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post #61 of 1307 Old 06-17-2017, 01:14 PM
 
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Originally Posted by Eternal_Sunshine View Post
The point is that the resolution of the lens needs to be "finer" than the shifted pixels, because otherwise you couldn't shift those pixels in such small increments. The time when this happens is indeed irrelevant.
What if I was to use a tiny amount of lens shift? Your argument doesn't make sense.
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post #62 of 1307 Old 06-17-2017, 01:15 PM
 
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Resolution requirements for lenses

Quote:
Originally Posted by Eternal_Sunshine View Post
The point is that the resolution of the lens needs to be "finer" than the shifted pixels, because otherwise you couldn't shift those pixels in such small increments. The time when this happens is indeed irrelevant.

The lens resolves the native resolution anywhere on the surface of the lens (with slight reduction as you move to the outer edges), so it doesn't matter in the least whether that native resolution slides slightly right and up, especially only a freaking half pixel!

If what you're saying were the case, you'd need a new lens every time you used some lens shift to move the image on screen, because the image placement on and through the lens changes as you do!

P.S. - oh Seegs beat me to it.
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post #63 of 1307 Old 06-17-2017, 01:25 PM
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No. Lens shift shifts the whole (same) picture around, e-shift shifts a different picture by an extremely tiny amount and needs to be extremely precise in doing so, while still also projecting the original picture in the original space. This is in no way comparable.
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post #64 of 1307 Old 06-17-2017, 01:49 PM
 
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Originally Posted by Eternal_Sunshine View Post
No. Lens shift shifts the whole (same) picture around, e-shift shifts a different picture by an extremely tiny amount and needs to be extremely precise in doing so, while still also projecting the original picture in the original space. This is in no way comparable.

It still only flashes one sub-frame, then blanks itself as the eshift optical glass shifts, then flashes the second sub-frame up and to the right, in a slightly different position on the lens, milliseconds later.

The lens is only resolving the native panel resolution at any given point time, no matter how small that amount of time is, (or the position on the lens more or less) up until that point at which the shift happens at the speed of light anyway (one tidbit the telescope optical person shared with me).

He mentioned something about his software saying that it would be like 300 million frames per second! I am sure that lowers as the quality of the lens decreases, but still.
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post #65 of 1307 Old 06-17-2017, 02:04 PM
 
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Quote:
Originally Posted by Eternal_Sunshine View Post
No. Lens shift shifts the whole (same) picture around, e-shift shifts a different picture by an extremely tiny amount and needs to be extremely precise in doing so, while still also projecting the original picture in the original space. This is in no way comparable.
I think you're missing the point. There is only ever a 1080p image passing though the lens at any given time. The pixels remain the same size no matter what and due to how eshift works with a 1080p panel you don't have the chroma and luminance resolution as a native 4K panel has therefore there isn't actually a ton of finer picture information that needs to be resolved. There actually isn't the "smaller" pixel information you're arguing there is.
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post #66 of 1307 Old 06-17-2017, 02:11 PM
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But still, if the resolution of the lens is too low, the complete (and completely different) information of the second frame cannot be projected in the "slightly different position". You need to realize that the amount of how slight this difference in position can be – while still accurately presenting different information – is equivalent to the resolution of the lens.

And yes, there is smaller pixel information, gathered from the original 4K source, otherwise e-shift wouldn't be sharper / have more picture detail than 1080p. Producing this smaller pixel information is indeed the whole point of e-shift.
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post #67 of 1307 Old 06-17-2017, 02:16 PM
 
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Originally Posted by Eternal_Sunshine View Post
But still, if the resolution of the lens is too low, the complete (and completely different) information of the second frame cannot be projected in the "slightly different position". You need to realize that the amount of how slight this difference in position can be – while still accurately presenting different information – is equivalent to the resolution of the lens.

And yes, there is smaller pixel information, gathered from the original 4K source, otherwise e-shift wouldn't be sharper / have more picture detail than 1080p.
This is no different than how "slight" your image might come in and out of focus while watching a movie due to everything expanding and contracting due to heat build up inside your projector. As you put it, it's extremely slight and not something you'd physically be possible to see from a seated distance back.
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post #68 of 1307 Old 06-17-2017, 02:28 PM
 
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Originally Posted by Eternal_Sunshine View Post
But still, if the resolution of the lens is too low....
We've already established that it isn't "too low" for the native resolution of the panel. (2K or 2.7K)



Quote:
Originally Posted by Eternal_Sunshine View Post
.....And yes, there is smaller pixel information, gathered from the original 4K source, otherwise e-shift wouldn't be sharper / have more picture detail than 1080p. Producing this smaller pixel information is indeed the whole point of e-shift.

That all happens AFTER the lens with eShift. In our brains. Just as interlacing does. It's a trick that relies on human persistence of vision.
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post #69 of 1307 Old 06-17-2017, 02:48 PM
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Ok, I give up. I thought I might be able to explain it better / in slightly simpler terms than the technical experts, but apparently not. In the end, all that matters is what's on the screen. Have fun guys.
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post #70 of 1307 Old 06-17-2017, 02:57 PM
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Originally Posted by Dave Harper View Post
A. Flash the two native sub-frames at the same exact moment in "time"....

Then you must move to a higher resolution lens with greater MTF
I like learning new things and will admit if I am proven wrong, but in this case I think it would be useful for everybody to hear what this expert says is the lens factor that would need to improve if both eShift images were sent at the same time. Is there a name for it? What is the driving force that would require a better lens just because the eShift images weren't separated in time?

I've reached out to somebody who actually works on eShift projectors and should know this kind of thing, but I don't know if I will have permission to post any response.

Thanks,
Darin
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post #71 of 1307 Old 06-17-2017, 03:13 PM
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By the argument that all that matters is what goes through the lens at a moment in time it seems to me that if somebody built a single chip DLP with 4K resolution, but where it only displayed 2K images (replicating each pixel 4 times) by turning on 1 of the mirrors in the 4 pixel blocks, then the lens would have to be the higher quality lens for the smaller pixels in 4K vs 2K.

In case that wasn't clear, if we lettered each of the pixels in the 4K resolution as A, B, C, and D, this projector would display all of the As, then all the Bs, then all the Cs, then all the Ds.

Everybody believe that this would require a better lens than a 2K version that showed all pixels at once, all else being equal?

--Darin
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post #72 of 1307 Old 06-17-2017, 03:20 PM
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Simply put, until such time as the size of one single pixel hitting the rear lens element changes; becomes 4 times smaller for eg than a standard 1080p pixel, then the lens does not need to be any higher quality so long as the lens was originally able to resolve 1080p with 100% MTF.

If the argument of projecting two eshift frames at the same identical time could somehow actually create a new and smaller unique individually addressable pixel than a single larger standard 1080p frame (which it cannot, since this would be impossible) then the lens would no longer be resolving a single pixel the size of 1080p on the rear element; it would be a real UHD pixel on the rear element thus the MTF requirement will now be higher. But this scenario does not happen in real life unless you have a native 4k panel.
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post #73 of 1307 Old 06-17-2017, 05:06 PM
 
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Resolution requirements for lenses

Let me see if I can find it and if I understood it right, but he said it can matter due to coherent and incoherent light and whether they interact.

Here: (the first blue bubble with quotes is what he said earlier and that I quoted back to him for clarification)....



I think I understood it all correctly. So the coherent light coming through from each sub-frame at the same instant in time would interfere with each other and reduce the lens' resolution, thereby needing a higher quality lens, but if they are sent at different times sequentially, then they won't interfere and you'd just need the lens to resolve the native resolution.
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post #74 of 1307 Old 06-17-2017, 05:29 PM
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Thanks Dave.

My thinking this whole time is that a person could create a scatter pattern for the even eShift frames and a scatter patterns for the odd eShift frames, then add those whether they go through the lens at the same time or at different times, since I'm sure we are talking about incoherent light here.

Direct laser projectors have coherent light, but laser phosphor produces incoherent light and UHP bulb projectors create incoherent light. The wavelengths these let through for blue, green, and red are fairly wide band. As we get closer to REC.2020 the bands need to get narrower, but we are not there yet.

Each eShift subframe can be providing a lot of light which can already have interactions, like if the even subfranes account for 100 lumens and the odd subframes for another 100 lumens.

The question I would have for your expert is this.

If an eShift projector has a UHP bulb with fairly wide filters for blue, green, and red, could the scatter patterns from the even eShift subframes be added to the scatter patterns from the odd eShift subframes to get an overall scatter pattern? Would the ability to add those to get the overall performance be affected by whether these subframes went through the lens at the same time or not?

Thanks,
Darin
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post #75 of 1307 Old 06-18-2017, 09:43 AM
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Here is my post from the under 3K thread which spells out what the .66 TI 4K chip requires in the way of a lens to fully resolve the images it's capable of producing :

Line pairs in optics consist of a white line followed by a black line. In terms of pixels in a row, the same concept applies...pixel on followed by pixel off. If all the rows in a panel are made the same way, vertical line pairs appear. In the case of the TI .66 DMD TRP16:9 chip, with 2716 pix per row, the needed-optical resolution is exactly 93 lp/mm. Were there 3860 pix/row in the same DMD size, a considerably higher lp/mm would be required.

The spec, then, on a lens with an MTF of 93 lp/[email protected]% for this chip would look like this:

DLP TRP 4K diag, full size.........0.67 16:10
DLP TRP 4K diag, video size......0.66 16:09
DLP TRP 4K diag. video size.......16.7640mm
Px per line......................................2716px
Number of lines.............................1528 lines
Aspect ratio..................................1.7775:1
Tot number of Px...........................4150048px
base.............................................. ..14.6111mm
height............................................ ..8.2201mm
pixel size.........................................0.005 4mm
1 line-pair size................................0.0108mm (1px on - 1px off)
Line-pairs/mm................................92.94 lp/mm (horizontal resolution)
Vertical Resolution.........................92.94 lp/mm (same as horizontal resolution)

The fact that the 4k image is comprised of two sub frames in ultra-quick succession does not reduce the lp/mm requirement of 93. You can get away with a lens that is inferior to this -- and it is probable that the bang-for-buck projectors have lenses well below the 93 range, but the picture will be progressively softer looking as the number decreases. It is disappointing that most TI partner manufactures do not list this qualitatively important lens specification.

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post #76 of 1307 Old 06-18-2017, 10:20 AM
 
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Quote:
Originally Posted by Eternal_Sunshine View Post
Ok, I give up. I thought I might be able to explain it better / in slightly simpler terms than the technical experts, but apparently not. In the end, all that matters is what's on the screen. Have fun guys.
I think the big question here is by how much the lens' optical resolution is limited by diffraction effects. Two point sources at different times won't interfere with each other, but shown at the same time, would:

http://www.physicsclassroom.com/clas...e-Interference

If one only thinks about light as a particle (rays), then obviously, two DMDs offset by a half pixel would require a lens that's twice as good as a single DMD, in order to resolve all the detail from both (simultaneously or not). the big thing that makes all this way more complicated is the fact that two point sources actually do interfere with each other, so XPR avoids that.

I'm not at all sure any more and would much rather leave it to an actual physicist or lens designer. (or even better, more than one). I could log in to TI.com and ask them there, they'll surely know.
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post #77 of 1307 Old 06-18-2017, 12:38 PM
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Quote:
Originally Posted by RLBURNSIDE View Post
I think the big question here is by how much the lens' optical resolution is limited by diffraction effects. Two point sources at different times won't interfere with each other, but shown at the same time, would:

http://www.physicsclassroom.com/clas...e-Interference

If one only thinks about light as a particle (rays), then obviously, two DMDs offset by a half pixel would require a lens that's twice as good as a single DMD, in order to resolve all the detail from both (simultaneously or not). the big thing that makes all this way more complicated is the fact that two point sources actually do interfere with each other, so XPR avoids that.
This problem you point out requires the same mistaken assumption that Dave's expert made. It requires coherent light and we are using incoherent light (other than direct lasers). As it says there:
Quote:
It is also important that the two light waves be vibrating in phase with each other; that is, the crest of one wave must be produced at the same precise time as the crest of the second wave. (This is often referred to as coherent light.)
Also, XPR doesn't avoid light interfering with itself. Each subframe already has over 2 million points (if we count pixels as a point for the moment) that can interfere with each other. All of these different wavelengths and different point sources create a kind of randomness that basically makes it impossible for the effect you mentioned to be a real problem. That is why the experiment requires just 2 points and coherent light, like from a monochromatic laser, as mentioned at your link.

--Darin
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post #78 of 1307 Old 06-19-2017, 11:32 AM
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I'm hoping we'll hear from Dave's expert again once the assumption about using coherent light is fixed. We are normally talking about light that is fairly incoherent around here (but not totally incorehent). As his expert said, if the light is incoherent it can go through the lens at the same time. This would mean that with incoherent light both XPR sub-frames could go through the lens at the same time or different times and the requirements would be the same. The whole disagreement IMO has been whether it matters whether the two sub-frames go through the lens at different times or at the same time and here is Dave's expert saying that if the light is incoherent then it doesn't matter.

With light that isn't coherent if there is no difference between sending one sub-frame at a time or both together, then the expert's position that all that matters is the optical resolution falls apart because now 2.7k flashed at 2 different times and offset by half a pixel becomes the same as 2.7k flashed at the same time with offset by half a pixel and the optical resolution of the second case is much higher than just 2.7k (since they go through at the same time). Looks like the expert would have to agree with me once incoherent light is included that the requirements are not the same for one 2.7k frame only as two different 2.7k sub-frames offset by half a frame and flashed at different times. That works out from just basic logic at that point.

If I was asking the questions I think this expert's view that, "Thats because its not an optical resolution, but a perceived one" would fall apart pretty quickly. I often see where experts are used to using certain rules and when given a new situation they fail to look outside the box and use the same old rules, even though they don't work for the new situation.

My E3 example proves that just going by the "optical resolution" for a moment in time is not good enough to solve every problem.

For example, for cases like these:
Quote:
A company is hired to design a projector that will display an E or a 3. The projector will be black and white using a UHP bulb. The chip used will be 5 pixels wide and 7 pixels tall. The E or 3 will have 11 pixels set as white out of the center 3x5 pixels.

Both cost and performance matter for this projector.

Scenario A: The projector should be designed such that when an E is shown 95% of viewers with 20/20 vision viewing the E of height x off a screen and sitting at distance y will be able to identify the item off the screen. The lens for the projector should not be more expensive than required to meet the 95% requirement, nor lower quality such that the 95% requirement is not met.

Scenario B: Everything is the same as Scenario A except that now 2 projectors will be used. One will display an E and one will display a 3 just to the right of the E. The distance between the E and the 3 should be approximately 1/4th of a pixel width. The lens chosen should result in 95% of viewers with 20/20 vision viewing the E3 of height x off a screen and sitting at distance y being be able to identify the combination displayed as "E3" (not as "8").
Here is a crude picture I made of this in Microsoft Paint, although I didn't do a great job sizing the gaps between the pixels due to less than 100% fill ratio:



In this case the "optical resolution" is the same for scenario A and scenario B. It is only "perceived resolution" that is different. Yet the lens requirements are higher for scenario B, where enough of the small detail between the E and the 3 needs to be retained for the viewer to make out 2 separate characters, even though the E3 never went through a lens.

You could have a lens that obscures things like this image and it still might be the right lens for scenario A, but not meet the 95% requirement for scenario B due to too much light scatter into the fine black detail between the E and the 3:



I'm guessing that if Dave's expert was shown this E3 example he would agree that just looking at the "optical resolution" for one of the projectors at a time would not be enough to properly solve the problem. In my example not only could the E and 3 be shown at different times, they aren't even going through the same lens. Yet, using the "Thats because its not an optical resolution, but a perceived one" rule would get the wrong answer.

--Darin
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post #79 of 1307 Old 06-20-2017, 05:20 AM
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I knew this whole discussion reminded me of something else … and just now I remembered. In 2015, Olympus introduced a new feature in its mirrorless photo cameras, the so-called High Res Shot Mode. In this mode, the camera captures eight images in quick succession using an electronic shutter; inbetween each frame's capture, the camera makes sub-pixel adjustments to the positioning of its image sensor to let the sensor gather more information about its subject. Sounds familiar?

An intense discussion emerged in photo-centric forums wrt to the question if only very good (i.e. high-resolution) lenses could take advantage of this mode, which produces jpegs/RAWs with 40/64 MP resolution, or if it would suffice if the lens could resolve the lower 16 MP resolution of the imaging sensor itself – after all, each of the 8 frames had only this resolution and the frames were taken one after another …

Of course, Olympus mirrorless cameras have interchangable lenses, so it didn't take long to get to the empiric conclusion that indeed most lenses produced sharper pictures in high res mode than in normal mode, but the lenses known to be of better optical quality showed a clearly higher increase in sharpness than lesser lenses. In other words: the lenses needed to have a higher optical resolution to be able to capture the additional information of the in sub-pixel increments shifted sensor.

QED?
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post #80 of 1307 Old 06-20-2017, 08:29 AM
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Thanks ES. That is interesting. I would think that the better lens requirement might be weaker in that example than the one we are discussing because the camera is capturing each sub-frame individually before combining them, while in the eShift example the human brain doesn't realize that the sub-frames didn't enter the eyes at the same time, but would need to think about that some more.

As far as Dave's expert, I don't think we even need my E3 example to see their mistake. From what Dave posted of their conversation it looks like the expert took two positions that when taken together would mean they were taking a position that is so ridiculous that I don't think even anybody here took that position.

If we consider totally incoherent light with lens requirements for the following 3 cases:

A: One 2.7k image.
B: Two different 2.7k images with half pixel offset and going through the lens at different times.
C: Two different 2.7k images with half pixel offset and going through the lens at the same time.

It seems pretty clear that Dave's expert claimed A and B have the same requirements since they have the same optical resolution and just different perceived resolutions.

From what I see of the conversation this expert also took the position that with perfectly incoherent light it doesn't matter whether the 2 images go through the lens at the same time or different times, so B and C have the same requirements.

If those are really their positions, then from simple logic this expert would have to claim that A and C have the same lens requirements since if A equals B and B equals C, then A equals C.

I don't recall anybody here thinking A and C having the same lens requirements, but maybe somebody does.

Dave seems like a stand up guy who wants to get to the truth and not leave misinformation here, so I hope he will come back with updates from this expert as to whether they really believe that A and C have the same lens requirements with perfectly incoherent light, or whether they want to modify one of their other positions.

--Darin
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post #81 of 1307 Old 06-20-2017, 08:32 AM
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Just to echo Pete's point, I doubt that any of the budget units are coming close to 93 lp/mm. That is a heck of a lens. Honestly, only Projectiondesign that I know off would release the specs on their lenses.(Sim2 may have as well)The lens used on the Loki is a 66 lp/mm lens just by comparison. I have this lens on a 3k PD unit and it resolves 3k better than my Sony VW1100 resolves 4K.


Quote:
Originally Posted by Pete View Post
Here is my post from the under 3K thread which spells out what the .66 TI 4K chip requires in the way of a lens to fully resolve the images it's capable of producing :

Line pairs in optics consist of a white line followed by a black line. In terms of pixels in a row, the same concept applies...pixel on followed by pixel off. If all the rows in a panel are made the same way, vertical line pairs appear. In the case of the TI .66 DMD TRP16:9 chip, with 2716 pix per row, the needed-optical resolution is exactly 93 lp/mm. Were there 3860 pix/row in the same DMD size, a considerably higher lp/mm would be required.

The spec, then, on a lens with an MTF of 93 lp/[email protected]% for this chip would look like this:

DLP TRP 4K diag, full size.........0.67 16:10
DLP TRP 4K diag, video size......0.66 16:09
DLP TRP 4K diag. video size.......16.7640mm
Px per line......................................2716px
Number of lines.............................1528 lines
Aspect ratio..................................1.7775:1
Tot number of Px...........................4150048px
base.............................................. ..14.6111mm
height............................................ ..8.2201mm
pixel size.........................................0.005 4mm
1 line-pair size................................0.0108mm (1px on - 1px off)
Line-pairs/mm................................92.94 lp/mm (horizontal resolution)
Vertical Resolution.........................92.94 lp/mm (same as horizontal resolution)

The fact that the 4k image is comprised of two sub frames in ultra-quick succession does not reduce the lp/mm requirement of 93. You can get away with a lens that is inferior to this -- and it is probable that the bang-for-buck projectors have lenses well below the 93 range, but the picture will be progressively softer looking as the number decreases. It is disappointing that most TI partner manufactures do not list this qualitatively important lens specification.
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post #82 of 1307 Old 06-20-2017, 11:09 AM
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Originally Posted by 12GAGE View Post
Just to echo Pete's point, I doubt that any of the budget units are coming close to 93 lp/mm. That is a heck of a lens. Honestly, only Projectiondesign that I know off would release the specs on their lenses.(Sim2 may have as well)The lens used on the Loki is a 66 lp/mm lens just by comparison. I have this lens on a 3k PD unit and it resolves 3k better than my Sony VW1100 resolves 4K.
SIM2 Specifications does spell out lens resolution. Of course, their .66 4K projector is aimed at the high end of the market @ $30K.

Technical Specs:

LIGHT ENGINE and DISPLAY

DLP® Type 1-chip DMD 0.66” UHD Image resolution 4K UHD (3840x2160 pixels): 8.3M pixels Light Source and brightness(1) 450W lamp (dimmable) - up to 5.000 Ansi Lumens (in 2D mode) Lamp life expectancy(2) 3000 hours typical in ECO mode Adjustable iris 12 apertures memorized HDR capability
SIM2 Perfect Fit
Lens Super high definition pure-glass lens with telecentric optics Lens resolution 93 lines per millimeter
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post #83 of 1307 Old 06-20-2017, 01:35 PM
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Looks like I was wrong about one thing.
Quote:
Originally Posted by darinp View Post
Dave seems like a stand up guy who wants to get to the truth and not leave misinformation here, so I hope he will come back with updates from this expert as to whether they really believe that A and C have the same lens requirements with perfectly incoherent light, or whether they want to modify one of their other positions.
Looks like instead Dave has decided to claim that the disagreement was never between:
Quote:
Originally Posted by darinp View Post
B: Two different 2.7k images with half pixel offset and going through the lens at different times.
C: Two different 2.7k images with half pixel offset and going through the lens at the same time.
and that he is going to stop posting about it. Funny how some people decide to stop a conversation just as they (and their "expert" in this case) are shown to be wrong, and fortunately the posts are there to see if Dave is being truthful about what the disagreement was. He was pretty clear that he felt that since the eShift sub-frames go through the lens at different times the lens only has to resolve up to the native resolution, but if they went through at different times (which is the difference between C and B) then you would need a better lens. Here are two things Dave posted that I think made his position on that very clear:
Quote:
Originally Posted by Dave Harper View Post
If they went through at the same "time", then you'd need a better lens, just as you do with higher rez like 4K.
Quote:
Originally Posted by Dave Harper View Post
As soon as you ...

A. Flash the two native sub-frames at the same exact moment in "time"....
...
Then you must move to a higher resolution lens with greater MTF ...
He also mentioned native 4k there, but nobody was disagreeing with that. It was the changing from different times to the same time (B to C) that he clearly said would require a better lens, but then his expert said if you have totally incoherent light it doesn't matter (B and C would require the same quality of lens).

Disappointing when somebody tries to claim their position was never what it clearly was, but fortunately the posts don't lie.

--Darin
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post #84 of 1307 Old 06-20-2017, 02:41 PM
 
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Quote:
Originally Posted by darinp View Post
Looks like I was wrong about one thing.
Looks like instead Dave has decided to claim that the disagreement was never between:
and that he is going to stop posting about it. Funny how some people decide to stop a conversation just as they (and their "expert" in this case) are shown to be wrong, and fortunately the posts are there to see if Dave is being truthful about what the disagreement was. He was pretty clear that he felt that since the eShift sub-frames go through the lens at different times the lens only has to resolve up to the native resolution, but if they went through at different times (which is the difference between C and B) then you would need a better lens. Here are two things Dave posted that I think made his position on that very clear:
He also mentioned native 4k there, but nobody was disagreeing with that. It was the changing from different times to the same time (B to C) that he clearly said would require a better lens, but then his expert said if you have totally incoherent light it doesn't matter (B and C would require the same quality of lens).

Disappointing when somebody tries to claim their position was never what it clearly was, but fortunately the posts don't lie.

--Darin
This is ALL you need to know and ALL I am going to say from here on out Darin:

https://www.avsforum.com/forum/24-dig...l#post53770361

Quote:
Originally Posted by Dave Harper View Post


The original question and point was that your option C above was a native 4K panel, not two separate 2.7K panels. You just got so far into the weeds and off course that everyone gave up, including me and my "expert".
Quote:
Originally Posted by darinp View Post
Not true. Here is what you said that started the conversation this time:

Quote:
Originally Posted by Dave Harper
If this is an eShift projector, which it is, then at any given point in time there's only half the image shining through the lens, unlike true native 4K like the Sonys, which shoot all 8.3 million out of it at the same time.
Exactly Darin! In that post you quoted of mine, did I not say "...unlike true native 4K..."??? So where in there am I talking about "two native 2.7K images going through the lens at the same time???"

Quote:
Originally Posted by darinp
Then you posted:
Quote:
Originally Posted by Dave Harper
And the merging of the two sub-frames, where each goes through the lens at different points in time, happens in your eyes and brains, AFTER the lens, so what's your point?
Exactly....at "different points in time"...not the same time Darin!

I stand by my assertion that the lens only needs to resolve the native 2K or 2.7K resolution, whether the projector is eShift or not. If we are talking NATIVE 4K, then it has to be of higher quality to resolve it.

Who gives a damn about 2 separate 1080p images going through at the same time, since that isn't even a thing and not what I questioned in the first place, just as I said to you!

Quote:
Originally Posted by darinp View Post
...I really thought you would be more of a stand up guy about this.Your posts made it clear that you thought that between option B and C the C option would require more because B only required the same quality of lens as A...
I am a standup guy, and I take sincere offense that you state otherwise, and I am standing up and walking right out on this ridiculous fiasco you have created.

Quote:
Originally Posted by darinp View Post
...Since the record is here for everybody to see you really should be more honest about what position you took...
The honesty is all posted above, which shows exactly what I was saying to you.

Quote:
Originally Posted by darinp View Post
...Interesting how you decided the disagreement had gone on too long to continue just as you and your expert were shown to be wrong.

--Darin
I think you shown yourself to be the wrong one, since it clearly shows the position I took in the first post of mine you just quoted. You are the one that brought up both going through together at some point, for some unknown reason, when that isn't even a thing in eShift or native resolutions.

I have been in communication with my "expert" but he has been extremely busy. I was waiting to get full explanation on his points and your questions, although now I am just dropping this altogether and am washing my hands of this. When you yourself design super high end optics for telescopes like he is, then come back to me with your real science. Until then I am done with you.


Quote:
Originally Posted by darinp View Post
You are welcome to ignore them. I won't apologize for trying to correct misinformation from people like Dave on the AVScience forum. I don't think it is a coincidence that he decided to stop posting about it just as his expert was being proven wrong and would have trouble justifying his claims between:

A: One 2.7k image.
B: Two different 2.7k images with half pixel offset and going through the lens at different times.
C: Two different 2.7k images with half pixel offset and going through the lens at the same time.

--Darin
The only misinformation is you switching the original intent from option C above being about native 4K, to being about two separate 2 or 2.7K imaging panels going through the lens at the same time.

Quote:
Originally Posted by JackB View Post
Ditto! Go someplace else and have your discussion. I'm sick of it too.
Yes you are correct. I apologize for derailing this thread. Have a nice day everyone.
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Last edited by Dave Harper; 06-26-2017 at 09:04 PM.
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post #85 of 1307 Old 06-20-2017, 03:12 PM
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Quote:
Originally Posted by Dave Harper View Post
Exactly....at "different points in time"...not the same time Darin!
Exactly, the disagreement all along was whether it mattered that the 2 sub-frames go through the lens at "different points in time". That is what B and C is all about:

B: Two different 2.7k images with half pixel offset and going through the lens at different times.
C: Two different 2.7k images with half pixel offset and going through the lens at the same time.

Keep everything the same except for the one thing that is being disagreed on. You claim that you want proper science. Well, that is one thing in proper science. Change only one thing when you can.

Quote:
Originally Posted by Dave Harper View Post
So where in there am I talking about "two native 2.7K images going through the lens at the same time???"
This is getting hard to explain because you don't seem to even understand the basic stuff about science. When you claim:
Quote:
Originally Posted by Dave Harper View Post
If they went through at the same "time", then you'd need a better lens, just as you do with higher rez like 4K.
you are clearly saying that if they went through the same time (like example C) you would need a better lens than when they don't (like example B). Yes, you said just like higher rez like 4k, but nobody disagreed that a higher native rez requires a better lens. That was always in agreement by everybody I believe. Now you seem to want to get away from the examples with the images going through the lens at the same time even though you took a clear position on that more than once already, and we can see what position you claimed before trying to dismiss that example.

Quote:
Originally Posted by Dave Harper View Post
I am a standup guy ...
Then be that. I'm not concerned with whether you take offense given how you are now trying to claim that you never took a position that you very clearly took. If you go to your expert and ask a basic question like:
Quote:
With incoherent light, do all 3 of these require the same quality of lens:

A: One 2.7k image.
B: Two different 2.7k images with half pixel offset and going through the lens at different times.
C: Two different 2.7k images with half pixel offset and going through the lens at the same time.
And come back and post their answer even if they change their original position, then I will say you were being a stand up guy.

As long as you claim you didn't take a position between 2 eShift sub-frames going through the lens at the same time versus at different times then you will be proving me right. The posts are there that prove that even if you took other positions too.

If you were being honest you would admit that you said this:
Quote:
Originally Posted by Dave Harper View Post
As soon as you either:

A. Flash the two native sub-frames at the same exact moment in "time"....

Or

B. Use a higher resolution native imager (4K/UHD) that uses the same relatively sized surface area (.69", .74")....

Then you must move to a higher resolution lens with greater MTF
and the bolded part is related to B versus C, instead of acting like your positions were only against high native resolutions. There is clearly an "Or" in there, meaning you took both positions, so please don't act like you only took the second position and claim you are being a stand up guy as you claim not to have taken a position that you clearly took. You clearly took the position that higher native resolution requires a better lens and so did everybody else. I never disagreed with that. I disagreed with the other position that you want to act like you never took.
Quote:
Originally Posted by Dave Harper View Post
The only misinformation is you switching the original intent from option C above being about native 4K, to being about two separate 2 or 2.7K imaging panels going through the lens at the same time.
Not misinformation at all. I addressed a position you took and which there was disagreement about. If it really makes you feel better I can add an option D if you want, but everybody already agrees that D requires more than A and D versus B and C is another discussion. Resolving the things that people already agree about is not necessary. It is the relationship between A, B, and C where there was real disagreement, and where you took clear positions, even if you want to disown those claims now.

A: One 2.7k image.
B: Two different 2.7k images with half pixel offset and going through the lens at different times.
C: Two different 2.7k images with half pixel offset and going through the lens at the same time.
D. One 4k image.

--Darin

Last edited by darinp; 06-20-2017 at 03:21 PM.
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post #86 of 1307 Old 06-20-2017, 04:19 PM
 
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Quote:
Originally Posted by darinp View Post
Exactly, the disagreement all along......



--Darin
Nope, that was not the question or what I commented on "all along"! The very first post I made, which you even quoted in the UHZ65 thread, clearly shows me saying "native 4K". It was you at some point in time later that started on this E and 3 rant and whether those sub-frames go through at the same time, which I already said doesn't even apply to anything tech wise currently. eShift doesn't do it and neither does native, so why the heck does it even matter at this point. Sure I may have been so confused with all your irrelevant in the weeds babbling that I said any number of things. I never claimed to be the expert, which is why I consulted one more knowledgable who uses it on a daily basis, unlike you and I, but what I did say initially and contended with you is and was 100% correct, which Javs and Seegs seemed to both agree:

There is no option C as you're contending anyway. There is your option A and B (2 or 2.7K native panel) which use the same lens, and then option D (4K native panel, which should be C!) which then requires a higher resolution lens with fewer aberrations, which is what I first contended with you "all along" when you jumped in and starting blabbering about everything else which was never initially posted "all along" . Period and good day.
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post #87 of 1307 Old 06-20-2017, 04:41 PM
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Quote:
Originally Posted by Dave Harper View Post
Nope, that was not the question or what I commented on "all along"! The very first post I made, which you even quoted in the UHZ65 thread, clearly shows me saying "native 4K".
Your first post on this clearly said that since the 2 eShift frames go through the lens at different times they shouldn't require extra lens requirements, "unlike true native 4k". So, yes, you said "native 4k" as part of your claim that whether the eShift frames go through the lens at the same time or different times determines whether the extra resolution matters. I think it should be clear to everybody here what position you took in that post:
Quote:
Originally Posted by Dave Harper View Post
If this is an eShift projector, which it is, then at any given point in time there's only half the image shining through the lens, unlike true native 4K like the Sonys, which shoot all 8.3 million out of it at the same time.
Relative to my 4 choices of:

A: One 2.7k image.
B: Two different 2.7k images with half pixel offset and going through the lens at different times.
C: Two different 2.7k images with half pixel offset and going through the lens at the same time.
D. One 4k image.

You were clearly taking the positions that D requires a better lens than A (which everybody agrees on) and since in B the eShift frames go through the lens at different times (unlike choice C) then B doesn't require a better lens than A, unlike D (or "unlike true native 4k"). You then made it clear later that your position was that B doesn't require better lenses than A because the sub-frames don't go through the lens at the same time. That is what C is there for. Since you claimed that the reason B doesn't require more than A is because they don't go through the lens at the same time, then C is there for the case that they do. This doesn't seem like complicated English to me. When you say it doesn't require a better lens due to not going through the lens at the same time that is stating that if they did go through at the same time the answer would be different. This can be broken down simple as saying B doesn't require more than A, but C would just like D would.
Quote:
Originally Posted by Dave Harper View Post
I never claimed to be the expert, which is why I consulted one more knowledgable who uses it on a daily basis, unlike you and I, but what I did say initially and contended with you is and was 100% correct ...
Your expert said that if the light is completely incoherent then it wouldn't matter whether the eShift sub-frames go through the lens at the same time or at different times. This is different than you claimed when you said:
Quote:
Originally Posted by Dave Harper View Post
If they went through at the same "time", then you'd need a better lens, just as you do with higher rez like 4K.
,
Quote:
Originally Posted by Dave Harper View Post
There is no option C as you're contending anyway.
Then why did you comment on the reason for your claim about B not requiring more than A being because it isn't like C?

You want to bring in what you consider a scientific expert, then you want to avoid any thought experiments, even if you already took a position on them. If your expert is as good as you think then they should have no trouble at all dealing with a thought experiment. That is much of what science is about.
Quote:
Originally Posted by Dave Harper View Post
There is your option A and B (2 or 2.7K native panel) which use the same lens, and then option D (4K native panel, which should be C!) which then requires a higher resolution lens with fewer aberrations, which is what I first contended with you "all along" when you jumped in and starting blabbering about everything else which was never initially posted "all along" .
Please stop trying to make people think that your original position wasn't that B only requires the same lens as A because of the difference between B and C. It doesn't look good when the posts are there for people to see that your whole reason for claiming B doesn't require more than A is because the 2 sub-frames don't go through the lens at the same time.

If you really care about the truth please at least ask your expert whether A, B, and C require the same quality of lens with incoherent light (and include D if you want). They shouldn't have any problem with that thought experiment. They seemed to be fine with thought experiments and you seemed to be fine with the thought experiment in your texts with them until that started to go against your original position about the reason B doesn't require a special lens is because the eShift frames don't go through the lens at the same time.

You seemed fine coming here and telling everybody that your expert said you were right and that C requires a better lens than B. Why would you say that moving from flashing both eShift frames at different times to flashing them at the same time would require a higher resolution lens if that wasn't actually your position?

It certainly isn't my fault if you stated that position and didn't actually believe it. Seems rather convenient to me to start claiming that what you posted about flashing at different times versus flashing at the same time wasn't actually your position.

--Darin

Last edited by darinp; 06-20-2017 at 05:32 PM.
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post #88 of 1307 Old 06-20-2017, 05:17 PM
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BTW: If anybody besides Dave is confused about the position(s) he took, I think he made his position very clear when he was being a smart-alec to RLBURNSIDE (among other times):
Quote:
Originally Posted by Dave Harper View Post
Quote:
Originally Posted by RLBURNSIDE View Post
Interesting post. However, that doesn't really address the fact that 2.7K + XPR does require a better lens than one without XPR, if you actually want to see that extra detail, since the lens sits between the DMD + wobulator and the screen, so it's not enough to want a 2.7K lens, IMO.
And the merging of the two sub-frames, where each goes through the lens at different points in time, happens in your eyes and brains, AFTER the lens, so what's your point?
Whether he now wants to claim he never took the position or not, his position there and in other posts was clearly that if you do:

B: Two different 2.7k images with half pixel offset and going through the lens at different times.

instead of doing:

C: Two different 2.7k images with half pixel offset and going through the lens at the same time.

then you don't need a better lens than:

A: One 2.7k image.

Dave was pretty smug about that position before, but now seems to want to distance himself from it.

--Darin

Last edited by darinp; 06-20-2017 at 05:21 PM.
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post #89 of 1307 Old 06-20-2017, 06:52 PM
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Quote:
Originally Posted by Eternal_Sunshine View Post
I knew this whole discussion reminded me of something else … and just now I remembered. In 2015, Olympus introduced a new feature in its mirrorless photo cameras, the so-called High Res Shot Mode. In this mode, the camera captures eight images in quick succession using an electronic shutter; inbetween each frame's capture, the camera makes sub-pixel adjustments to the positioning of its image sensor to let the sensor gather more information about its subject. Sounds familiar?

An intense discussion emerged in photo-centric forums wrt to the question if only very good (i.e. high-resolution) lenses could take advantage of this mode, which produces jpegs/RAWs with 40/64 MP resolution, or if it would suffice if the lens could resolve the lower 16 MP resolution of the imaging sensor itself – after all, each of the 8 frames had only this resolution and the frames were taken one after another …

Of course, Olympus mirrorless cameras have interchangable lenses, so it didn't take long to get to the empiric conclusion that indeed most lenses produced sharper pictures in high res mode than in normal mode, but the lenses known to be of better optical quality showed a clearly higher increase in sharpness than lesser lenses. In other words: the lenses needed to have a higher optical resolution to be able to capture the additional information of the in sub-pixel increments shifted sensor.

QED?
Definitely QED - the key parallel here being that the hi-res image is acquired in multiple instants in time and THEN combined - from a fixed optical image coming in onto the sensor. The better the optical image coming in, the better the detail level captured. It's not like "well we're only capturing part of it in each sub-sample at a time so the lens doesn't need to be very high resolution!" That seems to be one of the propositions being put forward here for the "reverse" direction of the rays!

Better lenses allow more detail to be captured. Now play that all backwards - better lenses allow an image made up of more details to be projected better than poor lenses. Of course, if the lens causes blur at 1080pXY it will project 4k (however it is created) worse than one that projects 1080pXY with much less blur, but there will be an increase in detail either way. Whether it's the full benefit of the extra digital information will depend on a bunch of other factors. (I've spent a lot of time with 5DsR and OM-D Em1 Mk2 capturing more MP with a given lens and the more MP always provides better images even for the same lens. This is just the backwards thing)
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post #90 of 1307 Old 06-21-2017, 02:48 PM
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The misinformation from Dave and his expert has spread to yet another thread. I am responding here in the dedicated thread for this issue.
Quote:
Originally Posted by TheronB View Post
Especially since we've established, thanks to Dave Harper, that we don't need a better lens.
It is unfortunate that you have been misinformed and that this misinformation has spread to another thread on the AVScience forum. When Dave was claiming the expert had confirmed that Dave was right, he left out the part where the expert said that if you use incoherent light then passing 2 eShift sub-frames at different times has the same lens requirements as passing those 2 eShift sub-frames at the same time. I doubt anybody here is so confused that they think one native frame requires just as good a lens with incoherent light as 2 native sub-frames with 1/2 pixel offset going through the lens at the exact same time. Do you believe that? You would have to believe that to buy this expert's positions.

This is a good example of how not asking the right questions and relying on an expert's credentials, while expecting them to answer for a case they don't normally deal with, can lead to false claims. Especially if you don't know (or care) enough to ask followup questions when there are holes in their claims.

If Dave is the stand up guy he says he is he will be back with a correction from his expert, since 2 of his expert's claims can only both be true if the expert believes something that is completely ridiculous. I doubt the expert actually believes that ridiculous thing, so if asked the proper questions I expect that the expert would change one of those positions.

Hopefully Dave will provide a correction in this thread at least and then respond to his own misinformation in other threads that his expert hadn't been quite right about everything.

--Darin
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