TVONE Blending Info, General Q&A or just how to? - Page 24

Well finally got the Longbows up on the ceiling !! I did a preliminary set up and have some issues with convergence on the lower left corner of the right PJ. I just can not get it to converge with the left PJ at that spot no matter what geometry controls i use to manipulate it. This might be a bad convergence coil that Scott was talking about making their way into a few Pj's. I worked on Schemflug and on my set up had to use the protected factory adjustors to get it right. i have gotten pretty good doing this now!

I took some shots of twilight and just now noticed on this rig that it was shot with lots of film grain, i never noticed it on my M8000. but this set up shows all that detail, and I thought it was just a poor transfer. here are the shots, I still have not touched the colorimetry in the blend zone as i want to get alignment done perfectly first.














nashou

Well, After confirming this with Andy in England, I have found an issue with these units that I hope Tv-One will look into. in the blend zone there is a bit depth issue as andy calls it. The blend S-curve is generated from an 8-bit look-up table and it should be a 24 bit to get perfect blend zone , the 8 bit leaves vertical lines on bright scene's here is an 70IRE full field where you can see what i am talking about, it also leave bright bars towards the center of the image. Andy said those can be worked out by contrast modulation which i have not tweaked yet.


Zoom in of vertical lines both PJ's on( disregard non matching colors, i have not tweaked it yet )



bright bars near center and vertical lines in blend zone



Blend Off no Vertical lines(one pj on)



Blend on one PJ vertical lines visible



I am in contact with Tv-One and I hope they are able to resolve this. Lets see what they come up with.

Bob did you notice this at all? Andy and I both confirmed it but he's having some home issues an has been busy with that to post his findings here.

Athanasios

Athanasios,

Yes - I have noticed exactly the same thing. Hopefully they can fix it, and when they do they can add 21 pt. control at the same time!

BTW - What blend zone gamma values did you end up with?


Bob

Dear Anthansios;

The Diventix-8022 does not have the issue of vertical lines in the blend zone. Ken Whitcomb was able to confirm (last Tuesday evening, during final calibration) my engineering hunch that 1) perfectly matched blend zone geometry, and 2) perfectly matched gray scale calibration, results in no blend zone in any scene.

The "piece de resistance" was the use of color correction boards in both projectors. These allow 18 zones per projector (3 rows by 6 zones per row) of both intensity and color (RGB drive and G2 per zone) adjustment. Ken matched the color in the 3 right most zones of the left projector to the 3 left most zones of the right projector. No color distortion in the blend zone.

Finally, Ken also used the 3 left most zones in the left projector to remove a "red push" in the left side of the left projector. Result, video nirvana.

This weekend, I am going to perform a 32 zone Audyssey Pro audio calibration to create room equalization filters for the Denon AVP-A1HDCI audio processor, to bring the audio side up to the standards of the video side. The Denon can decode a 9.3 setup, which I have Going clockwise, starting from the front left channel, I have set up: Front Left, Front Left Sub, Front Center, Front Right Sub, Front Right, Right Side Front, Right Side Rear, Right Rear, Rear LFE Sub, Left Rear, Left Side Rear, Left Side Front.

By Sunday, I will be loving life.

William

I hope they get on it too, I don't see why they can not just increase the bit depth of the lookup tables. It should be an easy fix to add more "sweep" or steps to the blend zone. I guess our CRT's are more revealing than Digital's after all!

I still am playing with it but it was lower than yours i had .15 at one point but i know this will change as i nail down the greyscale on both Pj's.


Hi William, I never noticed it before because i always thought it was the lack of precise geometry and color matching, but after i got my geometry almost perfect and was tweaking the contrast zones I noticed the lines during that process. I has the zone off for the zone adjustments then I turned it on and the lines appeared, I alway had both PJ's on when i had the edge blend engaged. Its more noticeable with one PJ off, then once I saw it i could not ignore it. it's driving me nuts!!!.

Sounds like your system is coming right along. Wish i could see how the tv-ones would perform on an opitamly set up rig, and if the lines would be less pronounced or more pronounced. I thin more , because as I kept getting closer and closer to better geometry in the blend zone it showed its ugly head!

Athanasios

William - I can agree with this. The closer I get to perfectly matched sides, the more the blend zone disappears. It is now invisible about 99.9% of the time and when it is visible, it is minor. My problem is that I'm not good enough to get them exactly matched without the help of multipoint adjustments!


Wow - I wish my pair of XGLC's had this feature - I never noticed the difference in output in different parts of the screen until doing a blend.


After seeing a blend, I think you know the answer to that as well as anyone.



William - Are these extra channels derived from the 7.1 signal?


Thanks,
Bob

this is off topic Bob but while i have your attention,Ever start work on that wall wart remover? I still want to build one or two. Let me know when you want to start that project so I can chip in for getting PCB's made up.
I want to start using the eagle PCB software again and draw up the boards, if you can draw up your version of the schematics I can give a shot at the PCB layout.

And what do think about Black Gate caps? I have a bunch to re cap my Marquee's power supplies with.

Athanasios

Short answer: yes, from a 5.1 audio stream.

Longer answer, the left sub signal comes from the full bandwidth left front channel. The right sub signal comes from the full bandwidth right front channel. My side speakers are dipoles: 2 speakers point towards the front and 2 towards the rear of the Home Theater. The right side signal is dervied from the right front and right rear channels. Same for the left side. The LFE sub, of course, gets the full LFE signal.

The Denon AVP-A1HDCI is the bees knees of audio processors. As an example, it will alow me to hook up my 3 subs 4 different ways. I am using the L/R/LFE mode. It has various other mixes available.

William

Already Here: RODAN-O-Blend's Nemisis: Blendzilla

BTW, for the record, the official arrival date of RODAN-O-Blend's nemisis Blendzilla is Tuesday, October 20, 2009, at about 9:00 PM. It will be commemorated in the history books.

yeah yeah yeah, you have Professionals helping you set up the blend, do it on your own buddy

Athanasios

William... which boards are these? Do you have a part number?

I've been using the contrast modulation boards, but they only allow for 9 zones per projector and you can only adjust drive.

Sorry - I have not forgotten - Just been busy. I should have time this winter, so I'll send you an e-mail of parameters to see what you think before I start it.



Been a while since I used any, but I remember being impressed with them.


Gino - I can't wait until you are back up and running as I would like to hear what you think of the differences between 'Zilla and "Rodan...". I think the ability to select custom output resolutions and refresh rates is a huge advantage that really suits well with our analog projectors.

Thanks,
Bob

Thats what william meant he just did the numbers for two pjs, so its 3 horizontal rows by 6 vertical rows.

Athanasios

Well after a ton of E-mails back and forth between Tv-one help desk and me and Andy and Bob , they are going to look into it more closely. They said that they have been swamped but will soon be able to move this up the list . Lets hope its a simple Firmware fix! I might try to go back a firmware to see if it is on the older one as well, you never know. Bob Are you running the latest?

Athanasios

No - I'm still running the original, as I am waiting for multipoint controls.

Somewhere in all the communications with Rob he mentioned that he now had the resources to get this accomplished. Have you heard otherwise since then?

Bob

Bob or anyone else who noticed the lines do this experiment, while using the RGBHV outs and with one PJ on and the Blend function on, go to the windows menu and then to Fade and adjust it and watch the lines, see how they move wider or narrower depending on the amount of fade, this plays into Bobs theory that its a gamma issue possibly but also it could be something else also.

It is definitely a scaling issue. I am sure after investigating it they come up with a solution. It is definitely not hardware as the fade with the edge blend function off does not cause any weird anomalies.

nashou

Athanasios = Wish I could do this, but my hardware is located two floors below my HT. It has been a pita during setup, but I have got good exercise climbing up and down two flights of stairs!

Bob

Connect a scope to the output of the unit (use the green out for this). Externally trigger the scope using the 'VERTICAL' sync from the unit.

Inject a full white field into the units input.

Setup the scope displaying and showing the blend roll-off at either the right or left of the scopes screen (depending on which out you're using).

Evaluate that roll-off as you adjust the blend zone or gamma. It should show a VERY smooth slope that raises and lowers without edges or breaking.

If the slope shows any degree of distortion, you could at that point consider the unit used for blending, as NOT being a blend unit.

Thanks Mike, I'll give it a try, its a dvi out via an RGBHV breakout cable, i wonder if the length of the cable might have something to do with it.
can I use BNC "T" fittings on the Green and V sync to send to the scope?
How do i "Externally trigger the scope using the 'VERTICAL' sync from the unit." Do i connect two probes to one input on the scope using a BNC "T fitting"? Also I added the other Moome card back in and the lines are much less pronounced, very muted but still there. So it seems to be more of an issue with RGBHV outs.

The thing that is weird is if I adjust the blend zone size i do not see the lines do anything strange like jump quickly to the new position they just move very smooth with the blend edge. its when I use a fade function on the unit that will fade to black the entire image, the lines move and jump quickly to a new position with in the blend zone and there are wider bars that do the same with in the main part of the image. That could be a non linear fade function causing that and has nothing to do with the blend curve.

But I'll try the scope once i get a chance, brother in-laws birthday tonight.

Athanasios

Thats easy to do, set your camera to record video, hit record, run tot he control room and adjust the the fade up and down then go back and check !


Nashou!!!!!!

That's what I thought initially but he did say "These allow 18 zones per projector"

Good idea, but believe it or not, I am an analog old fart that doesn't even own a digital camera!

Mike Parkers idea of scoping the blend curve is super. If you do it, it would be interesting to see what happens to the shape as you change the gamma adjustment, especially at different IRE levels.

Based on what we are seeing, there should be "sections" of the curve that level out and then take a jump instead of a smooth exponential curve.

Bob

Good news guys, Robert is now on this one! he is Tv_OneEngineer on AVS and the one i feel knows more about the blend features of these units than anyone else there. I will still try Mikes suggestion but i got this responce when I checked my E-mails this morning:


I did try what he suggested before and IIRC it was less noticeable with a smaller blend zone. I will give it his suggestion tonight when i get home from work along with a shot at scoping. I assume I should hook the Vsync the the external triger BNC on the scope ? This way i'll start with a small blend zone , maybe 100 and increase it to see what happens.

I like his comment about CRT's

Athanasios

ok

Try and use BNC "T" connectors right at the projector.

The scope procedure is the best way to see what the blend ramp actually looks like in the electronic world.

That ramp (slope) would have to be smooth, clean and free of jaggies or any other distortion in order to perform proper blending.

Ok now I know why Rob, wanted me to raise the blend zone to 255. While I hooked up the scope and adjusted the Blend zone to increase at the 250 pixel mark it snapped down if i went lower towards 250 it snapped up. the gamma adjustment seamed normal to me, I'll let mike look at the video I am uploading to my mobileMe Web gallery.

Athanasios

Ok here is the scope video, i lowered the intensity of the beam thats why when the curve goes vertical you wont see the line but its there, hard to capture video of the scope trace with a point and shoot camera, thats why the line is fuzzy, but in reality its sharp.

http://gallery.me.com/nashou.66#1001...or=black&sel=0


let the video load before hitting play or it will stop then play.

Athanasios

I'm sorry, but you lost me. What do you mean by it snapped up and down?

Bob

bob if you watch the video the blend curve will move uo or down as i pass the 250 mark on the blend zone adjustment for size. there must be something in the algorithm they use.

Athanasios

The video won't play for me..

Anyway, Im not understanding what you're saying when you mentioned "snapped" or "moved" in your comments.

When adjusting the blend zone, the ramp (slope) should move as you make the adjustment. It should be moving very smoothly up or down, duplicating what you're doing with the blend adjustment - ONLY!

Again, any distortions (breaking, jerks, zig-zags, ripples, bends, twists, smears, etc) should not be seen.

The quality of the blender depends on how well that slope moves and transitions to the blend adjustment without distortions.