Project CRT (aka The CRT Project)

[pipefan413]

I haven't really watched many of my LDs on CRT yet (mostly been capturing and editing / syncing audio and so forth) but I noticed that THE EVIL DEAD looked decidedly yellowish a lot of the time on one of my two CRTs. Neither of the ones I have are particularly fancy, they're pretty boring, except that they both have NTSC playback, which is not that easy to find in the UK. (So run off UK 60 Hz mains but can do both 50i and 60i playback, I mean.) I think I paid about 20 quid for one of them and more or less got the other for free, so I'm not really complaining!

I dunno if that's because of age, because of it being a pretty basic telly, or because it isn't quite right for NTSC playback due to it being manufactured primarily to function with PAL broadcast TV/video. Quite possibly a combination of all of the above.

[bronan]

That is why it earned the moniker Never Twice the Same Color Not sure if anyone here is a video game fan, but one place this has received a lot of scrutiny is the original NES. It's unique among consoles in that it generates its colors in YIQ space rather than RGB. The major dispute is that a lot of people remember the sky in Super Mario Bros being more purple, while others swore it was light blue. It turned out the it wasn't faulty memories, but instead the NTSC decoder inside Sony TV treating the colors very differently compared to other manufacturers.

https://i.imgur.com/cYQpCaN.png

[PDB]

What I don't understand is why the profiles for CRTs will not in any way influence colors. A proper ICC profile should incorporate such things in my eyes.

I suppose it could be a case of "compensating for consumer equipment", but you'd still expect the profile for consumer monitors to incorporate that. Hmmm.

Well we are searching for the same answers to a long-standing theory but coming about it in different but equally valid ways. You go scientific, I'm going base observational

I think we can agree at a minimum that there is a strange pattern here, regardless of the cause. Limiting the discussion to HD masters (no DVDs, LDs), it does appear the many masters do have a red/magenta tint around the turn of the century. Once you start to look for it you can see it everywhere. A good example where to look is any MGM HD master. They scanned their entire library in the early 2000s in 2k and nearly all but not all have that red look. At that point everything was master on a CRT.

Once MGM started 4K re-scans on their big movies that look disappears. And that seems to be a consistent pattern with most studios. That their red looking masters slowly disappear in the mid 2000s. A fact that coincides with the rise of using LCD mastering panels in 2005-2008. When BDs started coming out, using CRTs for mastering started going by the wayside.

Out of curiosity, I'm trying to find the more technical aspect on my monitor for you Tom. It looks like its is spec-ed to SMPTE 240M (it seems a predecessor of Rec709 and sRGB) at D65 or D93 for 1125i or 1080i via component or RGB. I guess I can do MUSE on this . The colorspace should be roughly the same as the more modern 709. Meaning it should give off the same color image (assuming phosphor age, calibration, etc) as a generic flat panel HD TV; but it doesn't. It is definitely biased green with a little yellow and blue and so were that other examples I have seen. So the mystery continues.

I will say that watching a more modern master on the CRT looks bad as without the red bias, it is way too green. So at least the pattern is consistent in that regard. I have gotten into the service menu and can create a user profile by adjusting RGB levels and bias. So in theory I can use the default for old masters and a custom user profile for modern ones. Its a thought.

[pipefan413]

That is why it earned the moniker Never Twice the Same Color Not sure if anyone here is a video game fan, but one place this has received a lot of scrutiny is the original NES. It's unique among consoles in that it generates its colors in YIQ space rather than RGB. The major dispute is that a lot of people remember the sky in Super Mario Bros being more purple, while others swore it was light blue. It turned out the it wasn't faulty memories, but instead the NTSC decoder inside Sony TV treating the colors very differently compared to other manufacturers.

https://i.imgur.com/cYQpCaN.png

The reason I own *any* CRTs (and indeed the reason I own 2) is games. I used to mod consoles, I've got more Super Famicoms and Mega Drives (and even Mega CDs) than any reasonable human should...

I want to run Evil Dead on my other CRT to see how different it looks but I also don't want to carry a LaserDisc player through to the living room right now because knowing my luck lately, I'd probably trip and break the damn thing somehow.

What I don't understand is why the profiles for CRTs will not in any way influence colors. A proper ICC profile should incorporate such things in my eyes.

I suppose it could be a case of "compensating for consumer equipment", but you'd still expect the profile for consumer monitors to incorporate that. Hmmm.

Well we are searching for the same answers to a long-standing theory but coming about it in different but equally valid ways. You go scientific, I'm going base observational

I think we can agree at a minimum that there is a strange pattern here, regardless of the cause. Limiting the discussion to HD masters (no DVDs, LDs), it does appear the many masters do have a red/magenta tint around the turn of the century. Once you start to look for it you can see it everywhere. A good example where to look is any MGM HD master. They scanned their entire library in the early 2000s in 2k and nearly all but not all have that red look. At that point everything was master on a CRT.

Once MGM started 4K re-scans on their big movies that look disappears. And that seems to be a consistent pattern with most studios. That their red looking masters slowly disappear in the mid 2000s. A fact that coincides with the rise of using LCD mastering panels in 2005-2008. When BDs started coming out, using CRTs for mastering started going by the wayside.

Out of curiosity, I'm trying to find the more technical aspect on my monitor for you Tom. It looks like its is spec-ed to SMPTE 240M (it seems a predecessor of Rec709 and sRGB) at D65 or D93 for 1125i or 1080i via component or RGB. I guess I can do MUSE on this .  The colorspace should be roughly the same as the more modern 709. Meaning it should give off the same color image (assuming phosphor age, calibration, etc) as a generic flat panel HD TV; but it doesn't. It is definitely biased green with a little yellow and blue and so were that other examples I have seen. So the mystery continues.

I will say that watching a more modern master on the CRT looks bad as without the red bias, it is way too green. So at least the pattern is consistent in that regard. I have gotten into the service menu and can create a user profile by adjusting RGB levels and bias. So in theory I can use the default for old masters and a custom user profile for modern ones. Its a thought.

This is in line with stuff I've looked at lately as well. Although, to be honest, I feel like there's often a green push on stuff that's so extreme it really doesn't matter if you're looking at it on a CRT or a monitor or a projector or whatever. It's an irritating thing that seems to be relatively common, a bit like how once upon a time somebody decided that everything needs to be orange and teal. I've been working on the Talking Heads concert film STOP MAKING SENSE for instance and it has a ridiculously intense green push on the Blu-ray that isn't on the DVD (which I think is from the exact same film source) or on the LaserDisc (which probably isn't from that source). I've seen it on loads of (non-concert) films as well though.

[PDB]

STOP MAKING SENSE for instance and it has a ridiculously intense green push on the Blu-ray that isn't on the DVD

Ironic

[pipefan413]

STOP MAKING SENSE for instance and it has a ridiculously intense green push on the Blu-ray that isn't on the DVD

Ironic

Right?!

So here I am buying multiple copies of a LaserDisc for a band I don't even like all that much just because the HD release isn't really good enough and it annoys the hell out of me... I'm tempted to try out TOOT for this but I have a recollection of reading that it takes a ridiculous amount of time to compute, unless I'm thinking of something different.

Anyway. Ahem. I shall stop derailing.

[spoRv]

Yesterday was reading about a projector that has one image mode where white point is D55 instead of D65, to show properly old B&W movies; I guess if the white point could be related to this debate; also, would be curious to know about PAL colors...

OT: TOOT using three copies of the same edition would take "only" three times the single capture; TOOTing (or median, or average, or a mix of these techniques) will take very few time, apart initial temporal alignment.

[PDB]

That’s technically correct. Back and white films have a different color temperature.

[deleted user]

Tried to go down the SMPTE 240M rabbit hole, but sadly it was not very rewarding. I looked up the standard, entered the primaries in Photoshop, but didn't see much of a change.

So I'm wondering just how closely that monitor (if at all?) adheres to that spec. Of course it's possible I did something wrong, but I'm just reporting my half baked theories here.

Then I found this paper: https://onlinelibrary.wiley.com/doi/abs/...5080150306

It has a little diagram in it with some listed primaries without really giving much detail about where those are from, whether they are measured or from spec sheets or whatever. I first tried the "NTSC" one but it just made the image more colorful. Then I tried Matsushita, but that wasn't much of a change at all. Then I tried "RCA" and that gave interesting results going in the right direction for once. Applying an ICC profile with those primaries (vaguely copied from a bad quality diagram, mind you) gave me this image change:


White point I always kept at D65, actually because I don't much understand how white point works in this sense yet, so I didn't wanna mess with it.

I've attached the zipped ICC profile I created. You can just open a screenshot in PS and do an "Assign colorspace" with it and it should give you this kind of change. It might not be 100% precise as a method (since screenshots might be sRGB converted from Rec709) but whatever.

Anyway, this goes further in making me think it's something to do with these CRT's just not being calibrated or maybe the people using them to grade footage just blindly trusted the spec sheet of the displays but they actually had different primaries.

If anyone has both a suited CRT and a display calibrator (colormunki or similar), you can use that to create an ICC profile for a display using the software displaycal (free!). That can then either be directly applied to images to make them look as if they were graded on that display, or the primaries (red,green,blue) can be extracted from it and an idealized profile can be created which might be a more generally-useful thing.

[zoidberg]

Apologies if this has already been mentioned within the thread but there is a twitter account called @CRTpixels which does a lot of comparisons between pixel art as displayed on software emulators vs the CRT displays of the time. It's worth a look, some of the differences in perceived quality and also shifts in colour are quite striking