The History of 240p 

1:17 FUN FACT: The flicker that you see in older projectors are the reason why movies are sometimes referred to as "Flicks".

2:15 Have you ever tried to stick a fork in a power outlet? It hertz a lot, like 60 times per seconds !

Short Answer: 240p is a resolution my Wifi defaults to when watching RU-vid videos.

"what is 240p?" For me it's probably the resolution I'm gonna have to watch this video at, because I'm redownloading Black Mesa for the public Xen beta while I watch this.

The “P” stands for Progressive Scan.

In all my years of researching technical film history, I have never heard of that reasoning for how we got to 24 fps. It does sound like things got muddled a bit and then a misunderstanding got it backwards. Early silents varied wildly in framerates as hand cranking was up to the feel of the cinematographer and the projection was equally variable until things got standardized. Usually silents were at 16-18 fps. Some were really extravagant and went up to the 24 fps we know today. As far as I have understood it, the 16-18fps range was considered good enough and we wouldn't have seen a change if it wasn't for sound. When sound entered the movie world there were some experimentations where you had a separate playback device that was manually synched in the theatre. But it was deemed much, much more feasable to add the sound to the film itself. So the quality of the sound now was determined by the speed of the film it was recorded to. 24 fps was simply the lowest possible speed that made an acceptable and intelligible sound. the only real reason they never went faster than 24 fps was money. 24 was good enough and it became the accepted standard. The multiflashing was purely to reduce apparent flickering for viewers. In a movie theatre with film projection. Half the time spent watching the image, the audience is actually staring at a black screen. Cheap projectors both back then and even later on did a single flash. The earliest projectors were multitool devices that could be used both as the camera and the projector and used the same mechanics and single flash shutter. The Butterfly shutter (as is shown in this video) provides a double flash of each image and there are/were even triple flash shutters available for extra flicker-reduced image. You could technically add more holes, but you need enough black at one point during the revolution of the shutter so that the film can move when we don't see it. And if you jerk the film too fast during too short a timeframe you are in danger of ripping the film apart. So 2-3 flashes per frame were, again, deemed good enough for general consumption.

When you said 'this footage was shot at 1000 frames per second' I still thought you were referring to the original footage and for a moment I was left wondering why such an advanced camera would produce such a terrible image haha.

What a great video. I was surprised about the source of scan lines. I just thought they were present on all CRT tv images, but I am dumb. Also it now makes sense why game consoles use the non interlaced video format, they saved money using low resolution and not needing to process and output interlaced video and they got 60 Hz as a bonus. Thanks for clearing up the mystery of 240p.

1:39 Originally, silent films were shot at approximately 16 frames per second (it varied somewhat), and each image was flashed three times for a 48hz refresh rate. Though theaters would often project it faster to squeeze in one extra showing for the day. When sound came to film, it was recorded as a linear track besides the picture. To get decent sound quality, the framerate was increased and standardized to 24fps.

240p is what I’m watching on

Wow! You are an extremely underrated channel! You deserve so many more subscribers. By the way, very helpful video, thank you.

I LIVE for this knowledge!!! Your videos are perfect! I cannot get enough!

One thing that bothers me is when I see an arcade emulator that applies the scanline effect going left to right across a portrait orientation picture. The scan lines are always across the long way regardless how the CRT is oriented.

Can I just say I love your ability to keep these history of videos nice and brief very few have the ability to do that well. although it does make me wish every time I see the end of a video and you put all the other terms that you would do a series kind of explaining them all in one go and how they relate to each other. I know technology connections does something similar to that but I think you do a really good job of explaining this stuff and they make for great videos to send to my friends who ask me about this stuff.

Couple of mistakes in this video. Each field in an interlaced video is a separate image captured at a separate points in time. Two fields never combine into a single image. The phosphor afterglow lasts far too short for that and has no impact in reducing flicker, that's up to your eyes and brains persistence of vision (flicker fusion). So TV run at we would call today 60fps all the time, just with each other line missing, alternating which one each field. The reason why video games go for 240p instead of 480i is not to gain 60fps, which they could already do, but to reduce line flicker. If a digital image is shown at 480i the pixels keep jumping up and down with each new field, that creates noticeable flicker artifacts. By going 240p they get a more stable image and since the devices aren't capable of rendering higher resolution, nothing is lost. The reason why line flicker isn't an issue for normal TV shows is that the cameras scan the lines in overlapping pattern, so line 1 contains information from line 2 as well, early computer weren't able of this kind of blending.

Literally just came over here from Bob at RetroRGB's recommendation before watching the recent 480i deep dive he did. This short 240p video is simply phenomenal. It clarified and taught me so much in just 7mins!!! An absolute must for all us beginner geeks. Thank you 🙏

you forgot to add that the first video ever on youtube was 240p

You give the important information in an uncomplicated manner and very quickly. Very well done

Man, thats a lot of good information here. Thanks for this. I Will recommend your Channel for my friends. Keep the good work

Fascinating! After watching your video about dithering on the Genesis, your other about SNES aspect ratio, before this, I knew this was a channel to subscribe to! Now, I have a lot of missed content to go over as well!

This is such a great channel! Thank you for all the very good explanations :)

What a great video, very informative and a fascinating subject. Thanks!

2:49 >high definition *240*

This video was so great-it was well researched and really informative! In your update video, you said to mention if there may be videos that you’d like to see more of, and I’d love to see more videos along these lines.

Pretty good little channel you l’ve got here. Deserves 10x more subscribers, easily.

Awesome, been trying to wrap my head around this what with the Super NT coming out recently. Thanks!

I wish YT had suggested you sooner. What a lot of great content. Thank you.

This channel is so underrated! You explain things very well.

On the PC side of things, the monitors to go with CGA and EGA were designed to show 200-line modes with 200 lines. When IBM made VGA, they upped the horizontal refresh rate to allow higher resolutions and made the graphics system output each line of pixels twice in the 200-line modes, so 320*200 and 640*400 are indistinguishable to a VGA monitor.

I'm going to call it double strike from now on. Great video btw!

This channel really turned to be my fref this days. Love it !

Thanks, DG. It's really good to know the history behind all this! xDD

Loved this! Subscribed!

this background music was dang good! Thank you!

This was very helpful in explaining the differences. Thanks!

Freaking fantastic & informative video man, thanks!

Great video. Especially about the scanlines

Very informative!! Great video!

Very informative. Well done.

Only you can take a boring subject and make it actually interesting. Loving this channel a lot.

1:06 I like how the animation you made to explain how films use the Phi phenomenom is also an example of the Phi phenomenon.

This video should have been twice as long. There is so much more to detail!

Very informative and easy to grasp you rock

Thank you so much for the informative video.

Great vid as always

While watching this, video has changed its resolution from 1080p to 240p. Creepy.

Amazing video!!!!

I watched this video in 144p Some people didnt understand my comment lol

Great video I learned something new today

Amazing video, thanks!

Deep inside we all know that now a days 240p is when you have to save data on your phone while vacation.

480 scanlines were chosen for computers and video game consoles that came later as a de-facto resolution simply because it was the largest number divisible by 8 that could fit in a 483-line display. a width of 640 'dots' or pixels ensures that the aspect ratio is a constant 4:3 and can properly fit the display.

Great video - thank you!

Excellent video!

I thought this channel has at least 500K subs or higher. Good content, hope your channel grow more soon

I love scanlines on old games. It just looks cool!

Just discovered your channel and it is awesome!

Amazing video.

That was a positively excellent synopsis in under 7 minutes. Kept it at a good level, add nothing flashy, just pure pertinent information. Subscribed. Please do more of these.

Huh, pretty interesting. I actually learned a lot today. Thanks!

This is a very good explanation of the difference between frames and fields, something people get wrong constantly.

Me: *watches video in 480p* My phone: *drops video quality to 240p*

Well explained!!

Adding on, digital displays tend to handle such a signal in one of two ways: 1.) Completely ignore the timing change and interlace it anyway 2.) Apply a line-doubler to make a more literal 240p picture

God damn, just as it was getting interesting it ends, you got more? Great vid BTW

I know where that music's from... *I see you're a man of culture as well.*

Fun fact: the letter at the end of the resolution indicates the drawing method. So: 480i is interlaced and 480p is progressive, same for the other resolutions. 1080i interlaced, 720p progressive, 2160p progressive, 144i interlaced, etc

incredible research!

This channel is incredible

240p is _pure disappointment_ when you see a hot thumbnail on PH and then it turns out that it is the maximum resolution😩

The music was awesome!

Interesting video, thank you.

Also, in film, the motion that occurs in each still image is captured as a blur. Each frame contains captured motion. In a game it does not.

Watch in 240p for the ultimate experience

I had a flat CRT when I was younger but apparently it didn't show any scan line effect on a famiclone. Did the 2006s CRTs had upscaling in them already? Or unofficial famicoms had better specifications and just run at 240p if the TV also supported it?

This channel is pure old school engineering !

Cool video

Interesting... I never knew that those old consoles were completely skipping half the scanlines, or that it was even possible to tell the TV to re-use the same field. I had always just assumed the TV automatically switched fields and the consoles were simply drawing their next frame on different fields like normal video. I figured that phosphor fading was masking the combing. I also always thought the scanline effect was always visible regardless of the video source, but then again... I did play a LOT of games as a kid.

This clears up the 60 progressive of the game on a 60 interlaced TV issue I never really understood.

I do hope your videos are open for community to add subtitles. I must translate it for that kind if info is a must for any retrogamer.

I recall no body talking about 240p before youtube. First one I recall was 720p when people had flats after crt's, it was called HD and Full HD for 1080p (or HD ready) I used to work as tv repair, peeps were just talking about crt size (which was measured differently than flat ones) but also the refresh rate was more commonly asked wheter it was over 60Hz and tubes that were flat (Sony trinitron tubes). There is more to it but yeh, nobody talked about resolutions much before flats were out.

Watching this in 240p for the true experience

Arcades mostly used it too and they could ignore tv standards and make the monitors however they wanted (some did). At 4:53 when you say they needed to save money, I assume this is on memory? Rom to store the graphics and/or ram to draw to screen?

This video made me subscribe.

I've always hated scanlines so when I made some emu consoles for my brothers years back I didn't put them on. Years later, my brother gets an SNES mini and tells me that he loves it because of "these things called scanlines". I laughed and told him that he could have used them years ago on what I gave him, but it didn't even occur to me that anybody else would like them either. Crazy how different people can be, even down to these little things.

I'm confused. I use a CRT TV for my ZX Spectrum, and the black lines I see are vertical... Why is it? Or I just don't look at it right?

So is the story exatly the same when it comes to 288p in PAL? does most games of 8-bit/16-bit/32-bit era run in 288p 25fps (50Hz) in PAL regions?

It was very clever. As long as the tv has 60 pictures or fields a second its fine. But my question is what happens when the CRT has to update an odd field and there is none? Does it just see that as a horizantal blanking refrence and ignore it?

I'm old. To me it seems sacrilege to refer to an authentic analog signal as 240p or 480i. The 240p or 480i refers to common digital representations of those signals and you didn't really start hearing those terms until this century.

Which books do you recommend for this subject? Thanks!

watching this in 240p to set the mood

On PAL you have 576 scanlines. Some consoles used the extra ones, others just added black bars. So we also had 256p and such.

3:22 when people say crts have no native resolution thats not true right? the vertical resolution is always max 483, correct? the horizontal resolution can be anything?

Upvoted as soon as I saw the Atari 800 :)

Keep the vids coming and I’ll watch!

I watch these things to decipher my childhood and i am forever stuck in the past

Great vídeo . Degrats

I saw this in my recommenced tab for some reason.

Amazing explanation, I've absorbed 25% of it but still learned heaps

Back in the 386DX2 66MHZ days, popular video cards such as Cirrus Logic, Trident, S3, ATI, etc were only able to produce CGA 4 color, EGA 16 color, and VGA 256 color up to a maximum of 320x200. There was 3rd party MSDOS programs such as UNIVBE which made it possible to display SVGA screen modes up to 320x240 to 1024x768 but it never performed that fast on anything slower than a Pentium. Warcraft II and Terminal Velocity were two of the first games that made use of SVGA display modes in their games. Graphics cards couldnt catch up. and with the release of 3DFX voodoo and OpenGL and Microsoft creating DirectX, things started getting very competitive.