Normally it should open e.g. for SNES a 256*224 screen and would be 50-50 black-bright on full white color with that TVL, 1000 or so. Probably less bright colors should be like 25-75, or 40-60.
An interesting idea would be to design a shader, that reads color luminance (take in to account the actual light emmited by colors - that is 30% red, 60% green, 10%blue, the reason why yellow is so bright and magenta is not), then apply black scanlines based on that, 50-50 on luminance 0.8-1.0, let’s say on 1440p integer 3-3, 2-4 on luminance 0.4-0.8 and 1-5 on luminance 0.0-0.4. You would need at least 1440, for 1080p with 4 pixel scaling would be nonsense. But then you would need an ultra bright monitor.
Yellow (full red and green) and magenta (full red and blue) drawn then grayscaled. Would not be possible to emit the same light and affect a scanline the same.
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Yeah I’m not sure screenshots like this really get across what you see in person - sure at a basic level it shows how lit up the phosphors are but it doesn’t get across how much light they are emitting as in the camera/display will be clipping the luminance (partly because they’re SDR)
I think this photo was taken with HDR camera. Even my cellphone that I am writing now has an HDR camera. But for sure I bet is very bright in person.
Possibly but there are variations in HDR and at some point it is being clipped as I can guarantee that isn’t what it is like in person.
That picture and caption together 
I haven’t either, but they should look exactly like a trinitron PC monitor, which is what they are, just with the ability to sync 15 kHz signals.
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Is that a photo taken of your own CRT monitor? If so what model is that?
No, that’s a BVM, not mine.
Just as an example zooming in on this image you can clearly see clipping occuring in the whites
Also the rest of the image will undoubtedly be getting tonemapped down (darkened) - in part because some of the image is blowing out of the top end of the camera/file format/displays luminance range. It’ll probably be doing this (tonemapped down) anyway as it’ll be bright.
Going back to the Yoshi Island screenshot - the whites in it are quite a bit darker than the whites on my phone i.e the white web page surrounding the image. So I guess it’s either the camera or file format crunching the luminance levels and not my phone’s display.
Also the Yoshi Island screenshot is clipped to heck because you can see it’s got no detail - youd see the pixel grid with your naked eye at that distance.
Yes so this is an interesting point - I’d imagine there is a difference in the size of the screen though? Because of that I’d assume the scan lines would be further apart and so more dark between them giving a darker overall image and this I guess the Sony engineers would have adjusted the scanline brightness to make up for that difference? I don’t know - has anybody taken the peak luminance at the center of the scanline phosphor on a 32/24inch BVM compared to the same point on 15inch Trinitron PC monitor?
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There are smaller BVMs and larger PC monitors, but yeah, the very big ones have them very far apart.
I only have an xm29+ for reference, but the 240p scanlines on it are very far apart, indeed, and the brightness is roughly similar between a 240p image and a 480p+ image, despite the 480p image having much less visible black.
@DariusG the problem with doing that is you end up with screwy black levels. GritsScanline is a shader that does something similar and it makes the image look lifeless and blown out at the same time, as darker things get pushed even darker by the surrounding black, while brighter things keep their proper color.
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So when you say brightness is roughly similar are you talking about overall image brightness or individual peak scanline brightness?
Admittedly this will be difficult to tell with your naked eye as it’s also adjusting exposure by widening and narrowing your iris - you’d need proper tools to do it such as a spectroradiometer and colorimeter.
Yes I checked it and indeed it takes in to account that blue is less bright and green is more bright, but I don’t see it is lifeless, it looks fine on my screen. Scanlines are consumer CRT style though.
overall brightness, which suggests an individual scanline would need to be pretty damned bright. You can see my pics of it here: http://filthypants.blogspot.com/2015/08/nec-xm29-plus-broadcast-monitor.html, though the 480p shot is much more clipped than the 240p/480i shots, so dunno.
Great blog post - you can really see the range of luminance your monitor is pumping out at the scanline level in this image:
Look at the clipping (caused by the camera not your monitor) that’s occuring in those blue letters compared to the detail you’re seeing in the darks - you can actually see the coloured phosphors in them and shows the kind of luminance range there is.
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Just as a real world example of what we’re dealing with when taking photos of emissive surfaces: the street light in this image with the naked eye is very orange (it’s heating up) and you can see all the detail in it. In the photo on the other hand the scene looks COMPLETELY different:
There’s a massive orange bloom in it that doesn’t exist with the naked eye and dark wall on the right has been lightened up considerably. There’s tons of stuff different.
(This is taken with ‘HDR’ enabled on my phone’s camera too).
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That is a very good example.
One issue is the use of Cell Phone cameras.
They make far too many decisions for you. Even software analog controls like ISO, Shutter Speed, and manual White Balance only yield so much.
HDR on a phone is a little misleading also. It takes multiple exposures, at different resolutions, and combines them into one image. It gives you a lot of mathematical information, valuable in a good RAW image editor, but I’m not sure it gives you any better photo than good white balancing.
Your point is well taken though… we can’t trust photos of objects that emit light.
(I miss the ability to pick the right film for my medium.)
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It’s true that photos over-expose light, and they are not so trustworthy to see how a BVM looks like in reality. Could only do so if you have one and make a shader side by side with such a monitor. And then again an LCD is not up to the task. So we can only mimic up to a point.