How is the image quality of 16x9 content on a curved screen?

I had same thought, did some study a while back, look here, this may answer your Q's, at least give you additional info:
Study: Native 16:9 vs a-Lens/PJ Scaler

Simply, I find watching 16:9 images w/o a-lens on my curved screen no issue.


I also don't perceive any distortion due to a curved screen while watching 16:9 (1.78:1) content onscreen, here is test pattern 1.78:1 w/o a-lens, PJ in full mode:

I leave my lens in place all the time as I find the barreling on my curved screen when the lens is removed to be annoying.

Are'nt you losing 33% of your 16:9 and 4:3 pixels by leaving the lens in place for these formats?
This defeats your whole argument about utilizing the maximum number of panel pixels!

Not really, since the loss in horizontal resolution isn't nearly as noticeable as the loss in vertical resolution - at least that's what's been reported by people who have actually done this, including me. Plus you get the benefit of maintaining equal brightness and pixel density regardless of what aspect you're watching.

I am actually doing what CAVX is doing as well and I can
attest that it is not noticeable at all during movie watching.

However, if you display an HTPC desktop @ 1920x1080 and in 4:3 with the lenses in place then text clarity is obviously compromised. In video material though I am impressed how "I CANNOT" notice the difference.

No matter what, I leave the lenses in place and choose 4:3 on the projector since the curved screen makes the horizontal bar on my HTPC look bad and it was pissing me of a lot! The same happens in some games that use horizontal bars (if you care).

My screen is a Stewart cine-curve and I noticed that you can adjust the curve radius by a fair bit but this is not something you want to do more than once since it requires unscrewing it and flexing it which is not logical to do all the time.

So after not much thought () I went ahead and ordered another Stewart (cabaret) motorized screen so I can use a Dual-Screen solution but honestly I think I went too far this time and it is not "really" needed.

On the bright side, I opted for the RGB LED lighting that Stewart offeres on the Cabaret and went for a Firehawk material which should help watch material with low lighting or make the screen a high end RGB LED strip.

So it's perfectly OK to lose 33% of your pixels when using an A-lens (plus vertical stretch) for 4:3 and 16:9 projection, but it's not OK to lose 33% of the pixels when using the zoom method for 2.35?
Can someone point me to a technical expanation of why the eye is more sensitive to vertical resolution than horizontal, because right now I think this whole explanation is a bunch of hokum.

Its actually 25% for 16:9 (1920 x 0.75 = 1440) and the full width for Scope. The key point is that the image maintains the full 1080 vertical rez regardless of AR and the pixel density per square unit remains the same as has been stated many times.



Zooming takes you from 1080 back down to approx 810. Given the choice between 810 and 1080, I'll take the 1080, thanks.

Well, you have a lot more horizontal lines to begin with (almost twice as many as vertical columns). So loosing vertical columns becomes more critical.

Also, keeping the lens in place keeps the exact same pixel size as you switch ratio. If the resolution is ok for scope it should be for 16:9 as well as the pixel size is the same. In contrast, if you zoom you get smaller pixels for for 16:9 movies than scope.

Exactly.

quote: [Also, keeping the lens in place keeps the exact same pixel size as you switch ratio. If the resolution is ok for scope it should be for 16:9 as well as the pixel size is the same. In contrast, if you zoom you get smaller pixels for for 16:9 movies than scope. ]

Is'nt a smaller pixel size (for 16:9 and 4:3) desirable ?
You cannot have it both ways, saying that losing pixels by using the zoom method for 2.35 is bad, but losing pixels by leaving the A-lens in place (with vertical stretch) for 4:3 and 16:9 is somehow not detrimental to PQ. If what you say is true, why do people bother buying Cineslides?

Because is difficult mentally not to use the full resolution even if you actually can't tell the difference on videomaterial?

Of course you will lose some real world resolution, but how visible is it? Does it out weigh the drawbacks associated with shifting the lens out of the way? My point was if you're perfectly happy with the resolution and pixel size of the scope presentation, it won't get any worse keeping the lens in place for 16:9 or 4:3.

What you gain is less hassle shifting ratios, the same brightness and pixel size irrespective of aspect ratio, and you avoiding barrel distortion on a curved screen.

Heavens forbid!

I've also just stretched 16:9 to 2.35:1 via leaving the lens in place and watching the HDTV like that (in this instance sporting event).

Yea, I was too lazy to put up my manual masks or slide the lens out of place.
It's on my "to do" list motorized slide and masking......


Sure, on close up people have that "stretched fat look going on".....

I think your still missing the point. Lets say you have a big screen that makes your pixels 2mm tall (Screen would therefore be 2160mm high).

1. Moving the A-Lens for Scope:
Scope uses 1920 x 1080 pixels where each pixel is 2.66mm x 2.00mm.
HDTV uses 1920 x 1080 pixels where each pixel is 2.00mm x 2.00mm.
4 x 3 uses 1440 x 1080 pixels where each pixel is 2.00mm x 2.00mm.

Pixels for Scope become 33% wider. Lens pending, there may be a percievable difference when the lens is moved into the light path.

2. Leaving the A-Lens in place all the time:
Scope uses 1920 x 1080 pixels where each pixel is 2.66mm x 2.00mm.
HDTV uses 1440 x 1080 pixels where each pixel is 2.66mm x 2.00mm.
4 x 3 uses 1080 x 1080 pixels where each pixel is 2.66mm x 2.00mm.

The only change is total pixel count for each AR. Pixel density, calibration setting etc, remain the same.

3. The Zoom Method:
Scope uses 1920 x 810 pixels where each pixel is 2.66mm x 2.66mm.
HDTV uses 1920 x 1080 pixels where each pixel is 2.00mm x 2.00mm.
4 x 3 usies 1440 x 1080 pixels where each pixel is 2.00mm x 2.00mm.

So not only does the biggest image now have the least number of pixels producing it, their individual size is some 78% larger than the pixels making all other ARs.

4. The Shrink Method:
Scope uses 1920 x 810 pixels where each pixel is 2.66mm x 2.66mm.
HDTV uses 1440 x 810 pixels where each pixel is 2.66mm x 2.66mm.
4 x 3 usies 1080 x 810 pixels where each pixel is 2.66mm x 2.66mm.

Whilst this method produces the largest pixels, those pixels do not change shape or size so like when leaving the A-Lens in place (#2), pixel density remains the same.

So the pixels stay the same size, So what? There's still 33% less of them for 16:9 and 4:3! Your whole premise for the advantage of the A-lens over the zoom method is that you are using more of the panels pixels. Yet, the loss of horizontal pixels resulting from leaving the A-lens in place for 16:9 and 4: 3 is apparently a non-issue to you. No wonder people like me find the whole A-lens issue clouded by confusion and speculation.

No, you're just purposely trying to obfuscate the the issue. Plenty of people understand the benefits of using an anamorphic lens in certain scenarios.

And your STILL missing the point. 1080 vertical pixels for all ARs. 1080 vertical pixels that never change shape or size. That is why the lens is used in the first place - to max out the vertical rez for Scope films that otherwize WASTE these pixels on black bars. 1080 is why HD is High Definition. If this did not matter, we might have well just stayed with SD's 480/576 lines.

CAVX, don't waste your time.

This topic has been beat to death on this forum and you are never going to convince certain people here that the advantages of leaving a high quality anamorphic lens in place all the time carries far more positives then negatives.

Those of us that have this setup know that this is the path to anamorphic nirvana.

Some members simply refuse to acknowledge this and, interestingly enough, most of these people have no actual experience with this configuration, but merely rely on the theoretical to justify their position.

Vern

So it's only the vertical pixel count that determines PQ, not the horizontal pixel count?
You are saying that the reduction in horizontal pixel count, when using the A-lens in place for 4:3 and 16:9, has no effect on PQ? There is just no way that can be true.
What you are doing is sacrificing 4:3 and 16:9 PQ for the expediency of not having to move the A-lens. That's fine if you want to do it, but please don't say you are not losing PQ by doing that.

Yes and also making it more difficult than needs to be. YES you can move the lens out of the path and add back the 1920 lines of res. and all the extra focused light for 16/9. But really for 16/9 or 4/3 really dont care that much as the middle of the screen of the 2.40 image looks great so 16/9 will look exactly the same.

Take what you watch more 16/9 then sure move it if you wish....I don't see a difference and rarely watch 16/9 so I leave it in place. Simple, incredible looking, awesome experience. Enjoy your setup that's right for you.

NOT loosing picture quality over the 2.40 image YES.

I should do as Vern has suggested and just walk away. Taffman, you'll never be convinced simply because you do not have such a lens and therefore have not seen what it is I (and other members) are talking about.

What I am saying is that the PQ does not decrease from the level obtained. Your best picture is going to be a 1.78:1 full frame image.

When I fire up my projector, my image is of a high level. That level does not change regardless of AR. You like to ASS-U-ME anamorphic lenses destroy PQ. From what you have posted, this assumption is based on your experience with a 2x film on a 16mm projector. Whilst there are SMPTE loops made for astigmatism adjustment, you will never get that adjustment as good as what can be achieved using single display pixel lines on a 1080 digital projector. Unless they made a special slide that I am unaware of, and even if they did, I doubt the lines could be that fine. And I base this in the fact that I've worked with both 16mm and 35mm film projectors.

I am able to adjust my lens to bring both horizontal and vertical single display pixel lines into focus at the same time simply because I am able to connect my PC (Via HDMI) and have generated my own test pattern at 1920 x 1080 pixels. I display this at 1:1 for this adjustment.



The ONLY limitation to my optics is the lens of the BenQ W5000!

As for the smaller ARs. If a scene in a film was a blackened room and a door was suddenly opended letting light into a smaller section of the screen, does the PQ suddenly become less? The answer is of course NO. Side pillars have the same effect - NONE. The fact that they are not active simply means that they are not reflecting light onto the screen in those areas. The parts of the screen that are illuminated will be as bright and as pixel dense as when the the full panel is used.

Damn! The more I think about it the more I realize that the second screen I am getting was necessary NOT!

Whilst I have posted lots Scope screen caps, I might have to post some 16:9 shots as well. Give me a few days.

You will have side pillar bars with 4: 3 films no matter whether the lens is in place or not. On the screen, the 4: 3 image is the same size regardless. The difference is that the image with the lens in front of it will be composed of 33% LESS horizontal pixels than if you do things normally and move the lens out of the way. The A-lens people have always maintained that the advantage of the A-lens is that it utilizes all of the projectors panel pixels, but apparently some of them have have convinced themselves that this only applies to 2.35 :1 images!

Taffman, if your going to post your point of view, then please use the correct maths so as not to mis-inform others. You HS scale by 25%, not 33%. You then optically expand by 1.33x to restore the geometry.

OPTICAL 16:9 is obtained by:

Scaling: 1920 x 0.75 = 1440
Optics: 1440 x 1.33* equates to the same width as 1920.

HE A-Lenses do not barrel (convex), they pincushion (concave). The amount of pincushion of the verticals is hardly noticeable where it is in the horizontal and why many of us feel the need to curve our screens.

I don't have side masks on my system simply for the fact that they would be open more times that they were closed due to the fact that most program I watch is Scope. The last film I watched that was not Scope was DISTRICT 9. I don't find the side pillars as distracting as letterboxing bars are.