Fudoh's ode to old display technology

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citrus3000psi
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Re: Fudoh's ode to old display technology

Post by citrus3000psi »

I used the OSSC lat tester on PDP-V402 today using a rankie VGA converter. Bottom corner resulted in 6ms.
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hyrulebr
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Re: Fudoh's ode to old display technology

Post by hyrulebr »

If someone was looking for an original Sony setup probe (BKM 14L):

https://www.ebay.com/itm/Sony-Bkm-14l-A ... ect=mobile

Hard to find... and hard to pay... :mrgreen:
Ikaruga11
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Re: Fudoh's ode to old display technology

Post by Ikaruga11 »

hyrulebr wrote:If someone was looking for an original Sony setup probe (BKM 14L):

https://www.ebay.com/itm/Sony-Bkm-14l-A ... ect=mobile

Hard to find... and hard to pay... :mrgreen:
Dang, I really could have used that. Does it work with the D-series BVMs?
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Xer Xian
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Re: Fudoh's ode to old display technology

Post by Xer Xian »

GeneraLight wrote:Dang, I really could have used that. Does it work with the D-series BVMs?
Perfect color accuracy is definitely not needed for gaming (even more so for 240p games, that may have been 'color corrected' with an NTSC Composite signal for all we know). Unless you were gonna use it to calibrate a BVM F24 for watching movies, in which case yeah that would actually be a shame.
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Re: Fudoh's ode to old display technology

Post by nissling »

Xer Xian wrote:(even more so for 240p games, that may have been 'color corrected' with an NTSC Composite signal for all we know)
What do you mean by this? All games, with colors, have been drawn with RGB. Only time composite would even be relevant is if dithering is used, which is a completely different topic than color accuracy.

Also keep in mind that most games that run in 240p have very limited color palettes. To deviate from those, when developing games, makes no sense whatsoever. Especially when you consider that the colors turns up different in NTSC and PAL when using composite video.
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Xer Xian
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Re: Fudoh's ode to old display technology

Post by Xer Xian »

nissling wrote:What do you mean by this? All games, with colors, have been drawn with RGB. Only time composite would even be relevant is if dithering is used, which is a completely different topic than color accuracy.

Also keep in mind that most games that run in 240p have very limited color palettes. To deviate from those, when developing games, makes no sense whatsoever. Especially when you consider that the colors turns up different in NTSC and PAL when using composite video.
First, I must say have zero knowledge about games development, so I actually ventured a bit further than what I should have had with that post. Still, I get that the games' visuals must have been coded digitally and have a definite color value in that context, but how does that translates once they are actually rendered by the consoles? Consoles that are probably not even able to output RGB natively, which is why nowadays we have people coming up with different palettes.. I don't know. I can't believe you need your display to hit an sRGB color chart with 99% accuracy for retrogaming, but I'm happy to be corrected if I'm wrong.
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Re: Fudoh's ode to old display technology

Post by Ikaruga11 »

Xer Xian wrote:
GeneraLight wrote:Dang, I really could have used that. Does it work with the D-series BVMs?
Perfect color accuracy is definitely not needed for gaming (even more so for 240p games, that may have been 'color corrected' with an NTSC Composite signal for all we know). Unless you were gonna use it to calibrate a BVM F24 for watching movies, in which case yeah that would actually be a shame.
Yeah, others have said that as well. But can it be used with D-series BVMs? Google results show that it'll work with the A, E and F series BVMs. But no mention of the D series.
Dochartaigh
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Re: Fudoh's ode to old display technology

Post by Dochartaigh »

GeneraLight wrote:Yeah, others have said that as well. But can it be used with D-series BVMs? Google results show that it'll work with the A, E and F series BVMs. But no mention of the D series.
It works with the BVM D-series - says so in the manual.
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Xer Xian
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Re: Fudoh's ode to old display technology

Post by Xer Xian »

So for anyone that is looking to calibrate one's BVM with a probe and could use some reference (the BKM 14L manual is not very helpful). It wasn't easy but I did find the procedure to set the white and black point that was followed by someone who seemed to be a pro calibrator: link. Here's a quote:
I have worked out this procedure after many years of calibration experience with the Sony BVM series monitors.
The procedure is the same for HD or SD. That means 23.98psf for the most HD, and some 1080i 59.94 and the usual 525 for SD.
A serial digital path and optional input cards for the above monitors is assumed.
Monitor test signals are available from many companies, the one I have used are the Evertz 7750TG2 [...]
I do not use the internal test signals for calibration, only for convergence. After configuring input, (use channel set only, do not attempt to copy from one channel to another, create a new channel for every type of standard or frame rate, SD, HD, NTSC, PAL,DI, etc. Using channel set only, means that you must manually configure and calibrate each individual channel.
Turn on brightness hold. This is important.
White field purity and convergence, sizing, for underscan / overscan, stable operating temp. (monitor stays on 24 / 7) are assumed to been achieved before color temp calibration is attempted.
For the larger HD monitor, the optional Sony probe is needed to run Digital Uniformity alignment manually across the CRT.
SD channels set for 4X3 underscan.
HD channels set for 16x9 underscan.
Apply bars to input,
Perform the automatic adjustment using AUTO menu A12 in control preset.
Apply 100 IRE window over black.
Carefully position suction cup of Philips 5639 probe over white part of test signal, Correct setup, operation and calibration of philips meter is assumed.
Use contrast / brightness control presets to set for 30 FTL on meter.
Apply 20 IRE gray window over black.
There is no published target value for black level. I use .78 FTL
Perform color temp adj, by using RGB gains for white point (100 IRE, RBG bias for black, (20 IRE gray)
Set for 6500 K using magnify function on Philips meter.
Go back and forth between white and black until target values are achieved.
30 FTL at 100 IRE white window at 6500 K
.78 FTL at 20 IRE gray window at 6500 K

Apply split bars with PLUGE
Set brightness for PLUGE, lower 2 chips to blend / disappear into other raster black, while clearly seeing the brightest chip of the 3 level PLUGE. There is some subjectiveness to setting the "black level" of the monitor by this method. Most agree pretty much, with the occasional colorist requesting the PLUGE to be set a little higher. There is always the option (and danger) of taking the monitor out of preset, (brighjtness only) for a session should the colorist desire. That creates the possiblity that the next operator might not notice. This should be the only reason why an operator would have to intervene with a calibrated monitor. Nothing else can be set by eye.
If the brightness is changed to achieve black level according to PLUGE, you must go back and forth with the 100 IRE window to maintain 30 FTL The . 78 value is discarded in favor of the value set by EYE using the PLUGE as described above. The final check should be in blue only to confirm phase and saturation are correct I'm sure everybody has their variations and little tricks. I have found that deviating from using 20 IRE or 100 IRE is not necessary. If the CRT is in good condition the black point will track down to the darkest blacks. If it does not and you are sure everything was done correctly then it's most likely an indication that the CRT should be replaced.
So it looks like even with a probe, it's not exactly a plug&play matter, if you want an optimal result. In fact, the guy above didn't even use the white test pattern built in the BVM (despite them apparently having an auto-adjustment feature - see first post in this same page of the thread), but rather an external signal generator sending out a digital signal (SDI or HD-SDI) to the BVM. Btw, I'd suggest not using an old, random console with the 240p test suite (but I'm not expert :) )
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Xer Xian
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Re: Fudoh's ode to old display technology

Post by Xer Xian »

Apologies for double posting, but after thinking some more about this matter (i.e. achieving perfect calibration), I believe that - to the benefit of our hypothetical perfectionist retrogamer - a few caveats are in order:

- First caveat is an obvious one, but worth mentioning - it's imperative that the consoles' RGB cables have the voltage level on the video lines correctly attenuated. It makes absolutely no sense to achieve perfect white and black points but then have a signal that goes out (or doesn't cover fully) the 0-100IRE analog standard. Luckily, we have RGC and RCA selling high quality cables, but still, it might be worth checking that they go exactly up to the ~0.714V analog standard. I'd say that the margin of error should be under 2IRE/0.017V for perfect range & absolutely no white crush (very tight margin there!). If, for some reason, usage of an NTSC-encoded signal is needed, the BVM might need to have the black level changed from 0 to 7.5IRE (the NTS Committee redefined absolute black from 0 to 7.5IRE in 1953, because early black-and-white transmitters couldn't manage a color signal with a 0V black level)

- Second caveat is more substantial and has to do with the BVM monitor's calibration. Having the BKM-14L probe (or compatible) and following the procedure illustrated in the previous post will ensure perfect white and black level (provided that the monitor is functioning perfectly). That should allow for the reproduction of a neutral gray scale and accurate colors. If that's not the case, then there are calibration issues that cannot be resolved through white and black balance adjustment alone - for example, it might be possible that the gamma response of the monitor has changed (see here for how to build a makeshift photometer for testing.. unfortunately Sony did not declare the native gamma response of their monitors, and I was only able to find measurement of the transfer curve of the Sony FW900 VGA monitor.. see pdf here, paragraph II.6 'Bit Depth'). Since there's no built-in gamma correction system on BVM's, for the necessary adjustments it will be needed to route the consoles' output into a video processor that has an advanced parametric gamma and color management system. Lumagen VPs are well regarded in this aspect (see Lumagen's Tech Tip pdf on the matter here), but they absolutely need to be paired with the OSSC for line multiplying and scanlines addition (since they forcibly subsample all signals to 4:2:2 and can't output 240p). Of course, the Lumagen will have to support analog RGB inputs and outputs (SDI output would be better, but I am not aware of any that are equipped with it)

- Last caveat is that even if BVM's are known to be quite stable, they will still drift if left to themselves. So recalibration should be performed periodically, according to one's sensibility.
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Einzelherz
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Re: Fudoh's ode to old display technology

Post by Einzelherz »

I guess it's time for my annual post titled "just buy a colorimeter and spend an afternoon learning to calibrate" followed by "and then calibrate every screen you and your family own".
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DoomsDave
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Re: Fudoh's ode to old display technology

Post by DoomsDave »

Does anyone know if you can switch between RGB and Component on a PVM 20L5 by pressing buttons on the front panel instead of going into the menu?
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Einzelherz
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Re: Fudoh's ode to old display technology

Post by Einzelherz »

Only if you have an RGB add in board. That the JVCs keep it on a separate channel appears to be an oddity. I suspect that's because a studio or whoever would probably never need to change it once it's setup.
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DoomsDave
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Re: Fudoh's ode to old display technology

Post by DoomsDave »

Yeah that makes sense, thanks. I saw a vid with someone doing it on 9" PVM and thought it was worth asking anyway.
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Lawfer
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Re: Fudoh's ode to old display technology

Post by Lawfer »

dave_20ps1 wrote:Hey guys, bit embarrassed to be posting a request for help as my first post but hey oh here we go.

I'm trying to connect my Megadrive 1 to a sony kx-20ps1 using an rgb scart cable bought from retro gaming cables in the UK.

I can get a stable picture but it's not sharp and the colours are either blown out or just incorrect.

Here's a sample of what I am getting - the path should be grey & the colours on the hills are blown out & blocky.

Image

I tracked down a block diagram of the scart input just to confirm that it would accept rgb.

Image

Image

Can anyone see anything non-standard with this that might cause the problems illustrated above.

Any help would be hugely appreciated.

Cheers, Dave.
I have the same monitor as you have and have never been able to get a proper RGB picture with it, only composite seem to work properly. I have basically almost tried everything, RGB Scart from multiple Consoles PAL, NTSC, CSYNC, Composite Video as Sync and Official Cables, Retro Gaming Cables and even got a 34 Pin adapater for the RGB Multi Input connector (the one below the Scart input), nothing works and if it does work I get the exact same messed up picture with incorrect colors as you did. The only thing I haven't tried yet is the RGB DIN Multi Connector, but I doubt it would work either.
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werk91
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Re: Fudoh's ode to old display technology

Post by werk91 »

Awhile back I was considering picking up that same Sony screen and after some research it seemed that it just doesn't support RGB at all. Despite the Scart port... :?
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Fudoh
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Re: Fudoh's ode to old display technology

Post by Fudoh »

Doesn't Rob on Youtube have a video which shows the Sony 20" Profeel running with both composite and RGB (while demonstrating the differences) ?
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Re: Fudoh's ode to old display technology

Post by svensonson »

Fudoh wrote:Doesn't Rob on Youtube have a video which shows the Sony 20" Profeel running with both composite and RGB (while demonstrating the differences) ?
right, saw this as well. He also said that his set came with what he thinks is a jp21 to euro scart adapter. not sure if he used this adapter to hook up his mega drive rgb into it. he was testing it with composite video before. maybe the scart is jp21 type
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Re: Fudoh's ode to old display technology

Post by gavme »

Blair wrote:Had some fun the other day testing a new phone camera and playing with the game-boy interface (component/YUV) on my pvm-14m2u.
Looks awesome. I've recently put together a guide on running the GBI off a standard GameCube memory card which some people might find useful.

https://youtu.be/cdvY1vx5vMo
Ikaruga11
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Re: Fudoh's ode to old display technology

Post by Ikaruga11 »

What do I use I if want to hook up multiple consoles (HDMI, RGB, YPbPr) to a BVM through BNC?
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Xer Xian
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Re: Fudoh's ode to old display technology

Post by Xer Xian »

GeneraLight wrote:What do I use I if want to hook up multiple consoles (HDMI, RGB, YPbPr) to a BVM through BNC?
A switcher that accepts RGB and YPbPr, or two dedicated switchers with a BNC T-connector to same input. Hdmi will have to be converted to analog.

By the way, there's another BKM-14L probe currently up for sale on eBay: https://www.ebay.com/itm/SONY-BKM-14L-S ... 3001143971
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Re: Fudoh's ode to old display technology

Post by Steamflogger Boss »

Xer Xian wrote:
GeneraLight wrote:What do I use I if want to hook up multiple consoles (HDMI, RGB, YPbPr) to a BVM through BNC?
A switcher that accepts RGB and YPbPr, or two dedicated switchers with a BNC T-connector to same input. Hdmi will have to be converted to analog.

By the way, there's another BKM-14L probe currently up for sale on eBay: https://www.ebay.com/itm/SONY-BKM-14L-S ... 3001143971
Those Extron matrices do it all, they are big and bulky though.
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Re: Fudoh's ode to old display technology

Post by cybermat »

Hello,
i own a Sony BVM 20F1E and i'm trying to set up the following configuration

Raspberry PI3 -> VGA GERT 666 -> EXTRON RGB 192V -> BVM 20F1E

Anyone of you could tell me the best HDMI_TIMINGS for this kind of setup ? I'm writing here because the HDMI TIMINGS found in the web (retrorgb and a lot of other sites) seems to give some troubles.
If i use the same HDMI_TIMINGS with and w/o EXTRON, i have 2 different output results.

I bought EXTRON in order to use CSYNC on BVM, because i tried with a T (shame on me i know) and i had what we call flickering or similar, but in theory at 240P i should not have flickering...right?
Using EXTRON i have the same "flicker" issue. I tried with sync on green and with Csync , used different BNC cables...same result.

I tried different HDMI_TIMINGS at 240P, someone is better than other and i tried different Sony BVM (yes i know i'm lucky).


Maybe is normal having also at 240P, that kind of trembling at the edges of the screen? It's annoying, i thought that with a good sync signal i should get rid off this issue.
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Syntax
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Re: Fudoh's ode to old display technology

Post by Syntax »

I see alot of BVM owners doimg this but why are you guys compelled to get a top $ broadcast crt and stick a laggy pi3 up its bum?

Its like living in a Lamborghini....
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ChuChu Flamingo
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Re: Fudoh's ode to old display technology

Post by ChuChu Flamingo »

Syntax wrote:I see alot of BVM owners doimg this but why are you guys compelled to get a top $ broadcast crt and stick a laggy pi3 up its bum?

Its like living in a Lamborghini....
Same reason people put Pandora boxes/PIs on Candy Cabinets, it jest werks.
cybermat
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Re: Fudoh's ode to old display technology

Post by cybermat »

Sony BVM is free of charge! I had Pi3 and i bought 7$ VGA Video card and 20$ of Extron RGB syncer :)
I know that this forum is not focused on emulation, about lag and so on, but there a lot of gamers with this CRT that could have experienced this.

Anyway now that i own this CRT i'm looking for real consoles to plug in :)
svensonson
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Re: Fudoh's ode to old display technology

Post by svensonson »

Finally got my hands on an OSSC to test it on one of my Sony FW900 Monitors. Never thought that I would really need an OSSC tbh. First I had some really bad noise using 5x line mode before I upgraded it to the latest offical 0.79 Firmware. Now its output is really impressing.

Setup:
OSSC 5x line mode 1200p>HDFury1>FW900

https://imgur.com/a/I8ukd

The Zelda picture was taken before I tweaked the setings on both the ossc and monitor itself
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Re: Fudoh's ode to old display technology

Post by kazaakas@hotmail.com »

LDigital wrote:
AndehX wrote:Actually, this reminds me. I have an odd issue with my BVM. The linearity seems to be warped in a certain part of the screen. Here is an extremely exaggerated example of what I mean:

Image

Now obviously mine isnt anywhere near that bad, it's hardly noticable on stil images, but when im playing a game that scrolls, like Link to the Past for example, you can quite easily notice the warping of the image in that area of the screen.

Is that fixable? and if so how?
This is something that I haven't seen discussed enough but I hate to say this is the reason I have owned and sold so many bvms of the 20+ variety.
It is pretty much on every one I have owned and is common and consistent enough to make me think that it's universal to the design of the tube or deflection. admittedly I have not changed any caps for this issue but I have swapped multiple boards of different ages with different units and this always persists.

It's almost always in that spot of the screen you pointed out but it is much less exaggerated. The problem is that once I see it I can't unsee it.

I have spent days and days tinkering with linearity to try and sort this but because it's an isolated slice of the screen it can't really be isolated and controlled

If you want to check for it try looking at the background gate of super castlevania 4 in stage 1-2 to watch the rails slightly compress and then release as you walk by. Another good one is the checkered pattern of green hill zone while moving slowly left and right. My advice for anyone with a bvm with a smidgen of OCD is to not look out for it in the first place.

The ONLY Sony monitor that I have that has absolutely no evidence of this issue is the BVM2011p which I can honestly say has perfect geometry in comparison to my other types but has its own quirks (no tilt control for gravity compensation and contrast bloom)
I picked up several BVM-20F1E's with ~15k hours on them and they all have this issue in that very part of the screen as well. Honestly I was really baffled to see the location of the screen being displayed here so accurately. I was afraid that the yoke was slightly displaced due to transport, but since all of mine have this problem and yours too, it must be a production error. Since these monitors were aimed at professional color applications for the film industry, I can understand why Sony got away with it. You really don't notice it unless playing any sort of side scrolling game. I was playing myself some 3D PS2 games and had 0 problems with it, but 10 seconds of playing a platformer and it's very noticable. From what I've seen the D24 and D32 have insanely good geometry and linearity in comparison. I can't even get a perfectly square picture with an underscanned game and from what I've seen from photos the D24 had fixed-pixel-like geometry and linearity.
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Re: Fudoh's ode to old display technology

Post by fernan1234 »

kazaakas@hotmail.com wrote:
LDigital wrote:
AndehX wrote:Actually, this reminds me. I have an odd issue with my BVM. The linearity seems to be warped in a certain part of the screen. Here is an extremely exaggerated example of what I mean:

Image

Now obviously mine isnt anywhere near that bad, it's hardly noticable on stil images, but when im playing a game that scrolls, like Link to the Past for example, you can quite easily notice the warping of the image in that area of the screen.

Is that fixable? and if so how?
This is something that I haven't seen discussed enough but I hate to say this is the reason I have owned and sold so many bvms of the 20+ variety.
It is pretty much on every one I have owned and is common and consistent enough to make me think that it's universal to the design of the tube or deflection. admittedly I have not changed any caps for this issue but I have swapped multiple boards of different ages with different units and this always persists.

It's almost always in that spot of the screen you pointed out but it is much less exaggerated. The problem is that once I see it I can't unsee it.

I have spent days and days tinkering with linearity to try and sort this but because it's an isolated slice of the screen it can't really be isolated and controlled

If you want to check for it try looking at the background gate of super castlevania 4 in stage 1-2 to watch the rails slightly compress and then release as you walk by. Another good one is the checkered pattern of green hill zone while moving slowly left and right. My advice for anyone with a bvm with a smidgen of OCD is to not look out for it in the first place.

The ONLY Sony monitor that I have that has absolutely no evidence of this issue is the BVM2011p which I can honestly say has perfect geometry in comparison to my other types but has its own quirks (no tilt control for gravity compensation and contrast bloom)
I picked up several BVM-20F1E's with ~15k hours on them and they all have this issue in that very part of the screen as well. Honestly I was really baffled to see the location of the screen being displayed here so accurately. I was afraid that the yoke was slightly displaced due to transport, but since all of mine have this problem and yours too, it must be a production error. Since these monitors were aimed at professional color applications for the film industry, I can understand why Sony got away with it. You really don't notice it unless playing any sort of side scrolling game. I was playing myself some 3D PS2 games and had 0 problems with it, but 10 seconds of playing a platformer and it's very noticable. From what I've seen the D24 and D32 have insanely good geometry and linearity in comparison. I can't even get a perfectly square picture with an underscanned game and from what I've seen from photos the D24 had fixed-pixel-like geometry and linearity.

I noticed this too in my D20F1U soon after I started using it. It bothered me a bit at first but it didn't take long for me to learn to ignore it most of the time. The great performance of this monitor in so many other regards makes this an acceptable trade-off IMO. The D24 has its own trade-off, with what is in most accounts perfect geometry at the cost of a noticeable smaller 4:3 image (though I imagine also a bit sharper than the 20F1s, with 100 more lines AND being smaller).
The D32 is probably the best of all possible worlds, though it too has its trade-offs (especially its insane cost and insane weight).
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Re: Fudoh's ode to old display technology

Post by Sefirosu789 »

fernan1234 wrote:
kazaakas@hotmail.com wrote:
LDigital wrote:Actually, this reminds me. I have an odd issue with my BVM. The linearity seems to be warped in a certain part of the screen. Here is an extremely exaggerated example of what I mean:

Image

Now obviously mine isnt anywhere near that bad, it's hardly noticable on stil images, but when im playing a game that scrolls, like Link to the Past for example, you can quite easily notice the warping of the image in that area of the screen.

Is that fixable? and if so how?
This is something that I haven't seen discussed enough but I hate to say this is the reason I have owned and sold so many bvms of the 20+ variety.
It is pretty much on every one I have owned and is common and consistent enough to make me think that it's universal to the design of the tube or deflection. admittedly I have not changed any caps for this issue but I have swapped multiple boards of different ages with different units and this always persists.

It's almost always in that spot of the screen you pointed out but it is much less exaggerated. The problem is that once I see it I can't unsee it.

I have spent days and days tinkering with linearity to try and sort this but because it's an isolated slice of the screen it can't really be isolated and controlled

If you want to check for it try looking at the background gate of super castlevania 4 in stage 1-2 to watch the rails slightly compress and then release as you walk by. Another good one is the checkered pattern of green hill zone while moving slowly left and right. My advice for anyone with a bvm with a smidgen of OCD is to not look out for it in the first place.

The ONLY Sony monitor that I have that has absolutely no evidence of this issue is the BVM2011p which I can honestly say has perfect geometry in comparison to my other types but has its own quirks (no tilt control for gravity compensation and contrast bloom)
I noticed this too in my D20F1U soon after I started using it. It bothered me a bit at first but it didn't take long for me to learn to ignore it most of the time. The great performance of this monitor in so many other regards makes this an acceptable trade-off IMO. The D24 has its own trade-off, with what is in most accounts perfect geometry at the cost of a noticeable smaller 4:3 image (though I imagine also a bit sharper than the 20F1s, with 100 more lines AND being smaller).
The D32 is probably the best of all possible worlds, though it too has its trade-offs (especially its insane cost and insane weight).
My JVC DT-V1910 also has this issue, however my D24 does not. I was told that only the D20, D24 and D32 are able to fix these horizontal linearity issues in the service menus:

Image
Image
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