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Discussion Starter · #1 ·
1. Is it actual additional resolution or just same resolution spread on more pixels? Meaning will you actually see more picture detail with one of these configurations?


2. What is the best lens to use with an H79?


thx,

Jim
 

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Hi, Jim!


I can't help you with the Optoma, but I can talk about resolution and anamorphic lenses. Since your projector is a 720p machine, it'll obviously throw a 1280x720 image in 16:9 mode. With an anamorphic lens in place, those same pixels will be spread over a 2.35:1 aspect ratio. If the lens stays in place, 16:9 images will have a projected resolution of ~968x720. In other words, you'll see lower resolution in this particular case, not higher resolution.


However, let's think a bit more about 2.35:1 images. Without the lens, a 2.35:1 image would be projected at 1280x545. With the lens, this improves to 1280x720, so resolution really does increase here. What happens with this additional resolution depends upon the source.


For DVDs, the additional pixels will be used for interpolation (a "smoother" display). For 720p sourced 2.35:1 movies, the same will be true. However, with 1080i-sourced 2.35:1 movies on your 720p display, the resolution increase added by the use of the lens is real (2.35:1 movies in 1080i have a source resolution of ~1920x817)!


Cheers!

MarkF
 

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Discussion Starter · #3 ·
Ok so the extra resolution for a DVD is not really extra resolution its scaled so to speak to fit the whole screen. An obvious benifit is the lack of projected black light above and below the picture which I can't stand. But is not "real" resolution its just more pixels being used - right.


for 1080i sources such as DVHS there is actually more source resolution so you get more actual detail right? How about if your projector is a 720p machine though?


thanks,

Jim
 

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Quote:
Originally Posted by Jim Parys
Ok so the extra resolution for a DVD is not really extra resolution its scaled so to speak to fit the whole screen. An obvious benifit is the lack of projected black light above and below the picture which I can't stand. But is not "real" resolution its just more pixels being used - right.


for 1080i sources such as DVHS there is actually more source resolution so you get more actual detail right? How about if your projector is a 720p machine though?


thanks,

Jim
In addition to the extra pixels used you also get the benefit of more light output, how much depends on the quality of the anamorphic lens or prism.
 

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Quote:
1. Is it actual additional resolution or just same resolution spread on more pixels? Meaning will you actually see more picture detail with one of these configurations?
The source (DVD) will still use the same amount of pixels. The PQ increase comes when you spread those pixels onto the whole 16x9 panel. The vertical resolution is really important. That's why if you leave the lens on all the time even for 16x9 it's still looks great. You're still using all the vertical resolution just less horizontal which isn't as noticeable.


As was mentioned it will be a smoother picture with more punch and also brighter.


Check out these pics from Joe Przybylski with his Panamorph 752: http://www.avsforum.com/avs-vb/showt...&post5891774


Alot of the PQ increase comes from just proper masking of the 2.35 image. Having a proper black border all the way around helps alot.
 

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Hi, Jim!


Your last post is exactly correct on both counts! And yes, with a 720p projector, viewing 1080i-sourced 2.35:1 images with an anamorphic lens yields a genuine information increase as compared to not using the lens, from ~1280x545 to ~1280x720!


Interestingly enough, with a 1080p projector, adding an anamorphic lens does not add additional information at any resolution (only additional "scaling" pixels are added), since all of the source resolution is displayed whether or not the lens is used!


Cheers!

MarkF
 

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Nice posts, Mark...excellent.


While actual resolution for 2.35 DVD is certainly limited (maybe this won't be the case with HD-DVD?), using the entire panel reaps noticeable benefits in my setup despite the source limitation. When you consider the other benefits, it's certainly worth it. A no-brainer, really, at the 752's price.
 

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You are just spreading out the pixels to cover the entire panel... you cannot magically create more resolution when it isn't there to begin with. However, the benefit, besides the constant height setup, is more light output than before since the whole panel is used as others have stated. You will need it as an anamorphic lens will suck a small amount of brightness as is (use a good lens and you'll hardly notice the difference).
 

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Quote:
You are just spreading out the pixels to cover the entire panel... you cannot magically create more resolution when it isn't there to begin with.
Certainly true for DVD, as has been noted. I can see the difference is resolution when viewing a 1.85 anamorphic transfer in "letterbox" mode compared to 2.35. More pixels used for the image is better, though,...in addition to the other benefits. More brightness is not a concern for me, I use a filter to cut it down as it is.
 

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Here's my 64 thousand dollar question:


Do you feel the need to sit further back for 2.35 stretched presentations if your seating is optimal for 16:9?
 

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Me?


My seating (~1.7x width) is just about right for 2.35, so if the screen were even wider (as it would be if I'd optimized for 16:9 instead), I'd certainly be too close with this pj. I really think I need 720p or greater to strike a happier medium between the two AR's.

As I've stated, though, I find myself with mostly 2.35 DVD's, and I don't do TV or 4:3 much...very rare. So I'm happy with the size compromise for 1.85.
 

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Hi, Acksnay!


Projector resolution, source quality, and personal preferences all are significant factors in determining your "best" seating preference. Personally, I'm going through an interesting experiment: the seating distance with my new screen will be just 1.1 screen widths for 2.35:1!!!
 

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Quote:
Originally Posted by Mark J. Foster
Hi, Acksnay!


Projector resolution, source quality, and personal preferences all are significant factors in determining your "best" seating preference. Personally, I'm going through an interesting experiment: the seating distance with my new screen will be just 1.1 screen widths for 2.35:1!!!
Wow! That will be immersive to say the least.


My seating is about 1.3-ish for 2.35 and the picture fills my field of vision nicely. You'll have IMAX-at-home!


I believe the original poster's question regarding extra resolution has been covered, but I'll throw my $.02 in the ring:


I prefer the picture with my panamorph lens on 2.35 material than the "un-panamorphed" 1.85/16:9 material my projector displays natively. I think this is mostly the lens "smoothing" the picture, not the extra pixel resolution. As far as more detail in the displayed image, I think there is more preceived detail, but that's probably from the image being larger than standard 2.35 letterboxed.


There is a definite gain in picture brightness/saturation. It's akin to running my bulb on full output vs. economy mode (which I run it in).
 

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Hi, Gang!


Dan: As Jeff also mentioned, you're correct on DVDs, but not for 1080i 2.35:1 content on 720p projectors. That's a legitimate increase in information! Not, of course, by adding the lens itself! However, in the process of restoring the proper aspect ratio, you need to increase the size of the image through a scaler or HTPC. When that happens, additional scan lines of source material are "exposed" on 720p projectors. It's real!


Jeff: I don't want to hijack Jim's thread, but I will say this. Over the ~eight years that I've had an FP setup, I've gradually moved to larger screens. My old 16:9 was 117" wide; the new 2.35:1 is 141" wide. A big piece is the projector, in moving to a 1080p machine, and another major component is source quality (a combination of better scalers, better DVD player software, and better DVDs). However, preference also plays a part. There are two factors here. First, HD's very important to me, so I don't want to significantly reduce my 16:9 image size. Second, I really am changing, in the sense that over time, we're enjoying larger, more immersive images!


Have Fun!

MarkF
 

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Jack and Mark: thanks for tugging the bait, but sorry. I didn't budget enough for this question. :D I'll try again.


Here's my million dollar query:


Let's say I've got a CIH setup. There's a 10 foot wide 2.35ar screen. I'm watching 16:9 HDTV so I've got my masking on and all I can see is 7.5 feet of 720p content. I'm sitting back 4/3rds the screen width which puts me 10 feet from my 16:9 image.


Now it's DVD time. The mask retracts to reveal the full 10 foot 'scope. I'm still sitting 4/3rds back but now it's only 1 screen width away from the 21:9 image.


The scan line spacing hasn't changed. But the individual pixels have gotten fatter/wider due to horizontal stretching.


You know what? Forget it. This is silly. :eek: I've got the new HT down to stud and it's accessible enough to test this stuff out. I'll throw up the SP7210 / 120" 2.35 Firehawk / H1200M jury-rigged and I'll see for myself this weekend ...
 

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Quote:
Originally Posted by acksnay
I've got the new HT down to stud and it's accessible enough to test this stuff out. I'll throw up the SP7210 / 120" 2.35 Firehawk / H1200M jury-rigged and I'll see for myself this weekend ...
Hi acksnay-

I'm interested in hearing your opinion after your test. I'm building a new theater and have the capability of putting in a 2.35 screen up to 160" wide. But what's the point if I just have to move the seating back?


My eyeballs today are 12' from a 92w x 52h screen, so by width I'm at 1.3x. If I just look at height I'd like the image a bit taller even at the same distance, so when I move to CIH I'd like to go to at least 60" tall at the same distance. So 1.78 material would be 107w and my eyes would be at 1.1x. But then 2.35 material would be 141w and eyes at 0.85x. Like you, I may have to wait until I'm far enough along to try it, but it would sure help to be in the ballpark ahead of time, particularly for planning throw distance/PJ placement. Maybe I'll just try different seating distances with my current setup, showing a 2.35 movie on the 92w screen and assume everything ratios up.


If in the end the only reason to scale up is to fit more seats in the comfort zone, that doesn't seem worth it as I'll always be sitting in the middle front seat anyway :D
 

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Quote:
Let's say I've got a CIH setup.
You've got a CIH setup.

Quote:
There's a 10 foot wide 2.35ar screen. I'm watching 16:9 HDTV so I've got my masking on and all I can see is 7.5 feet of 720p content. I'm sitting back 4/3rds the screen width which puts me 10 feet from my 16:9 image.


Now it's DVD time. The mask retracts to reveal the full 10 foot 'scope. I'm still sitting 4/3rds back but now it's only 1 screen width away from the 21:9 image.
It sounds like you're too close for 720p, or DVD for that matter. I'm assuming your HD size is optimal for you, and that you've based your screen size on that, rather than your 2.35 image size. 1080p/HD DVD should make this much easier. :)


Definitely looking forward to your impressions...
 

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Hi, Acksnay!


With 720p content, the lens won't add resolution on a 720p projector - only additional scaling pixels. With 1080i content, though, let's walk through this.
  • Start without the lens, with a 720p projector firing at the 16:9 segment of a 2.35:1 screen
  • Fire up a 2.35:1 movie from a 1080i source. The 2.35:1 movie has a source resolution of 1920x817, but thanks to the limitations of the projector, the active display resolution will be 1280x545. At this point, the image is being shown "windowboxed", in the 2.35:1 section of the 16:9 segment of the 2.35:1 screen.
  • Move the lens into place. The pixels are stretched horizontally such the image fills the width of the 2.35:1 screen, but the aspect ratio is wrong.
  • To correct the aspect ratio, you'll need to use your scaler to increase the height of the image. As you do this, you will need to add (720 - 545 = ) 175 new scan lines, replacing the black bars at the top and bottom of the screen with new content.
  • Since the source resolution is still 1920x817, and the active display resolution is now 1280x720, the 175 new scan lines that were added are honest to goodness additional information!

How's that sound?


Cheers!

MarkF
 

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Hi, Acksnay!


Since you never really finished your question(!), I just realized that you may be asking not about resolution increase (as this thead assumes), but about visible pixellation. My previous projector was a 1365x1024 D-ILA running at 16:9, thanks to an anamorphic lens, so it already had a higher pixel density than 720p machines. With that setup, pixelation was not a problem at ~1.2 screen widths. However, remember that the D-ILA has a very high fill factor, and I had a 52% higher pixel count than a 720p machine.


I would not consider moving to my new 1.1 (actually, about 1.05) screen widths distance unless I were also moving to a 1080p projector. Other folks may be different, and not as concerned about pixellation or other digital artifacts. How you will like the image is entirely up to you, and you alone!


Have Fun!

MarkF
 

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Sheesh! What a night. Made temporary camp in the space-that-will-be an HT room. Hooked up an HD cablebox and DVD player to an InFocus 7210 throwing onto the Firehawk.


I saw less pixel structure from 4/3rds back on the DC3 720p PJ than I did from 2x screen widths back on the DC2 480p PJ.
But all other things were not equal. Certainly my old 6' wide HCCV is not the equal of this newly formulated Firehawk. I tried, but could not see any sheen/sparklies/hot spotting in the usual scenes (sky pans, snow fields). So this screen is definitely helping; much less granular than the HCCV. Unfortunately from this close up, motion artifacts and compression garbage is a bit more intrusive. I'm still about 25% too bright (16 ft/L with an ND2 filter on), so there's room for quieting that down too.


This Firehawk is dark. Surprisingly dark. So much so, it may not need masking. (!)


Still haven't used the Prismasonic H1200M. Will need to jigger-up some sort of temporary bracket to keep it in place so I can take this to the next level.


Bottom line so far: 4/3rds back (1.333 screen widths) in this setup for 16:9 HD is beautiful. The WAF was suitably impressed. Come to think of it, so was I. :D And compared to true HD, DVDs performed as I've come to expect: slightly less overall color depth, some muddying of finer detail, but without additional issues of noise or pixel structure.

Jim: It wasn't my intent to hijack your thread. But if it helps, I'll take some screeen shots with and without the lens in place.
 
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