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PostPosted: Thu Feb 04, 2016 9:28 pm 
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It seems like trying to fit a perfect 255,0,0 red, or 255,255,0 yellow into a smooth color ramp, is well, a lot harder than it looks. Is it possible to make a ramp that does not look uneven?


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PostPosted: Thu Feb 04, 2016 10:04 pm 
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Maybe try to use an exponential curve between them instead of a linear blend? e.g. gamma correct blending


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PostPosted: Thu Feb 04, 2016 10:29 pm 
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psycopathicteen wrote:
It seems like trying to fit a perfect 255,0,0 red, or 255,255,0 yellow into a smooth color ramp, is well, a lot harder than it looks. Is it possible to make a ramp that does not look uneven?


Sure they can! Primary colors can be used as a nice ramp between separate color ranges.
At least, that's what I've used them for.

(...I can't seem to find the palette I had figured out, from 2 years ago. :|)

If you're serious about figuring things out, try for all 4 primaries: red, blue, green, yellow.


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PostPosted: Fri Feb 05, 2016 4:59 pm 
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Alp wrote:
...all 4 primaries: red, blue, green, yellow.
:|
Assuming these are primaries, how could these be all of them?

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PostPosted: Fri Feb 05, 2016 6:10 pm 
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ccovell wrote:
Alp wrote:
...all 4 primaries: red, blue, green, yellow.
:|
Assuming these are primaries, how could these be all of them?


For the sake of this thread I'm including magenta and cyan as primary colors too, since they're at the corners of the color cube.

BTW, I'm not sure if people know what I'm talking about. I'm not talking about making a color ramp between primary colors. I'm talking about shadow/highlight gradients of a primary color. It tends to look better if the middle shade is slightly darker or lighter than the fully saturated color. From my experience, secondary colors like orange and blue-violet are easier to fully saturate without looking weird in a shadow/highlight ramp.


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PostPosted: Sun Feb 28, 2016 12:22 am 
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I just remembered something. My LCD screen looks different depending on the angle, so that could be the reason why pure primary colors tend to pop out too much. If I make them look good at one angle, they would look disjointed at other viewing angles.


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PostPosted: Sun Feb 28, 2016 12:31 pm 
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This is a weird thing to say, but because you brought up LCD TVs, I'm going to say that I forgot how good a good CRT TV looks with these old games. I have a crappy Emerson LCD TV in my room and a nice Phillips flat screen CRT TV that I brought out for a party, and the old TV beats the crap out of the newer one. It was much more vibrant and didn't distort at different angles, looked less blurry, had no lag, and had much better sound (like I said, it's a higher quality TV even if older). I don't know why I felt like sharing that, but I don't think this thread is really going anywhere anyway. I just always hate people saying that you should hook up old technology to newer TVs and stuff. The way I see it, you use SD technology on SD TVs, and HD technology on HD TVs. One thing I never really thought of is that I imagine 720p video would look cleaner on a 720p TV than 1080p or something like that. Another thing I also wondered is did somebody say that even if an HD TV is receiving HD signal, it will still lag?


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PostPosted: Sun Feb 28, 2016 12:38 pm 
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An HDTV receiving a 1080i signal, such as broadcast or cable TV, is likely to lag to deinterlace it. It may lag even when receiving a progressive signal in order to run various enhancement filters on the image, but better TVs have a "game mode" option to turn enhancement down to minimum.

Among LCDs, IPS is more consistent than TN at different viewing angles. This is why smartphones and tablet computers are more likely to use IPS, as a portrait-oriented tablet will have the user's two eyes at significantly different viewing angles.

The problem with using old TVs with old consoles is twofold. For one thing, old TVs are less likely to fit in a cramped apartment. For another, old TVs wear out. My 27" Magnavox died, and now I'm back on a 13" Panasonic.


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PostPosted: Sun Feb 28, 2016 12:53 pm 
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tepples wrote:
For another, old TVs wear out. My 27" Magnavox died, and now I'm back on a 13" Panasonic.

After declaring my HDTV completely unsuitable for retro consoles, I decided to keep my 21" Samsung, which thankfully still works. Since then, I also salvaged a 14" CCE (which's a traditionally crappy brazilian brand), just in case.


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PostPosted: Sun Feb 28, 2016 1:15 pm 
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Espozo wrote:
This is a weird thing to say, but because you brought up LCD TVs, I'm going to say that I forgot how good a good CRT TV looks with these old games. I have a crappy Emerson LCD TV in my room and a nice Phillips flat screen CRT TV that I brought out for a party, and the old TV beats the crap out of the newer one. It was much more vibrant and didn't distort at different angles, looked less blurry, had no lag, and had much better sound (like I said, it's a higher quality TV even if older). I don't know why I felt like sharing that, but I don't think this thread is really going anywhere anyway. I just always hate people saying that you should hook up old technology to newer TVs and stuff. The way I see it, you use SD technology on SD TVs, and HD technology on HD TVs. One thing I never really thought of is that I imagine 720p video would look cleaner on a 720p TV than 1080p or something like that. Another thing I also wondered is did somebody say that even if an HD TV is receiving HD signal, it will still lag?


There's a million things wrong with new TV sets.

-cutting the frame rate of analog channels to 30fps
-sampling an analog signal at a low horizontal resolution, and scaling it up
-forcing everything to widescreen by default
-up scaling the picture in a certain way that adds excessive blurring
-a bunch of unnecessary image filtering that smears anything that moves


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PostPosted: Sun Feb 28, 2016 2:06 pm 
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tepples wrote:
For another, old TVs wear out. My 27" Magnavox died, and now I'm back on a 13" Panasonic.

This is the biggest problem in my opinion. Fixing a nearly (or over!) three decades old console with dead discrete components is easy, and the custom ones are unlikely to die (probably will outlast us, even). Good luck managing to fix an old CRT TV though, especially since the things most prone to fail are those involved with the tube.

Now, really most of the shit that gets in the way in modern TVs could be fixed because it's mostly a limitation of their programming. But that's not gonna happen as long as there isn't a good business reason for that. Maybe if in the future somebody decides to release a niche "retro TV" designed specifically to cope with those old quirky analog signals.


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PostPosted: Sun Feb 28, 2016 2:13 pm 
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Sik wrote:
But that's not gonna happen as long as there isn't a good business reason for that.

And as time goes by, there will be less and less reasons to do it, because the number of analog video devices still in use is quickly approaching 0. I don't have any faith in TV manufactures ever improving analog video support. Quite the opposite really, I expect them to completely get rid of analog inputs soon. Our best bet will likely be standalone converters created by hardware people that are part of the retro scene.


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PostPosted: Sun Feb 28, 2016 2:40 pm 
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We could build a laser SDTV without too much difficulty. Modulating red and blue solid-state laser diodes at the required ≈3MHz bandwidth is pretty easy; I'm not certain whether the nonlinear optics used by green solid-state lasers pose a problem or not.

The horizontal deflection is the only particularly hard part, and I think a high-precision many-sided front-surface mirrored polygonal prism should be workable there.


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PostPosted: Sun Feb 28, 2016 2:43 pm 
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I totally understand everything you just said. :mrgreen:


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PostPosted: Sun Feb 28, 2016 3:23 pm 
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tokumaru wrote:
I totally understand everything you just said. :mrgreen:
lidnariq wrote:
Modulating
= "drive"
Quote:
nonlinear optics used by green solid-state lasers
Weirds__t. wikipedia:Second-harmonic generation. Green solid-state lasers are actually a 1056nm infrared laser diode that is magically converted into 528nm green light.

I have no idea how it works, so I have no idea if there's a bandwidth consideration.
Quote:
The horizontal deflection is the only particularly hard part
SDTV Horizontal deflection frequency is ≈16kHz, or 960000 per minute. A flat surface with both sides mirrored would have to spin at 480000 RPM, well above what's feasible in air.
Quote:
many-sided mirrored polygonal prism
A 64-gon prism (i.e. a 66-sided solid, with 64 separate rectangles and top and bottom are 64-gons) would only have to spin at 15000 RPM
Quote:
front-surface
wikipedia:First_surface_mirror


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