup to swap between the two lenses.


Realistically, most of the 4:3 media is well under the resolution of scaled DVDs, so it may not be a great loss, but we will have to see when the Panamorph II ships.


-Dean.
 

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Dean,


I had thought Shawn mentioned at some point he would be trying to do a combination lens. Ohh well.


Did you ever take any pics of your ISCO II pics with test images similar to what is in this thread?

http://www.avsforum.com/ubb/Forum10/HTML/008359.html


I have been waiting for tommyboys review for some time now but it looks like he's busy.


I am not thrilled about the distortion shown in the pics within that thread and now am not sure the 16x9 Panny is my best option. Have any thoughts on what you see there vs the ISCO II?


Larry


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DFAST is EVIL! BOYCOTT ANTI-CONSUMER 5C/DVI/HDCP/DMCA MANUFACTURERS!

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Larry,


From reading the other thread it looks like that distortion is being introduced by tilting the lens to get a 1.78:1 ratio.


I haven't actually seen the 751/752 Panamorph, so I can't say for sure, but a fresh install setup probably won't have those distortion issues.


I also had compromises installing my ISCO lens. I had to mount my projector 1 foot down from the ceiling to clear plumbing in my basement HT, and so I has to compensate by angling the projector and lens to work with the D-ILA, which has a fixed ceiling/floor lens angle.


I have the ISCO I lens, which has more pincusioning than the ISCO II that I've seen, but the distortion is still far less in the active picture area than the other thread's Panamorph picture shows.


-Dean.
 
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